Fluid detection device and control method, electronic device

Abstract

The embodiment of the application provides a kind of fluid detection device and control method, electronic equipment, it is related to fluid measurement technical field, for reducing the fluctuation of the performance of fluid detection device with environmental temperature variation.The fluid detection device includes voltage source, at least one heating element, at least one thermistor and controller.The thermistor generates the first signal corresponding to the temperature of the thermistor.When the environmental temperature where the thermistor is located is the first environmental temperature, the voltage source at least outputs the first voltage to the thermistor, and when the environmental temperature where the thermistor is located changes from the first environmental temperature to the second environmental temperature, the voltage source at least outputs the second voltage to the thermistor, so that the microphone module can still maintain higher performance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fluid measurement, and particularly relates to a fluid detection device and a control method and an electronic device. BACKGROUND

[0002] An acoustic vector sensor (AVS) has the characteristics of good frequency and spatial consistency in sound signal collection, strong noise suppression capability, and good long-distance sound pickup effect, and is widely applied to sound pickup technology of intelligent terminals.

[0003] Sensitivity is an important technical index for measuring the above-mentioned microphone, such as the acoustic vector sensor. At present, the sensitivity of the acoustic vector sensor is usually calibrated before the acoustic vector sensor is shipped. However, as a sound wave receiving device, the performance (such as sensitivity) of the acoustic vector sensor is affected by the external environment (such as temperature) when the user uses the acoustic vector sensor in different environments, thereby generating a large fluctuation. In this way, the user cannot guarantee that the acoustic vector sensor works in the best performance state when using the acoustic vector sensor, thereby reducing the user experience. SUMMARY

[0004] Embodiments of the present application provide a fluid detection device and a control method and an electronic device, which are used to reduce the fluctuation of the performance of the fluid detection device such as the acoustic vector sensor with the change of the environmental temperature.

[0005] To achieve the above object, the present application adopts the following technical solutions:

[0006] In one aspect, an embodiment of the present application provides a fluid detection device. The fluid detection device includes a voltage source, a channel for fluid flow, at least one heating element, at least one thermistor, and a controller. The heating element is electrically connected to the voltage source. The thermistor is electrically connected to the voltage source. When fluid flows through the channel, the fluid flows through the thermistor to facilitate the thermistor detecting the flow (e.g., flow rate) of the fluid such as gas. The thermistor is configured to sense the ambient temperature of the thermistor, which is related to the temperature of the thermistor itself. When the ambient temperature of the thermistor is a first ambient temperature, the voltage source outputs at least a first voltage to the thermistor. When the ambient temperature of the thermistor is a second ambient temperature, the voltage source outputs at least a second voltage to the thermistor. The first ambient temperature and the second ambient temperature are different, and the first voltage and the second voltage are different. In this case, when the fluid detection device is in the first ambient temperature, the fluid detection device has high sensitivity and good signal-to-noise ratio by applying the first voltage to the thermistor. When the use environment of the fluid detection device changes, for example, the temperature changes from the first ambient temperature to the second ambient temperature, the fluid detection device can still maintain high sensitivity and good signal-to-noise ratio by applying the second voltage to the thermistor.

[0007] In one embodiment, the first ambient temperature is higher than the second ambient temperature. The first voltage is greater than the second voltage. In this way, when the ambient temperature decreases from the first ambient temperature to the second ambient temperature, the voltage applied to the thermistor at least decreases from the first voltage to the second voltage. Alternatively, when the ambient temperature increases from the second ambient temperature to the first ambient temperature, the voltage applied to the thermistor at least increases from the second voltage to the first voltage. In this way, by adjusting the voltage applied to the thermistor, the fluctuation of the performance of the fluid detection device caused by the ambient temperature is reduced.

[0008] In one embodiment, the fluid detection device further includes a controller. The controller is electrically connected to the voltage source. The thermistor is configured to generate a first signal corresponding to the temperature of the thermistor. The controller is configured to output a voltage control signal to the voltage source according to the first signal to control the voltage output by the voltage source. When the ambient temperature of the thermistor is the first ambient temperature, the controller controls the voltage source to output the first voltage. When the ambient temperature of the thermistor is the second ambient temperature, the controller controls the voltage source to output the second voltage. The controller can be part of an application processor in an electronic device having the fluid detection device, or can be a separate digital signal processor.

[0009] In one embodiment, the controller comprises a processor circuit and at least one control component. The processor circuit is configured to output a voltage control instruction according to the first signal. The control component can comprise a voltage control circuit. The voltage control circuit is electrically connected with the voltage source and the processor circuit. The voltage control circuit is configured to output a voltage control signal to the voltage source according to the voltage control instruction, so as to control the voltage output by the voltage source. In this way, the processor circuit can obtain the resistance of the thermistor according to the first signal, and output the voltage control instruction to the voltage control circuit according to the resistance, so that the voltage control circuit can control the voltage output by the voltage source.

[0010] In one embodiment, the control component further comprises a current acquisition circuit. The current acquisition circuit is electrically connected with the voltage source and the processor circuit. The current acquisition circuit is configured to acquire the current flowing through the thermistor and output to the processor circuit. In this way, the processor circuit can acquire the resistance of the thermistor according to the current I output by the voltage source to the thermistor and the voltage U output by the voltage source through the current acquisition circuit. Then, the ambient temperature is calculated according to the resistance, and the voltage control circuit is used to control the voltage source to provide a voltage to the thermistor that matches the ambient temperature, so as to reduce the fluctuation of the performance of the fluid detection device caused by the influence of the ambient temperature.

[0011] In one embodiment, before obtaining the first signal, the processor circuit is further configured to receive a first mode selection operation of a user, and output a voltage control instruction to the voltage control circuit in response to the first mode selection operation, so that the voltage source outputs a first mode initial voltage. Alternatively, before obtaining the first signal, the processor circuit is further configured to receive a second mode selection operation of a user, and output a voltage control instruction to the voltage control circuit in response to the second mode selection operation, so that the voltage source outputs a second mode initial voltage. The first mode initial voltage is smaller than the second mode initial voltage. The working mode of the fluid detection device can include a first mode, such as a power saving mode, and a second mode, such as a high performance mode. In the power saving mode, the fluid detection device has a small power consumption, but the electrical signal output by the fluid detection device is small, and the performance (e.g., sensitivity) of the fluid detection device is poor. Conversely, in the high performance mode, the fluid detection device has a large power consumption, but the electrical signal output by the fluid detection device is large, and the performance of the fluid detection device is good. In this case, the processor circuit can control the voltage source to provide different voltages to the thermistor according to the mode selection operation of the user to meet the requirements of different modes.

[0012] In one embodiment, the first mode initial voltage is 2V-4V. When the first mode initial voltage U1 is less than 2V, the voltage applied to the thermistor is too small, so that the sensitivity of the fluid detection device is too low, which affects the performance of the fluid detection device. In addition, when the first mode initial voltage U1 is greater than 4V, the voltage applied to the thermistor is too large, which increases the power consumption of the fluid detection device and reduces the power saving effect. In some embodiments of the present application, the first mode initial voltage U1 described above can be 2V, 2.5V, 3V, 3.5V or 4V. In addition, the second mode initial voltage is 5V-12V. When the second mode initial voltage U2 is less than 5V, the voltage applied to the thermistor is too small, so that the sensitivity of the fluid detection device is too low, which is not conducive to the fluid detection device to reach the standard of high performance. In addition, when the second mode initial voltage U2 is greater than 12V, the voltage applied to the thermistor is too large, which increases the power consumption of the fluid detection device, the thermistor generates a lot of heat, and increases the risk of thermistor failure. In some embodiments of the present application, the second mode initial voltage U2 described above can be 5V, 6V, 7V, 8V, 9V, 10V, 11V or 12V.

[0013] In one embodiment, the at least one thermistor includes a first thermistor and a second thermistor. The first thermistor and the second thermistor are respectively used as two branches of the bridge circuit. When the resistance values of the first thermistor and the second thermistor change with temperature, the voltage difference △u0 output by the bridge circuit will change. In this way, the resistance value change of the first thermistor and the second thermistor can be converted into the voltage difference △u0. Thus, by obtaining the voltage difference △u0, the sound information can be obtained.

[0014] In one embodiment, the fluid detection device further comprises a first resistor, a second resistor, and an operational amplifier. The first resistor is connected in series with the first thermistor between a voltage source and a ground terminal; the second resistor is connected in series with the second thermistor between the voltage source and the ground terminal. For example, the first resistor is electrically connected between the first thermistor and the ground terminal. The second resistor is electrically connected between the second thermistor and the ground terminal. A first input terminal of the operational amplifier is electrically connected between the first resistor and the first thermistor, and a second input terminal of the operational amplifier is electrically connected between the second resistor and the second thermistor. In this case, the first thermistor, the second thermistor, the first resistor, and the second resistor can form a bridge circuit. The resistance values of the first resistor and the second resistor are constant and fixed. When the resistance values of the first thermistor and the second thermistor change with temperature, the voltage difference Δu0 output by the bridge circuit will also change. Thus, the change in the resistance values of the first thermistor and the second thermistor is converted into the voltage difference Δu0. Thus, by obtaining the voltage difference Δu0, the sound information can be obtained. In addition, the operational amplifier is used to amplify the voltage difference Δu0, so that the signal obtained by the fluid detection device, such as a microphone module, is easier to identify.

[0015] In one embodiment, the fluid detection device further comprises a switch and a comparator. A first input terminal of the comparator is electrically connected to one end of the first thermistor or the second thermistor away from the voltage source, a second input terminal of the comparator is used to receive a reference voltage, and an output terminal of the comparator outputs a control signal. The switch is connected in series with the heating element, a gate terminal of the switch receives the control signal, and the switch selectively conducts based on the control signal. The comparator is used to control the switch to be turned off if the voltage at the first input terminal of the comparator is greater than the reference voltage, so as to avoid the temperature of the environment or the thermistor being too high (or the temperature being higher than a first warning temperature). At this time, the heating element is in a disconnected state with the ground terminal, and no current flows through the heating element, so that the heating element no longer provides a temperature field to the first thermistor and the second thermistor, thereby achieving the purpose of reducing the temperature of the first thermistor and the second thermistor. Alternatively, if the comparator compares that the voltage at the first input terminal of the comparator is less than the reference voltage, the switch is controlled to be turned on. At this time, the heating element is in an electrically connected state with the ground terminal, and current flows through the heating element, so that the heating element provides a temperature field to the first thermistor and the second thermistor, thereby avoiding the temperature of the environment or the thermistor being too low (or the temperature being lower than a second warning temperature), so as to improve the sensitivity of the fluid detection device.

[0016] In one embodiment, the fluid detection device further comprises at least one noise reduction circuit mode converter and a digital signal processor. The noise reduction circuit is electrically connected between the first thermistor and the first input terminal of the operational amplifier, and is also electrically connected between the second thermistor and the second input terminal of the operational amplifier. The noise reduction circuit is configured to perform noise reduction processing on the voltage difference △u0 output by the bridge circuit in which the first thermistor and the second thermistor are located. The input terminal of the analog-to-digital converter is electrically connected to the output terminal of the operational amplifier, and is configured to convert the analog signal output by the operational amplifier into a digital signal. The input terminal of the digital signal processor is electrically connected to the output terminal of the analog-to-digital converter, and is configured to perform at least one of noise reduction processing, reverberation elimination processing, or echo elimination processing on the digital signal output by the analog-to-digital converter.

[0017] In one embodiment, the at least one thermistor comprises a first thermistor and a second thermistor. The first thermistor and the second thermistor are respectively configured as two branches of the bridge circuit. The voltage source comprises three sub-voltage sources, namely a first sub-voltage source, a second sub-voltage source, and a third sub-voltage source. The first thermistor is electrically connected to the first sub-voltage source, the second thermistor is electrically connected to the second sub-voltage source, and the heating element is electrically connected to the third sub-voltage source. In addition, the controller comprises three control components, namely a first control component, a second control component, and a third control component. The first control component is electrically connected to the first sub-voltage source. The second control component is electrically connected to the second sub-voltage source. The third control component is electrically connected to the third sub-voltage source. In this way, compared with the scheme in which different thermistors and a heating element are connected to the same voltage source, the scheme in which the same thermistors and a heating element are powered by different voltage sources, and the different voltage sources are respectively electrically connected to different control components, can reduce the power consumption of each voltage source.

[0018] In one embodiment, the fluid detection device further comprises a temperature detector. The temperature detector is electrically connected to the controller, and is configured to collect the temperature of the thermistor and transmit the collection result to the controller. In this way, the controller can determine whether the resistance of the thermistor calculated by the processor is accurate by determining whether the temperature of the thermistor collected by the temperature detector is within the working temperature range. Next, the ambient temperature in which the thermistor is located is obtained based on the resistance of the thermistor, and a voltage matching the ambient temperature is obtained. Alternatively, the controller can directly obtain the ambient temperature in which the thermistor is located based on the temperature of the thermistor collected by the temperature detector without calculating the resistance of the thermistor, and obtain a voltage matching the ambient temperature.

[0019] In one embodiment, the first signal is used to represent the resistance of the thermistor. When the thermistor is a thermistor wire, the resistance value of the thermistor wire can be used as the first signal. The first signal can be an analog signal or a digital signal.

[0020] In one embodiment, when the ambient temperature of the thermistor is a third ambient temperature, the voltage source outputs a third voltage to the heating element; when the ambient temperature of the thermistor is a fourth ambient temperature, the voltage source outputs a fourth voltage to the heating element. The third and fourth ambient temperatures are different, and therefore the third and fourth voltages are different as well. The third ambient temperature is lower than the fourth ambient temperature; the third voltage is greater than the fourth voltage. By bidirectionally adjusting the power supply voltage of the heating element, the power supply voltage can be reduced when the ambient temperature or the temperature of the thermistor is too high (or higher than the first warning temperature); and increased when the ambient temperature or the temperature of the thermistor is too low (or lower than the second warning temperature).

[0021] In one embodiment, the thermistor wire is made of platinum. Platinum thermistor wires exhibit higher sensitivity in terms of resistance changes with temperature.

[0022] In one embodiment, the fluid detection device is a microphone module, and the fluid is gas. This microphone module has the same technical effect as the fluid detection device provided in the foregoing embodiments, and will not be repeated here.

[0023] In one embodiment, the thermistor is also used to sense the flow of fluid in order to generate sensing signals such as sound signals.

[0024] In one embodiment, the fluid detection device further includes a substrate with a groove. A heating element and a thermistor are respectively disposed across both sides of the groove. The heating element and the thermistor have a suspended structure, which allows for better sensing of the flow of fluids such as gases. The groove is a channel, or a portion thereof.

[0025] On the other hand, this application provides a control method. The control method is applied to a controller in a fluid detection device, which further includes a voltage source, a channel for fluid flow, at least one heating element, and at least one thermistor. The heating element is electrically connected to the voltage source, and the thermistor is also electrically connected to the voltage source; wherein, when fluid flows in the channel, the fluid flows through the thermistor. The control method includes: first, the controller receives a first signal generated by the thermistor corresponding to the temperature of the thermistor. Next, when the ambient temperature of the thermistor is a first ambient temperature, the controller controls the voltage source to output at least a first voltage to the thermistor according to the first signal; when the ambient temperature of the thermistor is a second ambient temperature, the controller controls the voltage source to output at least a second voltage to the thermistor according to the first signal. Wherein, the first ambient temperature and the second ambient temperature are different, and the first voltage and the second voltage are different. The control method has the same technical effects as the fluid detection device provided in the foregoing embodiments, and will not be repeated here.

[0026] In one embodiment, the first ambient temperature is higher than the second ambient temperature. The first voltage is greater than the second voltage. The technical effects of the magnitude of the first ambient temperature, the second ambient temperature, the first voltage and the second voltage are as described above, and will not be repeated here.

[0027] In one embodiment, before the first signal is acquired, the method further comprises: receiving a first mode selection operation of a user, and then, in response to the first mode selection operation, the controller controls the voltage source to output a first mode initial voltage. Alternatively, before the first signal is acquired, the method further comprises: receiving a second mode selection operation of a user, and then, in response to the second mode selection operation, the controller controls the voltage source to output a second mode initial voltage. The technical effects of the mode selection are as described above, and will not be repeated here.

[0028] In one embodiment, the first mode initial voltage is 2V-4V. The second mode initial voltage is 5V-12V. The technical effects of the range of the first mode initial voltage and the range of the second mode initial voltage are as described above, and will not be repeated here.

[0029] In one embodiment, the first signal is used to represent the resistance of the thermistor. When the thermistor is a thermistor wire, the resistance value of the thermistor wire can be used as the first signal. The first signal can be an analog signal or a digital signal.

[0030] In one embodiment, when the ambient temperature where the thermistor is located is the first ambient temperature, the control voltage source outputs at least the first voltage to the thermistor according to the first signal, and when the ambient temperature where the thermistor is located is the second ambient temperature, the control voltage source outputs at least the second voltage to the thermistor according to the first signal, includes: first, from the first data set, the first ambient temperature or the second ambient temperature matched with the resistance value range where the resistance of the thermistor is located is obtained according to the first signal; wherein the first data set includes a plurality of resistance value ranges and a plurality of ambient temperatures; one resistance value range is matched with one ambient temperature, next, from the second data set, the first voltage matched with the ambient temperature range where the first ambient temperature is located is obtained, and the control voltage source outputs the first voltage, or from the second data set, the second voltage matched with the ambient temperature range where the second ambient temperature is located is obtained, and the control voltage source outputs the second voltage; wherein the second data set includes a plurality of ambient temperature ranges and a plurality of voltages; one ambient temperature range is matched with one voltage. Based on this, the fluid detection device can include a computer storage medium, such as a memory. The memory can store the first data set and the second data set described above. In this case, the first data set and the second data set composed of the voltages applied to the thermistor corresponding to each ambient temperature under different ambient temperatures can be obtained by simulation or experimental testing and the like under the condition that the performance of the fluid detection device, such as the sensitivity, signal-to-noise ratio and noise floor described above, is unchanged. And the above data set is stored in the memory. In this way, when the controller obtains the ambient temperature, the voltage matched with the ambient temperature can be called from the memory, and the above voltage source is controlled to provide at least the voltage to the thermistor, to reduce the fluctuation of the performance of the fluid detection device caused by the influence of the ambient temperature. Specifically, the controller is used to obtain the first signal representing the resistance of the thermistor, and according to the first signal, from the first data set, the first ambient temperature or the second ambient temperature matched with the resistance value range where the resistance is located is obtained. The controller is also used to obtain the first voltage matched with the ambient temperature range where the first ambient temperature is located from the second data set, and control the voltage source to output the first voltage, or obtain the second voltage matched with the ambient temperature range where the second ambient temperature is located from the second data set, and control the voltage source to output the second voltage.

[0031] In one embodiment, the first data set includes a first subset and a second subset. The first subset includes a plurality of resistance value ranges and a plurality of working temperature ranges. One resistance value range matches one working temperature range. The second subset includes a plurality of working temperature ranges and a plurality of ambient temperature ranges. One working temperature range matches one ambient temperature range. In this way, in order to improve the accuracy of the real-time resistance obtained by the controller in the fluid detection device, the first subset and the second subset of the working temperature corresponding to each ambient temperature under different ambient temperatures can be obtained by simulation or experimental test under the condition that the performance of the fluid detection device, such as the sensitivity, signal-to-noise ratio and background noise mentioned above, is unchanged. And store the above data set in the memory. Based on this, the controller is configured to obtain the first ambient temperature or the second ambient temperature matched with the resistance of the thermistor from the first data set according to the first signal, specifically including: the controller obtains the first working temperature range or the second working temperature range matched with the resistance value range where the resistance of the thermistor is located from the first subset, and obtains the first ambient temperature matched with the first working temperature range from the second subset, or obtains the second ambient temperature matched with the second working temperature range from the second subset.

[0032] In another aspect, the embodiments of the present application provide a fluid detection device. The fluid detection device includes a channel for fluid flow, at least one heating element, at least one thermistor, and a voltage converter, wherein the fluid flows through the thermistor when the fluid flows in the channel; the heating element is electrically connected with the voltage converter. The thermistor is electrically connected with the voltage converter, and the thermistor is configured to generate a first signal corresponding to the temperature of the thermistor. The voltage converter has a voltage terminal, the voltage terminal is electrically connected with the heating element and the thermistor, and the voltage converter is configured to output different voltages from the voltage terminal according to the first signal. The fluid detection device has the same technical effects as the fluid detection device provided by the above-mentioned embodiments, which will not be repeated here.

[0033] In another aspect, the embodiments of the present application provide an electronic device. The electronic device includes a housing and any one of the fluid detection devices described above, and the fluid detection device is arranged in the housing. The electronic device has the same technical effects as the fluid detection device provided by the above-mentioned embodiments, which will not be repeated here.

[0034] In another aspect, an embodiment of the present application provides a fluid detection device. The fluid detection device comprises a voltage source, a channel for fluid flow, at least one heating element, and at least one thermistor. The heating element is electrically connected to the voltage source. The thermistor is electrically connected to the voltage source. When fluid flows in the channel, the fluid flows through the thermistor, so as to facilitate the thermistor to detect the flow (e.g., flow rate) of the fluid (e.g., gas). The thermistor is configured to sense the ambient temperature of the thermistor, which is related to the temperature of the thermistor itself. When the ambient temperature of the thermistor is a third ambient temperature, the voltage source outputs a third voltage to the at least one heating element. When the ambient temperature of the thermistor is a fourth ambient temperature, the voltage source outputs a fourth voltage to the at least one heating element. The third ambient temperature and the fourth ambient temperature are different, and the third voltage and the fourth voltage are different. For example, the third ambient temperature is lower than the fourth ambient temperature, and the third voltage is greater than the fourth voltage.

[0035] In another aspect, an embodiment of the present application provides a fluid detection device. The fluid detection device comprises a voltage source, a channel for fluid flow, at least one heating element, and at least one thermistor. The heating element is electrically connected to the voltage source. The thermistor is electrically connected to the voltage source. When fluid flows in the channel, the fluid flows through the thermistor, so as to facilitate the thermistor to detect the flow (e.g., flow rate) of the fluid (e.g., gas). The thermistor is configured to sense the ambient temperature of the thermistor, which is related to the temperature of the thermistor itself. The at least one thermistor comprises a first thermistor and a second thermistor, and the first thermistor and the second thermistor are respectively used as two branches of a bridge circuit. The fluid detection device further comprises a first resistor connected in series between the voltage source and a ground terminal, a second resistor connected in series between the voltage source and the ground terminal, and an operational amplifier with a first input electrically connected between the first resistor and the first thermistor and a second input electrically connected between the second resistor and the second thermistor. The fluid detection device further comprises a comparator with a first input electrically connected to an end of the first thermistor or the second thermistor away from the voltage source, a second input for receiving a reference voltage, and an output for outputting a control signal, and a switch connected in series with the at least one heating element, with a gate receiving the control signal, and configured to selectively conduct based on the control signal.

[0036] In another aspect, embodiments of this application provide a fluid detection device. This fluid detection device includes a voltage source, a channel for fluid flow, at least one heating element, and at least one thermistor. The heating element is electrically connected to the voltage source. The thermistor is also electrically connected to the voltage source. When fluid flows in the channel, it passes through the thermistor, facilitating the thermistor's detection of the flow (e.g., flow rate) of fluids such as gases. When the fluid detection device operates in a first mode, the voltage source outputs a fifth voltage to the at least one thermistor; when the fluid detection device operates in a second mode, the voltage source outputs a sixth voltage to the at least one thermistor. For example, the first mode is a power-saving mode, the second mode is a high-performance mode, and the sixth voltage is greater than the fifth voltage. In some cases, when electronic devices are in different operating states (different functions are activated, etc.), the fluid detection device operates in different modes. Attached Figure Description

[0037] Figure 1A and Figure 1B This is a schematic diagram of the structure of a fluid detection device provided in an embodiment of this application;

[0038] Figure 2 This is a schematic diagram of another fluid detection device provided in an embodiment of this application;

[0039] Figure 3 This is a schematic diagram of the circuit structure of a microphone module provided in an embodiment of this application;

[0040] Figure 4A This is a schematic diagram of the structure of a microphone module provided in an embodiment of this application;

[0041] Figure 4B To and Figure 4A The diagram shows a circuit structure corresponding to the structure of the microphone module shown.

[0042] Figure 5A for Figure 4A The microphone module shown is a graph showing the spacing between the first thermistor wire (or the second thermistor wire) and the third thermistor wire, and the temperature change of the three thermistor wires.

[0043] Figure 5B for Figure 4A Another graph showing the spacing between the first thermistor wire (or the second thermistor wire) and the third thermistor wire in the microphone module shown, and the temperature change of the three thermistor wires.

[0044] Figure 6 To and Figure 4A The diagram shows another circuit structure corresponding to the structure of the microphone module shown.

[0045] Figure 7 Another schematic diagram of a circuit structure of a microphone module provided by an embodiment of the present application is shown in FIG. 10B.

[0046] Figure 8 Another schematic diagram of a circuit structure corresponding to the structure of the microphone module shown in FIG. 10A is shown in FIG. 10B. Figure 4A Another schematic diagram of a circuit structure corresponding to the structure of the microphone module shown in FIG. 10A is shown in FIG. 10B.

[0047] Figure 9 A schematic diagram of a structure of an electronic device provided by an embodiment of the present application is shown in FIG. 11.

[0048] Figure 10 A flowchart of a control method of a microphone module provided by an embodiment of the present application is shown in FIG. 12.

[0049] Figure 11A A mode selection schematic diagram of the electronic device shown in FIG. 11 is shown in FIG. 13. Figure 9 A mode selection schematic diagram of the electronic device shown in FIG. 11 is shown in FIG. 13.

[0050] Figure 11B A schematic diagram of a curve relationship between a vibration frequency of a particle and a sensitivity of a microphone module in a sound wave transmission process provided by an embodiment of the present application is shown in FIG. 14.

[0051] Figure 12 A schematic diagram of a structure of another microphone module provided by an embodiment of the present application is shown in FIG. 15A.

[0052] Figure 13 A schematic diagram of a structure of another microphone module provided by an embodiment of the present application is shown in FIG. 15A.

[0053] Figure 14 A schematic diagram of a structure of another microphone module provided by an embodiment of the present application is shown in FIG. 15A. Figure 10 A schematic diagram of a specific step of S102 in FIG. 15A is shown in FIG. 15B.

[0054] Figure 15 A schematic diagram of a circuit structure of another microphone module provided by an embodiment of the present application is shown in FIG. 16A.

[0055] Figure 16 A schematic diagram of a circuit structure of another microphone module provided by an embodiment of the present application is shown in FIG. 16A.

[0056] Figure 17 A schematic diagram of a circuit structure of another microphone module provided by an embodiment of the present application is shown in FIG. 16A.

[0057] Figure 18 A schematic diagram of a circuit structure of another microphone module provided by an embodiment of the present application is shown in FIG. 16A.

[0058] Figure 19 A schematic diagram of a circuit structure of another microphone module provided by an embodiment of the present application is shown in FIG. 16A.

[0059] Reference signs:

[0060] 01-fluid detection device; 11-heating element; 12-thermistor; 10-substrate; 100-groove; 30-voltage source; 40-controller; 101-electrode; 200-bridge circuit; 20a-first thermistor wire; 20b-second thermistor wire; Ra-first resistance; Rb-second resistance; 20c-third thermistor wire; 30a-first sub-voltage source; 30b-second sub-voltage source; 30c-third sub-voltage source; 03-electronic device; 300-housing; 301-display screen; 302-key; 50-memory; 401-control component; 402-processor circuit; 401a-first control circuit; 410a-voltage control circuit in the first control component; 420a-current collection circuit in the first control component; 401b-second control circuit; 410b-voltage control circuit in the second control component; 420b-current collection circuit in the second control component; 401c-voltage control circuit in the third control component; 410c-voltage control circuit in the third control component; 420c-current collection circuit in the third control component; 51-temperature detector; 60-comparator; 61-operational amplifier; 62-noise reduction circuit; 63-analog-to-digital converter; 64-digital signal processor; 70-voltage converter; 701-voltage terminal. DETAILED DESCRIPTION

[0061] The technical solutions in some embodiments of the present disclosure will be described clearly and completely in combination with the drawings. Obviously, the described embodiments are only some of the embodiments of the present disclosure, but not all. Based on the embodiments provided in the present disclosure, all other embodiments obtained by those skilled in the art belong to the scope of protection of the present disclosure.

[0062] Unless otherwise required by context, the term "comprise" and other forms thereof such as "comprises" and "comprising" are to be construed as open, inclusive, meaning that "comprising" means "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "example", or "some examples" are intended to mean that the particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of the present disclosure. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. In addition, the particular features, structures, materials, or characteristics described can be included in any suitable way in any one or more embodiments or examples.

[0063] Hereinafter, the terms "first", "second", and the like are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implying the number of the technical features indicated. Therefore, the features defined with "first", "second", and the like can explicitly or implicitly include one or more of the features.

[0064] In addition, in this application, the orientation terms such as "left", "right" and the like are defined with respect to the orientation of the components shown in the drawings, and it should be understood that these directional terms are relative concepts, which are used for relative description and clarification, and can be changed accordingly according to the change of the orientation of the components placed in the drawings.

[0065] In this application, unless otherwise explicitly specified and limited, the term "connection" should be understood broadly, for example, "connection" can be fixed connection, or detachable connection, or integral; can be directly connected, or indirectly connected through intermediate medium. In addition, "electrical connection" can be understood as "coupling", and "electrical connection" can be direct contact for electrical connection, or electrical connection through intermediate medium.

[0066] In the embodiments of the present application, "and / or" is only a description of the association relationship between the associated objects, which means that there can be three relationships, for example, A and / or B can represent the existence of A alone, the existence of A and B together, and the existence of B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects have an "or" relationship.

[0067] In the fields of aerospace, biochemical detection, medical instruments, etc., it is often necessary to measure some characteristics of fluid (such as liquid or airflow), for example, flow rate, flow, etc., to perform data analysis. In order to meet the development of fine industry and medical biological analysis, the measurement and control of fluid characteristics are required to be higher and higher. In order to improve the accuracy of fluid detection, it is necessary to reduce the influence of external environment, such as temperature, on the fluid detection device, so that the fluid detection device can be in the best performance state in different use environments, so that the fluid detection device can have high sensitivity and good signal-to-noise ratio in various use environments. In the following embodiments, the fluid is taken as an example of airflow.

[0068] In order to achieve the above purpose, the embodiment of the present application provides a fluid detection device 01 as shown in the figure. Figure 1A The fluid detection device can include a substrate 10, and at least one heating element 11 and at least one thermistor 12 disposed on the substrate 10. Figure 1A(The following description uses a heating element 11 and a thermistor 12 as an example.) The substrate 10 can be a silicon substrate, and a groove 100 can be formed on the substrate 10. The groove 100 can be formed by processes such as etching. The heating element 11 and the thermistor 12 are disposed across both sides of the groove 100, and the heating element 11 and the thermistor 12 are arranged side by side, for example, parallel to each other. In one embodiment, the groove 100 can serve as a channel for airflow L1. Fluid such as airflow L1 flows in the channel, and the thermistor 12 is located in the channel to detect the flow of fluid. When fluid such as airflow L1 flows through the groove 100 from the heating element 11 to the thermistor 12, or when airflow flows through the groove 100 from the thermistor 12 to the heating element 11, the groove 100 can serve as a channel for propagating sound waves (or airflow).

[0069] In one embodiment, the groove 100 can serve as part of a channel for airflow L1. For example, as Figure 1B As shown, the fluid detection device 01 also includes a packaging cover 10a. To clearly illustrate the structure of the fluid detection device 01, the outline of the packaging cover 10a is indicated by dashed lines. The packaging cover 10a includes a groove 100a corresponding to the recess 100. When the substrate 10 and the packaging cover 10a are packaged together, the packaging cover 10a is fastened onto the substrate 10, with the groove 100a directly opposite the groove 100. The groove 100a and the groove 100 form a channel in which fluid such as airflow L1 can flow. When fluid such as airflow L1 flows from the heating element 11 to the thermistor 12 through the channel formed by the groove 100 and the groove 100a, or when airflow flows from the thermistor 12 to the heating element 11 through the channel formed by the groove 100 and the groove 100a, the groove 100 can serve as a channel for propagating sound waves (or airflow). In other embodiments, the channel can also be formed in other ways. For example, the fluid detection device includes a hollow pipe, with the hollow portion inside the pipe serving as a channel for propagating sound waves (or airflow).

[0070] Based on this, a voltage can be applied to the heating element 11, and the heating element 11 generates heat to provide a temperature field for the thermistor 12. For example, the distance between the heating element 11 and the thermistor 12 can be less than or equal to 300 μm. In this way, the thermistor 12 can receive the temperature field generated by the heating element 11. The thermistor 12 can be used to generate a first signal corresponding to the temperature of the thermistor 12 under the action of the above-mentioned temperature field, and the temperature of the thermistor 12 reflects the ambient temperature of the thermistor 12. By detecting the first signal of the thermistor 12, the purpose of measuring the flow rate and flow of the gas can be achieved. In some embodiments, by detecting the first signal of the thermistor 12, the purpose of measuring the flow rate and flow of the gas can be achieved, so that the fluid detection device 01 can be used as a microphone (or microphone) for detecting sound waves.

[0071] For example, the above-mentioned thermistor 12 can be a thermistor wire. When the heating element 11 is powered on, the temperature field generated acts on the thermistor wire (i.e. the thermistor 12). At this time, when the gas flow passes through the thermistor wire in turn, the resistance of the thermistor wire changes under the action of the gas flow, so that the above-mentioned first signal for characterizing the resistance of the thermistor wire can be generated. The resistance of the thermistor wire is different at different temperatures. The size of the temperature change of the above-mentioned thermistor wire is related to the flow rate of the gas flow, so that by detecting the resistance of the thermistor wire, the purpose of measuring the flow rate and flow of the gas can be achieved.

[0072] Alternatively, for another example, the above-mentioned thermistor 12 and heating element 11 can both be thermistor wires, and the heating element 11 can also be a thermistor. For example, the thermistor is a first thermistor wire 20a as shown in Figure 2 , and the heating element 11 is a second thermistor wire 20b as shown in Figure 2The second thermistor wire 20b is shown. In this case, the first thermistor wire 20a and the second thermistor wire 20b can generate a temperature of 100K-600K after being powered, and thus the first thermistor wire 20a and the second thermistor wire 20b can both generate a temperature field. At this time, when the airflow flows through the first thermistor wire 20a and the second thermistor wire 20b in turn, or when the airflow flows through the second thermistor wire 20b and the first thermistor wire 20a in turn, the resistance values of the first thermistor wire 20a and the second thermistor wire 20b change under the action of the airflow. The thermistor can generate a first signal to represent the resistance value of the first thermistor wire 20a and / or the second thermistor wire 20b. Specifically, the airflow flowing through the first thermistor wire 20a and the second thermistor wire 20b changes the temperature field distribution of the fluid detection device 01, thereby generating a temperature gradient and causing a temperature difference between the two thermistor wires. The resistance value of the thermistor wire is different at different temperatures. The size of the above-mentioned temperature difference is related to the flow rate of the airflow, so that the flow rate and the flow of the gas can be measured by detecting the resistance values of the two thermistor wires. At this time, the first thermistor wire 20a and the second thermistor wire 20b can both serve as heating wires to provide a temperature field, and can both serve as sensitive wires that change according to the resistance value change caused by the temperature change.

[0073] The groove 100 can serve as a channel for the airflow L1, or the groove 100 serves as part of the channel, and the airflow L1 and other fluids flow in the channel. In addition, Figure 2 The fluid detection device 01 in the above embodiment can further include Figure 1B The packaging cover 10a in the above embodiment.

[0074] It should be noted that the materials and size specifications of the first thermistor wire 20a and the second thermistor wire 20b can be the same. Therefore, any one of the first thermistor wire 20a and the second thermistor wire 20b can serve as the above-mentioned thermistor 12, and the other wire serves as the heating element 11; or the first thermistor wire 20a and the second thermistor wire 20b serve as each other's heating element, and the first thermistor wire 20a and the second thermistor wire 20b are used together as a thermistor. At this time, the resistance value of any one or both of the first thermistor wire 20a and the second thermistor wire 20b under the action of the airflow can be reflected by the above-mentioned first signal.

[0075] In some embodiments of this application, the thermistor wire may have a positive temperature coefficient (PTC) effect. In this case, the resistance of the thermistor wire increases with increasing temperature. Alternatively, in other embodiments of this application, the thermistor wire may have a negative temperature coefficient (NTC) effect. In this case, the resistance of the thermistor wire decreases with increasing temperature. The following embodiments are all described using thermistor wires having a positive temperature coefficient effect and being resistance wires. In this case, the material constituting the thermistor wire may include platinum or copper, etc. In some embodiments, the first thermistor wire 20a and the second thermistor wire 20b may be spring-shaped or zigzag-shaped, such as... Figure 2 As shown, this can improve the reliability of the first thermistor wire 20a and the second thermistor wire 20b, and prevent them from melting due to excessive temperature.

[0076] As can be seen from the above, when the thermistor 12 is as follows Figure 2 The first thermistor wire 20a shown is such that the heating element 11 is as follows: Figure 2 In the case of the second thermistor wire 20b shown, when a voltage is applied to the first thermistor wire 20a and the second thermistor wire 20b, the resistance values ​​of the first thermistor wire 20a and the second thermistor wire 20b can change under the influence of airflow. Therefore, in order to apply a voltage to the first thermistor wire 20a and the second thermistor wire 20b, and to control the magnitude of the applied voltage, as follows... Figure 2 As shown, the fluid detection device 01 may further include a voltage source 30, a controller 40, and an electrode 101 disposed on the substrate 10. The electrode 101 is electrically connected to the first thermistor wire 20a and the second thermistor wire 20b.

[0077] It should be noted that the controller 40 mentioned above may be part of an application processor (AP) or other processor in an electronic device having the fluid detection device 01, or it may be a digital signal processor (DSP) independent of the application processor.

[0078] Based on this, the first thermistor wire 20a and the second thermistor wire 20b can be electrically connected with the voltage source 30 through the electrode 101. The voltage source 30 can apply a voltage to the first thermistor wire 20a and the second thermistor wire 20b through the electrode 101, and the voltage applied by the voltage source 30 to the first thermistor wire 20a and the second thermistor wire 20b can be the same or different. In addition, the controller 40 can be electrically connected with the voltage source 30. The controller 40 can be used to obtain a first signal for characterizing the resistance value (in some embodiments, it can be understood as the change of the resistance value) of the first thermistor wire 20a (and / or the second thermistor wire 20b), and control the voltage source 30 to output a first voltage U1 (having a first voltage value) when the ambient temperature of the first thermistor wire 20a (i.e., the thermistor 12) is a first ambient temperature T1, and output a second voltage U2 (having a second voltage value) when the ambient temperature of the first thermistor wire 20a (i.e., the thermistor 12) is a second ambient temperature T2, according to the first signal. Wherein, the first ambient temperature T1 and the second ambient temperature T2 are different, and the first voltage U1 and the second voltage U2 are different, i.e., the first voltage value and the second voltage value are different. In some embodiments of the present application, the first voltage U1 and the second voltage U2 can both be greater than zero.

[0079] In this case, when the fluid detection device 01 is at the first ambient temperature T1, at least the first thermistor wire 20a as the thermistor 11 can be applied with the first voltage U1 by the voltage source 30, so as to compensate for the fluctuation of the sensitivity, noise and other performance parameters of the first thermistor wire 20a due to temperature change, so that the fluid detection device 01 has higher sensitivity and good signal-to-noise ratio. When the use environment of the fluid detection device 01 changes, for example, the temperature changes from the first ambient temperature T1 to the second ambient temperature T2, at least the first thermistor wire 20a as the thermistor 11 can be applied with the second voltage U2 by the voltage source 30, so as to compensate for the fluctuation of the sensitivity, noise and other performance parameters of the first thermistor wire 20a due to temperature change, so that the fluid detection device 01 can still maintain higher sensitivity and good signal-to-noise ratio.

[0080] It should be noted that the voltage source 30 at least applies a voltage to the first thermistor wire 20a as the thermistor 11, which means that the controller 40 can apply different voltages to only the first thermistor wire 20a as the thermistor 11 through the voltage source 30 according to the first signal for characterizing the resistance of the thermistor. Alternatively, the controller 40 can apply different voltages to both the first thermistor wire 20a as the thermistor 11 and the second thermistor wire 20b as the heating element 11 through the voltage source 30 according to the first signal for characterizing the resistance of the thermistor.

[0081] In addition, the above description is based on the example that at least one of the heating element 11 and the thermistor 12 is a thermistor wire. In other embodiments of the present application, the heating element 11 can also be a heating rod made of metal or semiconductor material. The thermistor 12 can be a metal material, and the embodiments of the present application do not limit this. For the convenience of description, the following examples are still based on the example that at least one of the heating element 11 and the thermistor 12 is a thermistor wire. In some embodiments, the voltage source 30 can apply the same or different voltages to the heating element 11 and the thermistor 12.

[0082] The above description is based on the example that the fluid detection device 01 is applied to aerospace, biochemical detection, medical instruments, etc. to detect the flow rate and flow of the fluid. In other embodiments of the present application, a gas, such as air, can be used as a medium, and under the action of a sound wave, the particles (or particles, English for particle) in the air vibrate to transmit the sound wave.

[0083] In this case, the purpose of collecting a sound signal can be achieved by obtaining the particle velocity (or particle velocity) vector information of the gas (such as air) medium. In this way, the above fluid detection device 01 can also be applied to a sound system as a microphone (microphone, MIC) module to detect sound. In this case, the microphone module can also include a substrate 10, at least one heating element 11 and at least one thermistor 12 as shown in Figure 1A or a substrate 10, a first thermistor wire 20a, a second thermistor wire 20b, a voltage source 30, a controller 40 and an electrode 101 as shown in Figure 2 The connection mode and function of each component are the same as above, and will not be described here. In the case where the thermistor 12 is a first thermistor wire 20a as shown in Figure 2 and the heating element 11 is a second thermistor wire 20b as shown in Figure 2 The first thermistor wire 20a and the second thermistor wire 20b are applied with a voltage, and when a sound wave passes through the first thermistor wire 20a and the second thermistor wire 20b (two-wire model, i.e. the fluid detection device 01 includes two thermistor wires), the resistance of the first thermistor wire 20a and the second thermistor wire 20b can change under the action of the sound wave.

[0084] In one embodiment, the first thermistor wire 20a and the second thermistor wire 20b are applied with a voltage, and when a sound wave passes through the first thermistor wire 20a and the second thermistor wire 20b (two-wire model, i.e. the fluid detection device 01 includes two thermistor wires), the resistance of the first thermistor wire 20a and the second thermistor wire 20b can change under the action of the sound wave. Figure 2A voltage is applied to the first thermistor wire 20a and the second thermistor wire 20b, which heat up and generate a temperature field. When a sound wave is incident on either the first thermistor wire 20a or the second thermistor wire 20b, the reciprocating motion of particles in the air, acting as a medium, forms particle convection heat transfer, thereby transferring heat from the first thermistor wire 20a spanning both sides of the groove 100 to the second thermistor wire 20b (or vice versa). In some embodiments, when sound is transmitted from the first thermistor wire 20a side, the temperature of the first thermistor wire 20a decreases. In some embodiments, when sound is transmitted from the first thermistor wire 20a to the second thermistor wire 20b, the temperature of the second thermistor wire 20b increases. In some embodiments, when sound is transmitted from the second thermistor wire 20b side, the temperature of the second thermistor wire 20b decreases. In some embodiments, when sound travels from the second thermistor wire 20b to the first thermistor wire 20a, the temperature of the first thermistor wire 20a increases. This causes a change in the temperature field distribution of the fluid detection device 01, creating a temperature gradient and resulting in a temperature difference between the two thermistor wires 20a and 20b. The resistance values ​​of the first and second thermistor wires 20a and 20b differ at different temperatures. The magnitude of this temperature difference is related to the particle velocity. The resistance change of the first and / or second thermistor wires 20a and 20b can be converted into a voltage change, i.e., a voltage difference Δu0. By acquiring this voltage difference Δu0, the particle velocity can be measured, ultimately obtaining sound information.

[0085] The following example illustrates how the resistance changes of the first thermistor wire 20a and / or the second thermistor wire 20b can be converted into a voltage difference Δu0. For example, in some embodiments of this application, such as... Figure 3 As shown, the microphone module also includes a first resistor Ra and a second resistor Rb. The first end b1 of the first thermistor wire 20a and the first end c1 of the second thermistor wire 20b are electrically connected to the voltage source 30. The first end d1 of the first resistor Ra is electrically connected to the second end b2 of the first thermistor wire 20a, and the second end d2 of the first resistor Ra is grounded, so that the first resistor R1 is electrically connected between the first thermistor wire 20a and the ground terminal (GND). Furthermore, the first end e1 of the second resistor Rb is electrically connected to the second end c2 of the second thermistor wire 20b, and the second end e2 of the second resistor Rb is grounded, so that the second resistor Rb is electrically connected between the second thermistor wire 20b and the ground terminal (GND). In other embodiments, the first thermistor wire 20a or the second thermistor wire 20b can be replaced with a heating element located on one branch of the bridge circuit.

[0086] In this case, the first thermistor wire 20a, the second thermistor wire 20b, the first resistance Ra and the second resistance Rb can constitute a bridge circuit 200, and the first thermistor wire 20a and the second thermistor wire 20b are respectively two branches of the bridge circuit 200. The resistance values of the first resistance Ra and the second resistance Rb can be constant, for example, the resistance values of the first resistance Ra and the second resistance Rb are fixed. When the resistance values of the first thermistor wire 20a and / or the second thermistor wire 20b change with temperature, the voltage difference △u0 between the second end b2 of the first thermistor wire 20a and the second end c2 of the second thermistor wire 20b will change. In this way, the change of the resistance values of the first thermistor wire 20a and / or the second thermistor wire 20b can be converted into the voltage difference △u0. Thus, by obtaining the voltage difference △u0, the sound information can be obtained.

[0087] On this basis, when the air disturbance caused by the sound wave is transmitted to the first thermistor wire 20a or the second thermistor wire 20b, the relationship between the temperature change △T of at least one of the first thermistor wire 20a and the second thermistor wire 20b and the voltage difference △u0 can be obtained by the following formula.

[0088]

[0089]

[0090]

[0091]

[0092]

[0093] In the above formula, f is the frequency of the particle vibration; △T(f) is the function of the temperature change △T of the thermistor wire with respect to the frequency f; △T(0) is the temperature change when the frequency f is 0, i.e. direct current; wherein, △T(0) can be obtained by formula (4). f hc is the change of the frequency caused by the size, heat capacity and other parameters of the thermistor wire; f Da frequency variation caused by a parameter such as a thermal diffusion coefficient of air; D is a thermal diffusion coefficient of the medium; Lh is a cross-sectional area of the thermistor wire (e.g., the resistance wire); pi is a density of air; p2 is a density of the thermistor wire; P is a power of the thermistor wire; k is a thermal conductivity coefficient of the medium (e.g., air); a is a spacing between two adjacent thermistor wires; ly is a length of the thermistor wire (e.g., the resistance wire); g is an Euler constant (0.577); v is a vibration speed of a particle in the medium; U is a voltage applied to the thermistor wire; and p3 is a resistivity of the thermistor wire 20.

[0094] As can be seen from the above formula (1), formula (2), and formula (3), the temperature variation AT of the thermistor wire is proportional to the thermal diffusion coefficient D of the medium. That is, the greater the thermal diffusion coefficient D of the medium, the more obvious the temperature variation AT of the thermistor wire. In addition, as can be seen from formula (5), the greater the temperature variation AT of the thermistor wire, the greater the voltage difference Au0 converted from the resistance variation of the two thermistor wires.

[0095] The voltage difference Au0 converted from the resistance variation of the first thermistor wire 20a and / or the second thermistor wire 20b is proportional to the sensitivity of the microphone module. The sensitivity can be defined as a voltage (in V) output by the microphone module when the output end is open when a unit sound pressure (in Pa) acts on the thermistor wire, that is, the unit of the sensitivity is V / Pa. Therefore, the greater the temperature variation AT of the thermistor wire 20, the higher the sensitivity of the microphone module.

[0096] Therefore, in order to improve the sensitivity of the microphone module, the thermal diffusion coefficient D of the medium can be increased. Based on this, in some other embodiments of the present application, the microphone module 02 provided by the embodiments of the present application can include one heating element 11 and two thermistors 12. The two thermistors 12 can be the first thermistor wire 20a and the second thermistor wire 20b as shown in Figure 4A Alternatively, in some other embodiments of the present application, the heating element 11 can be a third thermistor wire 20c as shown in Figure 4B At this time, the microphone module 02 is a three-wire model (i.e., the microphone module 02 includes three thermistor wires). The third thermistor wire 20c is located between the first thermistor wire 20a and the second thermistor wire 20b to heat the first thermistor wire 20a and the second thermistor wire 20b. The first thermistor wire 20a and the second thermistor wire 20b can be symmetrically arranged about the third thermistor wire 20c. As shown in Figure 4BAs shown, the first end g1 of the third thermistor wire 20c can be electrically connected with the voltage source 30, and the second end g2 of the third thermistor wire 20c can be grounded. The third thermistor wire 20c is different from the first thermistor wire 20a and the second thermistor wire 20b in that the third thermistor wire 20c is not connected into the bridge circuit 200. In this case, when the voltage source 30 can apply a voltage to the third thermistor wire 20c, the heat generated by the third thermistor wire 20c can heat the first thermistor wire 20a and the second thermistor wire 20b, so as to increase the heat dissipation coefficient D of the medium (i.e., air) around the first thermistor wire 20a and the second thermistor wire 20b, increase the temperature change AT of the first thermistor wire 20a and the second thermistor wire 20b, and achieve the purpose of improving the sensitivity of the microphone module. The distance between the first thermistor wire 20a or the second thermistor wire 20b and the third thermistor wire 20c can be less than or equal to 300 μm. In this way, the first thermistor wire 20a and the second thermistor wire 20b can receive the temperature field generated by the third thermistor wire 20c.

[0097] In this case, the first thermistor wire 20a and the second thermistor wire 20b serve as sensitive wires to convert the resistance change into a voltage difference Au0. The third thermistor wire 20c can serve as a heating wire to provide a temperature field to the first thermistor wire 20a and the second thermistor wire 20b by self-heating. It should be noted that the materials and size specifications of the first thermistor wire 20a and the second thermistor wire 20b can be the same. In addition, the third thermistor wire 20c can have the same material and size specifications as the first thermistor wire 20a. Based on this, in order to facilitate the improvement of the heat dissipation coefficient D of the medium around the first thermistor wire 20a and the second thermistor wire 20b, a higher voltage can be provided to the third thermistor wire 20c to increase the heat generated by the third thermistor wire 20c. Alternatively, in other embodiments, the third thermistor wire 20c can have different materials and size specifications from the first thermistor wire 20a. Based on this, in order to facilitate the improvement of the heat dissipation coefficient D of the medium around the first thermistor wire 20a and the second thermistor wire 20b, the materials and size specifications of the third thermistor wire 20c can be adjusted so that when the first thermistor wire 20a, the second thermistor wire 20b, and the third thermistor wire 20c receive the same voltage, the third thermistor wire 20c generates more heat.

[0098] When the microphone module 02 includes the first thermistor wire 20a, the second thermistor wire 20b, and the third thermistor wire 20c, the spacing (in μm) between the first thermistor wire 20a (or the second thermistor wire 20b) and the third thermistor wire 20c, and the temperature (in K) change curves of the three thermistor wires are shown in the figure. Figure 5A and Figure 5B As shown.

[0099] Among them, such as Figure 5A As shown, point A3 has an x-coordinate of 0 μm. Point A3 indicates that the temperature of the third thermistor wire 20c, located in the middle, is 960 K. The third thermistor wire 20c has the highest temperature, and point A3 is at the highest temperature. The temperature decreases as the distance from the third thermistor wire 20c increases. Figure 5A In the diagram, the positive coordinate represents the distance from the third thermistor wire 20c in the first direction X, and the negative coordinate represents the distance from the third thermistor wire 20c in the opposite direction of the first direction X. When the distance between the first thermistor wire 20a (or the second thermistor wire 20b) and the third thermistor wire 20c increases, the temperature of the first thermistor wire 20a (or the second thermistor wire 20b) decreases.

[0100] When no sound wave is incident on the first thermistor wire 20a (or the second thermistor wire 20b), and assuming the first and second thermistor wires 20a and 20b are symmetrically arranged about the third thermistor wire 20c, the temperature of the first thermistor wire 20a at point A1 (in the opposite direction of the first direction X, for example, on the left, with a distance of 100 μm from the third thermistor wire 20c) and the temperature of the second thermistor wire 20b at point A2 (in the first direction X, for example, on the right, with a distance of 100 μm from the third thermistor wire 20c) are equal, both being 750 K. Points A1 and A2 are both at a peak value because the first and second thermistor wires 20a and 20b also heat up when a voltage is applied.

[0101] When sound waves are like Figure 4A As shown, when the sound wave is incident from the side where the first thermistor wire 20a is located (i.e., the left side), the first thermistor wire 20a near the side where the sound wave is located is cooled, and the temperature of the first thermistor wire 20a is as follows: Figure 5B The K temperature decreases, for example, to around 725 K (point A1). However, the heat transfer from the reciprocating motion of the medium particles is transferred to the second thermistor wire 20b on the side away from the sound wave, causing the heat in the second thermistor wire 20b to increase, for example, to around 800 K (point A2).

[0102] Because sound travels through a medium, the particles within it will move back and forth. For example, the particles will move not only from the first thermistor wire 20a towards the second thermistor wire 20b (e.g., from...). Figure 4A The second thermistor wire 20b moves from the left end to the right end, and also moves from the right end to the left end of the first thermistor wire 20a. Therefore, when the medium particle, the second thermistor wire 20b, moves towards the first thermistor wire 20a, its temperature decreases, and the heat of the first thermistor wire 20a increases. In this situation, the temperature changes of the first and second thermistor wires 20a and 20b will cause changes in their resistance, which in turn will lead to… Figure 4B The voltage difference Δu0 between the second end b2 of the first thermistor wire 20a and the second end c2 of the second thermistor wire 20b changes. As explained above, this converts the resistance change of the first thermistor wire 20a and the second thermistor wire 20b into a voltage difference Δu0. Therefore, by obtaining this voltage difference Δu0, sound information can be acquired.

[0103] It should be noted that the above description uses the microphone module 02 as a three-wire model (i.e., including the first thermistor wire 20a, the second thermistor wire 20b, and the third thermistor wire 20c) as an example, and combines the temperature curve of the thermistor wire with the spacing between the thermistor wires to explain the temperature change of the first thermistor wire 20a or the second thermistor wire 20b when sound waves are incident on it.

[0104] When the microphone module 02 is a two-wire model (i.e., including a first thermistor wire 20a and a second thermistor wire 20b), the first thermistor wire 20a and the second thermistor wire 20b can serve as sensitive wires, converting changes in resistance into a voltage difference Δu0, and can also serve as heating wires, providing a temperature field through their own heating. In this case, whether the sound wave is not incident on the thermistor wire or is incident on the thermistor wire, the curve showing the change in temperature of the thermistor wire relative to the distance between the thermistor wires is as described above, and will not be repeated here. The difference is that the distance on the horizontal axis of the above curve is the distance between the first thermistor wire 20a and the second thermistor wire 20b.

[0105] As can be seen from the above, when the microphone module 02 is a three-wire model, the microphone module 02 includes one heating wire (for example, the third thermistor wire 20c) located in the middle position, and two sensitive wires (for example, the first thermistor wire 20a and the second thermistor wire 20b) located on both sides of the heating wire. In some other embodiments of the present application, two or more sensitive wires can be arranged in parallel on one side of the heating wire, and the number of sensitive wires on both sides of the heating wire can be the same. The present application does not limit the number of sensitive wires, as long as the sensitive wires can be connected to the voltage source 30 and the controller 40. Figure 4B The bridge circuit 200 shown in FIG. 2 can be used.

[0106] As can be seen from the above, the resistance of the thermistor wire as the sensitive wire can change under the action of airflow, for example, the sound wave signal. In this case, the microphone module 02 can be called a hot-wire type vector microphone module or an acoustic vector sensor (AVS) module. Compared with the diaphragm type vector microphone module with poor frequency response consistency and the cilium type vector microphone module with high processing difficulty, the AVS module has the advantages of being applicable to industrial measurement, high signal-to-noise ratio, simple processing, and the like.

[0107] As can be seen from the above, in order to provide voltage to each thermistor wire, in some embodiments of the present application, as shown in FIG. 2, the first thermistor wire 20a, the second thermistor wire 20b, and the third thermistor wire 20c are connected to the same voltage source 30. Based on this, in the case where the microphone module 02 further includes a controller 40 connected to the voltage source 30, as shown in FIG. 2, the controller 40 can obtain the first signal (used to represent the resistance of the thermistor wire) of at least one of the first thermistor wire 20a, the second thermistor wire 20b, and the third thermistor wire 20c, and control the voltage source 30 to output the first voltage U1 at the first environmental temperature T1 and output the second voltage U2 at the second environmental temperature T1 according to the first signal. Figure 4B Figure 6

[0108] ​​In this case, when the microphone module 02 is at the first ambient temperature T1, the first voltage U1 can be applied to any one, two or three of the first thermistor wire 20a, the second thermistor wire 20b and the third thermistor wire 20c by the voltage source 30 described above, so that the microphone module 02 has high sensitivity and good signal-to-noise ratio. When the use environment of the microphone module 02 changes, for example, the temperature changes from the first ambient temperature T1 described above to the second ambient temperature T2, the second voltage U2 can be applied to any one, two or three of the first thermistor wire 20a, the second thermistor wire 20b and the third thermistor wire 20c by the voltage source 30 described above, so that the microphone module 02 can still maintain high sensitivity and good signal-to-noise ratio.

[0109] It should be noted that the above is an example of the control method of the controller 40, taking the microphone module 02 as a three-wire model, that is, including the first thermistor wire 20a, the second thermistor wire 20b and the third thermistor wire 20c three thermistor wires. When the microphone module 02 is a two-wire model, that is, including the first thermistor wire 20a and the second thermistor wire 20b two thermistor wires, the controller 40 controls as described above. In some embodiments, the first thermistor wire 20a and the second thermistor wire 20b can receive the same voltage output by the voltage source 30 at the same ambient temperature, and the specific control process will not be described here. Figure 3

[0110] The above is an example of the microphone module 02 connecting multiple thermistor wires to the same voltage source 40. In some embodiments of the present application, when the microphone module 02 is a two-wire model (i.e., including the first thermistor wire 20a and the second thermistor wire 20b), as shown in Figure 7 the microphone module 02 can include two sub-voltage sources, namely the first sub-voltage source 30a and the second sub-voltage source 30b, for example, the voltage source includes two sub-voltage sources, namely the first sub-voltage source 30a and the second sub-voltage source 30b. The first end b1 of the first thermistor wire 20a is electrically connected to the first sub-voltage source 30a, and the first end c1 of the second thermistor wire 20b is electrically connected to the second sub-voltage source 30b. In addition, the first sub-voltage source 30a and the second sub-voltage source 30b described above are electrically connected to the controller 40.

[0111] ​In this case, the controller 40 can learn the external ambient temperature according to the resistance value change of the thermistor, and control the voltage applied to the first thermistor wire 20a and / or the second thermistor wire 20b by different voltage sources, so that the performance of the microphone module 02 does not fluctuate greatly with the change of the ambient temperature. In addition, at the same ambient temperature, the voltages output by the first sub-voltage source 30a and the second sub-voltage source 30b can be the same, so that the load of the first sub-voltage source 30a and the second sub-voltage source 30b can be reduced compared with the scheme of using two thermistor wires to share one voltage source, so as to achieve the purpose of reducing power consumption.

[0112] Similarly, in some embodiments of the present application, when the microphone module 02 is a three-wire model (i.e., including the first thermistor wire 20a, the second thermistor wire 20b, and the third thermistor wire 20c), as shown in Figure 8 The microphone module 02 can include three voltage sources, i.e., the first sub-voltage source 30a, the second sub-voltage source 30b, and the third sub-voltage source 30c. The first end b1 of the first thermistor wire 20a is electrically connected to the first sub-voltage source 30a, the first end c1 of the second thermistor wire 20b is electrically connected to the second sub-voltage source 30b, and the first end g1 of the third thermistor wire 20c is electrically connected to the third sub-voltage source 30c.

[0113] In some embodiments, one voltage source can also have multiple output ends, and different output ends can be electrically connected to different elements, such as thermistor wires, thermistors, or heating elements. Different output ends can output the same voltage or different voltages to power different elements. For example, the first output end of the voltage source powers the first thermistor wire 20a, and the second output end of the voltage source powers the second thermistor wire 20b. In some embodiments, the same output end of one voltage source can be connected to different elements to provide the same voltage to different elements. For example, one voltage source can simultaneously provide the same voltage to two thermistors. In some embodiments, the voltage source can be a voltage converter, etc.

[0114] In addition, the above-mentioned first sub-voltage source 30a, second sub-voltage source 30b, and third sub-voltage source 30c are electrically connected to the controller 40. In this case, the controller 40 can control the voltage applied to the first thermistor wire 20a, the second thermistor wire 20b, and the third thermistor wire 20c by different voltage sources according to the external ambient temperature, so that the performance of the microphone module 02 does not fluctuate greatly with the change of the ambient temperature.

[0115] Based on this, the aforementioned fluid detection device 01, such as the microphone module 02, can be applied to any electronic device with voice recognition or voice call functionality. For example, this electronic device could be a high-powered television, desktop computer, all-in-one computer, smart speaker, in-vehicle voice recognition device, etc. Alternatively, the electronic device could also be a low-powered tablet computer, mobile phone, smartwatch, etc. Taking an electronic device as an example... Figure 9 Taking the television set 03 shown as an example, the television set 03 may include a housing 300, a display screen 301 located within the housing 300, and a microphone module 02 disposed below the display screen. This electronic device 03 has the same technical effect as the microphone module 02 provided in the aforementioned embodiment. Therefore, in an electronic device having the aforementioned microphone module 02, the performance of the microphone module 02 will not fluctuate significantly with changes in ambient temperature when the user's ambient temperature is different.

[0116] It should be noted that this application does not limit the type of the aforementioned display screen, which may be a liquid crystal display screen, an organic electroluminescent display screen, or a quantum dot electroluminescent display screen.

[0117] The following uses electronic device 03 with microphone module 02 as an example. Figure 9 The television shown, and the microphone module 02 is as follows Figure 8 Taking the three-wire model shown as an example, the structure of the controller 40 and the control method of applying voltage to each thermistor wire according to temperature control will be explained in detail. The microphone module 02 can be located anywhere on the television, for example, it can be located on the bottom bezel of the television (e.g.,...). Figure 9 (As shown), the top border, left border, right border, or located behind the display screen 301. The control method of the controller 40 includes, for example: Figure 10 S100 to S102 are shown.

[0118] S100, Receive user mode selection operation.

[0119] For example, the operating modes of the microphone module 02 described above may include a first mode (e.g., power-saving mode) and a second mode (e.g., high-performance mode). In power-saving mode, the microphone module 02 consumes less power, but the electrical signal output by the microphone module 02 is also lower (e.g., Figure 8 When the voltage difference Δu0 is small, and / or the supply voltage provided by the voltage source to the heating element and / or thermistor is small, the performance (e.g., sensitivity) of the microphone module 02 is poor. Conversely, in high-performance mode, the power consumption of the microphone module 02 is higher, but the output electrical signal of the microphone module 02 is higher (e.g., Figure 8When the voltage difference Δu0 is large, and / or the supply voltage provided by the voltage source to the heating element and / or the thermistor is large, the microphone module 02 performs better.

[0120] For example, when the microphone module 02 is applied to a television, if the television is playing images and sound and does not require calls or voice recognition, the user's sensitivity requirements for the microphone module 02 are low. In this case, the microphone module 02 can operate in power-saving mode. Alternatively, if the television is performing voice recognition or voice calls, the user's sensitivity requirements for the microphone module 02 are higher. In this case, the microphone module 02 can operate in high-performance mode.

[0121] In this case, before the microphone module 02 performs voice recognition or voice calls, the user can select the operating mode of the microphone module 02 as needed, or the electronic device can automatically determine whether to enter a power-saving mode or a high-performance mode based on the current state. In some embodiments of this application, the user can use a TV remote control, such as... Figure 11A As shown, in the settings interface of the display screen 301 of the television (electronic device 03), the power-saving mode and high-performance mode can be selected by controlling the position of the selection button 302. For example, the selection button 302 being on the left indicates that the microphone module 02 is in working mode, and the selection button 302 being on the right indicates that the microphone module 02 is in working mode. In some embodiments, the power-saving mode or high-performance mode can also be selected for the television via a mobile phone. In some embodiments, the electronic device can automatically determine whether to enter the power-saving mode or high-performance mode based on one or more of the currently running software, programs, or functions. For example, when the user turns on the voice call function of the electronic device, or when the electronic device is using its own microphone for voice communication, the microphone module 02 automatically enters the high-performance mode; or, if the electronic device can perform voice recognition, when the electronic device is not woken up by voice, the microphone module 02 is in power-saving mode, and when the electronic device is woken up by voice (e.g., the user calls the wake-up word "Xiaoyi Xiaoyi" to wake up the smart voice system), the electronic device needs to recognize the user's semantics, and the microphone module 02 automatically enters the high-performance mode.

[0122] Based on this, in some embodiments of this application, when the user performs a first mode selection operation, the selection button 302 corresponding to the power saving mode is located on the left, so that the power saving mode is in the enabled state. In this case, the controller 40 performs the above-mentioned S100, specifically including: the controller 40 receives the user's above-mentioned first mode selection operation, and in response to the first mode selection operation, controls the voltage source, for example... Figure 8 The first sub-voltage source 30a, the second sub-voltage source 30b, and the third sub-voltage source 30c shown output the initial voltage U1 of the first mode.

[0123] Alternatively, in some other embodiments of the present application, when the user performs the second mode selection operation, Figure 11A The selection key 302 corresponding to the high performance mode is shown on the left side, so that the high performance mode is in the on state. In this case, the controller 40 performs the above S100 specifically includes: the controller 40 receives the above-mentioned second mode selection operation of the user, and in response to the second mode selection operation, controls the voltage source, for example Figure 8 The first sub-voltage source 30a, the second sub-voltage source 30b and the third sub-voltage source 30c shown output the second mode initial voltage U2.

[0124] The following describes the setting method of the first mode initial voltage U1 and the second mode initial voltage U2. FIG. 11B is a curve relationship between the vibration frequency of the particle and the sensitivity of the microphone module 02 during the sound wave transmission process. When the voltage U applied to the first and second thermistor wires 20a and 20b is different, the above-mentioned curves (for example, curve ①, curve ② and curve ③) are different.

[0125] Specifically, the voltage U applied to the first and second thermistor wires 20a and 20b of the curve ①, curve ② and curve ③ increases in turn. In this case, when the vibration frequency of the particle is constant, for example, 2000 Hz, from the above three curves, it can be seen that the greater the voltage U applied to the first and second thermistor wires 20a and 20b, the higher the sensitivity of the microphone module 02, and the better the performance of the microphone module 01. Conversely, the smaller the voltage U applied to the first and second thermistor wires 20a and 20b, the lower the sensitivity of the microphone module 02, and the worse the performance of the microphone module 01.

[0126] In addition, the relationship between the voltage U applied to the first and second thermistor wires 20a and 20b and the performance of the microphone module 02 (including: sensitivity, signal-to-noise ratio and noise floor) can also be shown in Table 1.

[0127] Table 1

[0128]

[0129] As can be seen from Table 1, the higher the voltage U applied to the first thermistor wire 20a and the second thermistor wire 20b, the higher the sensitivity of the microphone module 02 and the higher the signal-to-noise ratio, but the noise floor will increase. Conversely, the lower the voltage U applied to the first thermistor wire 20a and the second thermistor wire 20b, the lower the sensitivity of the microphone module 02 and the lower the signal-to-noise ratio, but the noise floor will decrease. Furthermore, Table 1 shows that the effect of voltage change on noise floor is relatively small compared to the effect of voltage change on sensitivity and signal-to-noise ratio. Therefore, considering sensitivity and signal-to-noise ratio as the main factors affecting the performance of the microphone module 02, the initial voltage U2 of the second mode provided to the thermistor wire in high-performance mode can be greater than the initial voltage U1 of the first mode provided to the thermistor wire in power-saving mode.

[0130] For example, the initial voltage U1 of the first mode can be 2V to 4V. When the initial voltage U1 of the first mode is less than 2V, the voltage applied to the thermistor wire is too small, resulting in low sensitivity of the microphone module 02 and affecting its performance. Furthermore, when the initial voltage U1 of the first mode is greater than 4V, the voltage applied to the thermistor wire is too large, increasing the power consumption of the microphone module 02 and reducing its power-saving effect. In some embodiments of this application, the initial voltage U1 of the first mode can be 2V, 2.5V, 3V, 3.5V, or 4V.

[0131] Furthermore, the initial voltage U2 for the second mode can be between 5V and 12V. When the initial voltage U2 for the second mode is less than 5V, the voltage applied to the thermistor wire is too low, resulting in low sensitivity of the microphone module 02, which is detrimental to achieving high performance standards. Conversely, when the initial voltage U2 for the second mode is greater than 12V, the voltage applied to the thermistor wire is too high, increasing the power consumption of the microphone module 02, causing severe overheating of the thermistor wire, and increasing the risk of thermistor wire failure. In some embodiments of this application, the initial voltage U2 for the second mode can be 5V, 6V, 7V, 8V, 9V, 10V, 11V, or 12V.

[0132] It should be noted that the above refers to the user using a TV remote control to... Figure 11A In the settings interface of the television display screen 301 shown, the first mode selection operation or the second mode selection operation is performed by controlling the position of the selection button 302. This explanation uses the selection of power-saving mode or high-performance mode as an example. In some other embodiments of this application, the user can also directly press the mode button on the television remote control to perform the first mode selection operation or the second mode selection operation.

[0133] Alternatively, in some other embodiments of the present application, when the television set can be electrically connected with a mobile terminal, such as a mobile phone or a tablet computer, of the user through a wireless manner, the user can also perform the above-mentioned first mode selection operation or second mode selection operation by controlling a selection button in an operation interface of the mobile terminal. The present application does not limit this.

[0134] Based on this, in order to enable the controller 40 to obtain the first mode initial voltage U1 and the second mode initial voltage U2 according to the mode selection operation of the user, the microphone module 02 can further include a memory 50 as shown in the figure, which is electrically connected with the controller 40. The first mode initial voltage U1 and the second mode initial voltage U2 are stored in the memory 50. Figure 12

[0135] In this case, when the controller 40 receives the first mode selection operation issued by the user, the first mode initial voltage U1 can be obtained from the memory 50 in response to the first mode selection operation, and the first sub-voltage source 30a, the second sub-voltage source 30b and the third sub-voltage source 30c are controlled to output the first mode initial voltage U1 to the thermistor wires to which they are respectively electrically connected. Similarly, when the controller 40 receives the second mode selection operation issued by the user, the second mode initial voltage U2 can be obtained from the memory 50 in response to the second mode selection operation, and the first sub-voltage source 30a, the second sub-voltage source 30b and the third sub-voltage source 30c are controlled to output the second mode initial voltage U2 to the thermistor wires to which they are respectively electrically connected.

[0136] The specific structure of the above-mentioned controller 40 is exemplified as follows. In some embodiments of the present application, as shown in the figure, the controller 40 can include at least one control component (for example, a first control component 401a, a second control component 401b and a third control component 401c), and a processor circuit 402. Figure 13

[0137] Among them, any one or more of the first control component 401a, the second control component 401b and the third control component 401c can include a voltage control circuit. In this case, the voltage control circuit 410a in the first control component 401a is electrically connected with the first sub-voltage source 30a and the processor circuit 402. The voltage control circuit 410b in the second control component 401b is electrically connected with the second sub-voltage source 30b and the processor circuit 402. The voltage control circuit 410c in the third control component 401c is electrically connected with the third sub-voltage source 30c and the processor circuit 402. Any one of the above-mentioned voltage control circuits is used to control the voltage output by the voltage source to which the voltage control circuit is electrically connected according to the voltage control instruction output by the processor circuit 402. ​​

[0138] In this case, when the processor circuit 402 in the controller 40 receives a first mode selection operation issued by the user, the processor circuit 402 can acquire the first mode initial voltage U1 from the memory 50 in response to the first mode selection operation, and output a voltage control instruction to the voltage control circuit in the first control component 401a, the second control component 401b, and the third control component 401c. The voltage control circuit 410a in the first control component 401a controls the first sub-voltage source 30a electrically connected thereto to output the first mode initial voltage U1 according to the voltage control instruction. The voltage control circuit 410b in the second control component 401b controls the second sub-voltage source 30b electrically connected thereto to output the first mode initial voltage U1 according to the voltage control instruction. The voltage control circuit 410c in the third control component 401c controls the third sub-voltage source 30c electrically connected thereto to output the first mode initial voltage U1 according to the voltage control instruction.

[0139] Similarly, when the processor circuit 402 in the controller 40 receives a second mode selection operation issued by the user, the processor circuit 402 can acquire the second mode initial voltage U2 from the memory 50 in response to the second mode selection operation, and output a voltage control instruction to the voltage control circuit in the first control component 401a, the second control component 401b, and the third control component 401c. The voltage control circuit 410a in the first control component 401a controls the first sub-voltage source 30a electrically connected thereto to output the second mode initial voltage U2 according to the voltage control instruction. The voltage control circuit 410b in the second control component 401b controls the second sub-voltage source 30b electrically connected thereto to output the second mode initial voltage U2 according to the voltage control instruction. The voltage control circuit 410c in the third control component 401c controls the third sub-voltage source 30c electrically connected thereto to output the second mode initial voltage U2 according to the voltage control instruction.

[0140] In some embodiments of the present application, any one of the above-mentioned voltage control circuits (for example, the voltage control circuit 410a) can include a digital to analog converter (DAC) and a power amplifier. The DAC is used to convert the digital signal output by the processor circuit 402, i.e., the above-mentioned voltage control instruction, into an analog voltage output to the power amplifier. The power amplifier amplifies the above-mentioned analog voltage and outputs it to the voltage source (for example, the first sub-voltage source 30a) electrically connected to the voltage control circuit (for example, the voltage control circuit 410a), so that the first sub-voltage source 30a outputs the above-mentioned analog voltage signal.

[0141] In the case of determining the working mode of the microphone module 02, when the ambient temperature changes, in order to ensure that the performance of the microphone module 02 will not fluctuate greatly, the control process of the microphone module 02 further includes the following S101 and S102.

[0142] S101, obtaining a first signal.

[0143] As can be seen from the above, the thermistor can generate a first signal corresponding to the temperature, and the first signal is used to represent the resistance value of the thermistor. Taking the microphone module 02 including two thermistors as an example, the first thermistor wire 20a and the second thermistor wire 20b, the resistance value of the first thermistor wire 20a or the second thermistor wire 20b can change according to the change of temperature. For example, the first signal reflects the resistance value of the first thermistor wire 20a or the second thermistor wire 20b, for example, the first signal can be the resistance value of the first thermistor wire 20a or the second thermistor wire 20b, or the current I output by the voltage source to the thermistor wire collected by the controller 40. In some implementations, the controller 40 performing S101 to obtain the first signal can include: the controller 40 collects the current I (i.e. the current signal) output by the voltage source to the thermistor wire, and obtains the resistance R of the thermistor wire according to the collected current I and the voltage U output by the voltage source (R=U / I). In some embodiments, the first signal can also be the voltage difference △u0 in the bridge circuit, the voltage difference △u0 can represent the resistance value of the thermistor, and the change of the voltage difference △u0 reflects the change of the resistance value of the thermistor. In some embodiments, the first signal can also be the voltage value of the second end b2 of the first thermistor wire 20a, and / or the voltage value of the second end c2 of the second thermistor wire 20b, the change of the voltage value of the second end b2 of the first thermistor wire 20a can reflect the change of the resistance value of the first thermistor wire 20a, and the change of the voltage value of the second end c2 of the second thermistor wire 20b can reflect the change of the resistance value of the second thermistor wire 20b.

[0144] In some embodiments, in the case of the microphone module 02 being the three-wire model, in order to enable the controller 40 to obtain the resistance of different thermistor wires, as shown in Figure 13 Any one of the first control component 401a, the second control component 401b and the third control component 401c in the controller 40 further includes a current collection circuit. The current collection circuit 420a in the first control component 401a is electrically connected with the first sub-voltage source 30a, and the current collection circuit 420a is used to collect the current output by the first sub-voltage source 30a to the first thermistor wire 20a.

[0145] Similarly, the current acquisition circuit 420b in the second control component 401b is electrically connected to the second sub-voltage source 30b, and this current acquisition circuit 420b is used to acquire the current output by the second sub-voltage source 30b to the second thermistor wire 20b. The current acquisition circuit 420c in the third control component 401c is electrically connected to the third sub-voltage source 30c, and this current acquisition circuit 420c is used to acquire the current output by the third sub-voltage source 30c to the second thermistor wire 20c.

[0146] In this case, the processor circuit 402, which is electrically connected to each of the aforementioned current acquisition circuits, can calculate the resistance Ra of the first thermistor wire 20a based on the voltage output from the first sub-voltage source 30a and the current acquired by the current acquisition circuit 420a in the first control component 401a. The processor circuit 402 can also calculate the resistance Rb of the second thermistor wire 20b based on the voltage output from the second sub-voltage source 30b and the current acquired by the current acquisition circuit 420b in the second control component 401b. If the first thermistor wire 20a and the second thermistor wire 20b have the same material and dimensions, the resistances obtained by the processor circuit 402 can be the same. Therefore, the resistance Ra of the first thermistor wire 20a or the resistance Rb of the second thermistor wire 20b can be used as the resistance obtained by the processor circuit 402.

[0147] However, when sound waves are like Figure 13 As shown, when the sound wave is incident from the side where the first thermistor wire 20a is located (i.e., the left side), the first thermistor wire 20a near the side where the sound wave is located is cooled, and the temperature of the first thermistor wire 20a is as follows: Figure 5B The figure shows a decrease, for example, as shown. Figure 13 As shown, the temperature of the first thermistor wire 20a drops to Ta-ΔT. Furthermore, the heat transfer from the reciprocating motion of the medium particles is transferred to the second thermistor wire 20b on the side away from the sound wave, causing an increase in the heat of the second thermistor wire 20b, for example... Figure 13 As shown, the temperature of the second thermistor wire 20b increases to Tb+ΔT.

[0148] In the case where the first and second thermistor wires 20a and 20b have the same material and size, the sound wave can cause the temperatures of the first and second thermistor wires 20a and 20b to be different, thereby causing the actual resistance values (Ra-△R) and (Ra+△R) of the first and second thermistor wires 20a and 20b to be different. Therefore, when the sound wave is incident on the first or second thermistor wire 20a or 20b, the processor circuit 402 needs to add the actual resistance values (Ra-△R) and (Ra+△R) of the first and second thermistor wires 20a and 20b and calculate the average value as the resistance when calculating the resistance. Thus, the influence of the sound wave on the resistance of the first or second thermistor wire 20a or 20b can be eliminated.

[0149] Alternatively, when the sound wave causes the resistance values of the first and second thermistor wires 20a and 20b to change by a small △R, the change can be ignored. In this case, either of the actual resistance values (Ra-△R) and (Ra+△R) of the first and second thermistor wires 20a and 20b can be used as the resistance. Next, the following S102 can be performed to calculate the ambient temperature according to the obtained resistance and to provide the thermistor wire with a voltage matching the ambient temperature, so as to reduce the fluctuation of the performance of the microphone module 02 caused by the influence of the ambient temperature.

[0150] S102. According to the first signal, the voltage source is controlled to output a first voltage at a first ambient temperature and a second voltage at a second ambient temperature.

[0151] Specifically, Figure 13 The processor circuit 402 shown in the figure can perform the above S102 to output a voltage control instruction to the voltage control circuit 410a in the first control assembly 401a according to the first signal, i.e., the resistance of the first or second thermistor wire 20a or 20b, so that the first sub-voltage source 30a electrically connected to the voltage control circuit 410a outputs a first voltage U1 at a first ambient temperature T1 and a second voltage U2 at a second ambient temperature T2. At the same time, the processor circuit 402 outputs a voltage control instruction to the voltage control circuit 410b in the second control assembly 401b, so that the second sub-voltage source 30b electrically connected to the voltage control circuit 410b outputs a first voltage U1 at a first ambient temperature T1 and a second voltage U2 at a second ambient temperature T2.

[0152] Based on this, in the case that the materials and size specifications of the first thermistor wire 20a and the second thermistor wire 20b are the same, the first thermistor wire 20a and the second thermistor wire 20b receive the same temperature at the same ambient temperature. For example, when the first thermistor wire 20a and the second thermistor wire 20b both receive the first voltage U1 at the first ambient temperature T1, and the first thermistor wire 20a and the second thermistor wire 20b both receive the second voltage U2 at the second ambient temperature T2.

[0153] For example, in the case that the first ambient temperature T1 is higher than the second ambient temperature T2, the first voltage U1 can be greater than the second voltage U2. In this way, when the ambient temperature decreases from the first ambient temperature T1 to the second ambient temperature T2, the voltage applied to the first thermistor wire 20a and the second thermistor wire 20b can be reduced from the first voltage U1 to the second voltage U2. Alternatively, when the ambient temperature increases from the second ambient temperature T2 to the first ambient temperature T1, the voltage applied to the first thermistor wire 20a and the second thermistor wire 20b can be increased from the second voltage U2 to the first voltage U1. In this way, by adjusting the voltage applied to the first thermistor wire 20a and the second thermistor wire 20b, the fluctuation in the performance of the microphone module 02 caused by the influence of the ambient temperature can be reduced.

[0154] It should be noted that, in the case that the materials and size specifications of the first thermistor wire 20a, the second thermistor wire 20b, and the third thermistor wire 20c are the same, at the same ambient temperature, the voltage control circuit 410c in the third control assembly 401c can control the third sub-voltage source 30c to output the same voltage as the first sub-voltage source 30a and the second sub-voltage source 30b, so that at the same ambient temperature, the third thermistor wire 30c receives the same voltage as the first thermistor wire 20a and the second thermistor wire 20b.

[0155] In addition, the above is described by taking the example that the first thermistor wire 20a and the second thermistor wire 20b are respectively electrically connected to different control assemblies. Since in the case that the materials and size specifications of the first thermistor wire 20a and the second thermistor wire 20b are the same, the first thermistor wire 20a and the second thermistor wire 20b receive the same temperature at the same ambient temperature. Therefore, the voltage control circuit 410a in the first control assembly 401a to which the first thermistor wire 20a is electrically connected and the voltage control circuit 410b in the second control assembly 401b to which the second thermistor wire 20b is electrically connected can be shared. And the first sub-voltage source 30a and the second sub-voltage source 30b can also be shared.

[0156] As known from the above, the ambient temperature calculated by the processor circuit 402 in the microphone module 02 needs to match the voltage applied to the thermistor wire, such as the first thermistor wire 20a and the second thermistor wire 20b. Thus, the change of the external ambient temperature will not cause a large fluctuation in the performance of the microphone module 02. In this case, a data set composed of the voltage applied to the thermistor wire corresponding to each ambient temperature can be obtained under the condition that the performance of the microphone module 02, such as the sensitivity, the signal-to-noise ratio and the noise floor mentioned above, is unchanged, by means of simulation or experimental test, and the data set is stored in the memory 50.

[0157] In this way, when the processor circuit 402 in the microphone module 02 calculates the ambient temperature, the voltage matching the ambient temperature can be called from the memory 50, and the voltage source is controlled to provide the voltage to the thermistor wire, so as to reduce the fluctuation in the performance of the microphone module 02 caused by the influence of the ambient temperature. The data set is described in detail below.

[0158] For example, in some embodiments of the present application, the processor circuit 402 can store the first data set DS1 as shown in Table 2 and the second data set DS2 as shown in Table 3 in the memory 50 of the microphone module 02 before performing S102.

[0159] Table 2

[0160]

[0161] As can be seen from Table 2, the first data set DS1 can include a plurality of resistance value ranges, such as (R1-R2), (R2-R3), (R3-R4) and (R4-R5)…… and a plurality of ambient temperatures, such as Tes1, Tes2, Tes3 and Tes4…… One resistance value range matches one ambient temperature. For example, the resistance value range (R1-R2) matches the ambient temperature Tes1, the resistance value range (R2-R3) matches the ambient temperature Tes2, the resistance value range (R2-R3) matches the ambient temperature Tes3, and the resistance value range (R4-R5) matches the ambient temperature Tes4.

[0162] Table 3

[0163]

[0164] As can be seen from Table 3, the second data set DS2 includes a plurality of ambient temperature ranges, such as (Tes1-Tes2), (Tes2-Tes3), (Tes3-Tes4) and (Tes4-Tes5)…… and a plurality of voltages, such as Uol, Uo2, Uo3 and Uo4…… One ambient temperature range is matched with one voltage, such as the ambient temperature range (Tes1-Tes2) is matched with the voltage Uol, the ambient temperature range (Tes2-Tes3) is matched with the voltage Uo2, the ambient temperature range (Tes3-Tes4) is matched with the voltage Uo3, and the ambient temperature range (Tes4-Tes5) is matched with the voltage Uo4.

[0165] In this case, Figure 13 The processor circuit 402 shown in the above S102 can include, for example, as Figure 14 S201 and S202 shown.

[0166] S201, from the first data set DS1, according to the first signal, the resistance value range matched with the resistance of the thermistor.

[0167] Specifically, the processor circuit 402 can obtain the ambient temperature matched with the resistance value range where the resistance of the thermistor (e.g., the first thermistor wire 20a or the second thermistor wire 20b) is located from the first data set DS1 shown in Table 2 when performing S101. For example, when the above-mentioned resistance is located in the resistance value range (R1-R2), the processor circuit 402 can obtain the ambient temperature Tes1 matched with the resistance value range (R1-R2) as the first ambient temperature. Or, when the above-mentioned resistance is located in the resistance value range (R2-R3), the processor circuit 402 can obtain the ambient temperature Tes2 matched with the resistance value range (R2-R3) as the second ambient temperature.

[0168] It should be noted that the above-mentioned ambient temperature refers to the temperature of the surrounding air when the thermistor wire is working. However, after the thermistor wire is powered on, it will generate a certain temperature (which can be called working temperature) itself. The working temperature is related to the performance parameters of the thermistor wire, such as resistance. However, there is a certain temperature difference between the ambient temperature and the working temperature. Therefore, if the real-time resistance of the thermistor wire is directly used to call the voltage from the second data set DS2, the working temperature corresponding to the resistance will lead to inaccurate voltage calling, thereby affecting the stability of the performance of the microphone module 02.

[0169] Therefore, in order to improve the accuracy of the resistance obtained by the controller 40 in the microphone module 02, a data set of working temperatures corresponding to various environmental temperatures can be obtained by simulation or experimental testing, etc., under the condition that the performance of the microphone module 02, such as the sensitivity, signal-to-noise ratio, and background noise mentioned above, remains unchanged. The data set is stored in the memory 50.

[0170] In this way, the processor circuit 402 can obtain a working temperature matching the calculated real-time resistance, and further obtain an environmental temperature matching the working temperature from the working temperature, which is closer to the actual temperature of the environment in which the thermistor wire is actually located. Next, the calling voltage in the second data set DS2 of the environmental temperature is used to improve the accuracy of the finally obtained voltage. The data sets of the thermistor wire resistance value, environmental temperature, and working temperature are described in detail below.

[0171] Specifically, the first data set DS1 can include a first sub-set DS1a as shown in Table 4 and a second sub-set DS1b as shown in Table 5.

[0172] Table 4

[0173]

[0174] As can be seen from Table 4, the first sub-set DS1a can include a plurality of resistance value ranges (R1-R2), (R2-R3), (R3-R4), and (R4-R5) and a plurality of working temperature ranges (Tw1-Tw2), (Tw2-Tw3), (Tw3-Tw4), and (Tw4-Tw5). One resistance value range matches one working temperature range, for example, the resistance value range (R1-R2) matches the working temperature range (Tw1-Tw2), the resistance value range (R2-R3) matches the working temperature range (Tw2-Tw3), the resistance value range (R3-R4) matches the working temperature range (Tw3-Tw4), and the resistance value range (R4-R5) matches the working temperature range (Tw4-Tw5).

[0175] Table 5

[0176]

[0177]

[0178] As can be seen from Table 5, the second subset DS1b includes a plurality of working temperature ranges (Tw1-Tw2), (Tw2-Tw3), (Tw3-Tw4) and (Tw4-Tw5)…… and a plurality of ambient temperatures, for example, Tes1, Tes2, Tes3 and Tes4…… One working temperature range is matched with one ambient temperature, for example, the temperature range (Tw1-Tw2) is matched with the ambient temperature Tes1, the temperature range (Tw2-Tw3) is matched with the ambient temperature Tes2, the temperature range (Tw3-Tw4) is matched with the ambient temperature Tes3, and the temperature range (Tw4-Tw5) is matched with the ambient temperature Tes4.

[0179] In this case, the processor circuit 402 in the controller 40 performing the above-mentioned S201 can include:

[0180] Firstly, the processor circuit 402 can obtain the working temperature matched with the resistance value range where the resistance is located from the first subset DS1a as shown in Table 4. For example, when the above-mentioned resistance is located in the resistance value range (R1-R2), the processor circuit 402 can obtain the working temperature range (Tw1-Tw2) matched with the resistance value range (R1-R2) as the first working temperature range. Or, when the above-mentioned resistance is located in the resistance value range (R2-R3), the processor circuit 402 can obtain the working temperature range (Tw2-Tw3) matched with the resistance value range (R2-R3) as the second working temperature range.

[0181] Next, the processor circuit 402 obtains the ambient temperature Tes1 matched with the first working temperature range (Tw1-Tw2) from the second subset DS1b as shown in Table 5 as the first ambient temperature, or obtains the second ambient temperature Tes1 matched with the second working temperature range (Tw2-Tw3) from the second subset DS1b.

[0182] As can be seen from the above, in the process of the processor circuit 402 in the controller 40 performing the above-mentioned S201, the ambient temperature matched with the resistance can be obtained from the first data set DS1 (including the first subset DS1a and the second subset DS1b) stored in the memory 50 through the collected resistance. Therefore, the accuracy of the resistance value will finally affect the accuracy of the obtained ambient temperature. Based on this, in order to improve the accuracy of the resistance obtained by the controller 40 in the microphone module 02, the controller 40 can be configured to perform the following steps S202-S204. Figure 15As shown, the microphone module 02 can further include a temperature detector 51. The temperature detector 51 is electrically connected to the controller 40, and is arranged near the second thermistor wire 20b (or the first thermistor wire 20a). The temperature detector 51 is configured to collect the temperature of the second thermistor wire 20b (or the first thermistor wire 20a), and transmit the collected signal to the processor circuit 402 in the controller 40. In some embodiments, the signal collected by the temperature detector 51 can be the first signal.

[0183] Based on this, after the processor circuit 402 in the controller 40 obtains the first working temperature range or the second working temperature range matching the resistance value range where the resistance is located from the first subset DS1a, before the processor circuit 402 obtains the first ambient temperature matching the first working temperature range from the second subset DS1b, or obtains the second ambient temperature matching the second working temperature range from the second subset, the processor circuit 402 is further configured to determine whether the temperature of the thermistor wire collected by the temperature detector 51 is within the first working temperature range or the second working temperature range.

[0184] In this case, the processor circuit 402 is configured to obtain the ambient temperature matching the working temperature range from the second subset DS1b, including:

[0185] If the temperature of the thermistor wire collected by the temperature detector 51 is within the working temperature range, the processor circuit 402 obtains the first ambient temperature matching the first working temperature range from the second subset DS1b, or obtains the second ambient temperature matching the second working temperature range from the second subset. Alternatively, if the temperature of the thermistor wire collected by the temperature detector 51 is outside the working temperature range, the processor circuit 402 obtains the resistance of the thermistor wire again.

[0186] In this way, after the processor circuit 402 obtains the working ambient temperature range from the memory 50 according to the obtained resistance, the processor circuit 402 can determine whether the temperature of the thermistor wire collected by the temperature detector 51 falls within the working ambient temperature range. If the temperature falls within the working ambient temperature range, it means that the resistance obtained by the processor circuit 402 is accurate, so that the processor circuit 402 can continue to obtain the ambient temperature matching the ambient temperature range according to the ambient temperature range.

[0187] In addition, if the temperature does not fall within the working ambient temperature range, it means that the resistance obtained by the processor circuit 402 is not accurate, and the processor circuit 402 needs to obtain the resistance of the thermistor wire again to improve the accuracy of obtaining the resistance. Next, after the processor circuit 402 obtains the ambient temperature from the resistance, the processor circuit 402 can perform the following S202 to obtain the voltage matching the ambient temperature.

[0188] It should be noted that the above is to determine whether the resistance of the thermistor wire calculated by the processor circuit 402 is accurate by determining whether the temperature of the thermistor wire collected by the temperature detector 51 is within the working temperature range in the controller 40. Next, the ambient temperature of the thermistor wire is obtained through the resistance of the thermistor wire, and the voltage matched with the ambient temperature is obtained in S202. In other embodiments of the present application, the processor circuit 402 can obtain the ambient temperature of the thermistor wire directly through the temperature of the thermistor wire collected by the temperature detector 51 without calculating the resistance of the thermistor wire, and the voltage matched with the ambient temperature is obtained in S202.

[0189] S202, from the second data set, obtain the voltage matched with the ambient temperature, and control the voltage source to output the voltage.

[0190] Specifically, in the process of S202 executed by the processor circuit 402 in the controller 40, the voltage Uo1 matched with the first ambient temperature range (Tes1-Tes2) is obtained from the second data set DS2 as shown in Table 3 as the first voltage, and the above voltage source, for example, the first sub-voltage source 30a, the second sub-voltage source 30b, and the third sub-voltage source 30c as shown in Table 3, is controlled to output the above voltage Uo1 to the first thermistor wire 20a, the second thermistor wire 20b, and the third thermistor wire 20c, respectively. Figure 13

[0191] Alternatively, in the process of S202 executed by the processor circuit 402 in the controller 40, the voltage Uo2 matched with the second ambient temperature range (Tes2-Tes1) is obtained from the second data set DS2 as shown in Table 3 as the second voltage, and the above voltage source, for example, the first sub-voltage source 30a, the second sub-voltage source 30b, and the third sub-voltage source 30c as shown in Table 3, is controlled to output the above voltage Uo2 to the first thermistor wire 20a, the second thermistor wire 20b, and the third thermistor wire 20c, respectively. Figure 13

[0192] ​​In this way, when the first ambient temperature T1 of the thermistor wire is located in the first ambient temperature range (Tes1-Tes2), the voltage received by the thermistor wire is the voltage Uol as the first voltage U1, and when the second ambient temperature T2 of the thermistor wire is located in the second ambient temperature range (Tes2-Tes3), the voltage received by the thermistor wire is the voltage Uol as the second voltage U2. As can be seen from the above, in the case where the first ambient temperature T1 is higher than the second ambient temperature T2, the first voltage U1 can be greater than the second voltage U2, so that by adjusting the voltage applied to the first thermistor wire 20a and the second thermistor wire 20b, the fluctuation of the performance of the microphone module 02 caused by the influence of the ambient temperature can be reduced.

[0193] On this basis, it can be seen from the above formula (1), formula (2) and formula (3) that the temperature change AT degree of the thermistor wire 20 is proportional to the thermal diffusion coefficient D of the medium. In addition, it can be seen from formula (5) that the greater the temperature change AT of the thermistor wire 20, the greater the voltage difference Au0 of the output ends of the first thermistor wire 20a and the second thermistor wire 20b. And the voltage difference Au0 is proportional to the sensitivity of the microphone module 02. Therefore, the higher the thermal diffusion coefficient D of the medium in which the microphone module 02 is located, i.e. the higher the ambient temperature, the higher the sensitivity of the microphone module 02. However, the temperature of the environment in which the microphone module 02 is located cannot be unlimitedly high, and when the ambient temperature is too high, the thermistor wire will be damaged, so that the microphone module 02 cannot work normally.

[0194] In order to solve the above problem, in some embodiments of the present application, in the case where the materials and size specifications of the first thermistor wire 20a, the second thermistor wire 20b and the third thermistor wire 20c are the same, in order to detect the working state of the first thermistor wire 20a, the second thermistor wire 20b and / or the third thermistor wire 20c, the processor circuit 402 can also calculate the resistance Rc of the third thermistor wire 20c according to the voltage output by the third sub-voltage source 30c and the current collected by the current collection circuit 420c in the third control component 401c. Since the resistance of the thermistor wire changes with the change of temperature, by obtaining the resistance Rc of the third thermistor wire 20c, the temperature of the above three thermistor wires can be obtained. When the temperature exceeds a temperature threshold, a warning signal such as a buzzer or a flashing light can be sent to remind the user that the temperature of the microphone module 02 is too high, and the microphone module 02 can be turned off or the high-performance mode can be switched to the power-saving mode.

[0195] Alternatively, in some other embodiments of this application, the voltage at the second end of the first thermistor wire 20a or the second thermistor wire 20b can be detected. When this voltage is too high, the temperatures of the first and second thermistor wires 20a and 20b are too high. At this point, the voltage applied to the third thermistor wire 20c can be stopped, and the third thermistor wire 20c no longer provides a temperature field to the first and second thermistor wires 20a and 20b, thereby reducing their temperatures. In this case, the microphone module 02 does not need to include a third control component 401c and a third voltage source 30c electrically connected to the third thermistor wire 20c. The third thermistor wire 20c can share a voltage source with the first or second thermistor wire 20a.

[0196] The following example illustrates how the application of voltage to a third thermistor wire 20c is controlled by detecting the voltage output of the first thermistor wire 20a or the second thermistor wire 20b. In some embodiments of this application, such as... Figure 16 As shown, the microphone module 02 may include a switch (taking a switching transistor M as an example), an inductor L, and a comparator 60. The switch can be connected in series with a third thermistor wire 20c, which serves as a heating element. The switch's selection terminal receives a control signal, and the switch selectively conducts based on the control signal. For example, when the switch is a switching transistor M, the first terminal k1 of the switching transistor M is electrically connected to the second terminal g2 of the third thermistor wire 20c, and the second terminal k2 of the switching transistor M is grounded. The first terminal l1 of the inductor L is electrically connected to the second terminal c2 of the second thermistor wire 20b (or, the second terminal b2 of the first thermistor wire 20a). The first terminal m1 of the capacitor C is electrically connected to the second terminal l2 of the inductor L, and the second terminal m2 of the capacitor C is grounded. The inductor L and the capacitor C can form a filter circuit for filtering the signal.

[0197] In addition, a first input end of the comparator 60 (for example, an end marked with "+") is electrically connected to the second end l2 of the inductor L. A second input end of the comparator 60 (for example, an end marked with "-") is configured to receive a reference voltage Vref. An output end of the comparator 60 is electrically connected to a gate of the switch tube M. The comparator 60 is configured to output a control signal to the gate of the switch tube M to control the switch tube M to be turned off if the voltage V0 of the first input end of the comparator 60 is greater than the reference voltage Vref, and output a control signal to the gate of the switch tube M to control the switch tube M to be turned on if the voltage of the first input end of the comparator 60 is less than the reference voltage Vref. In addition, the comparator 60 is also electrically connected to a first working voltage end VDD and a second working voltage end VSS. The first working voltage end VDD and the second working voltage end VSS have a voltage difference to drive the comparator 60 to work.

[0198] The switch tube M can be a field effect transistor (EFT), and the first pole k1 of the switch tube M can be a source, and the second pole k2 can be a drain, or the first pole k1 of the switch tube M can be a drain, and the second pole k2 can be a source. The switch tube M can be an N-type transistor or a P-type transistor.

[0199] Based on this, in an example, when the switch tube M is a P-type transistor, if the comparison result of the comparator 60 is V1>Vref, at this time, the voltage applied to the second thermistor wire 20b and the first thermistor wire 20a is large, and the temperature of the second thermistor wire 20b and the first thermistor wire 20a is too high. In order to avoid the failure of the second thermistor wire 20b and the first thermistor wire 20a, the comparator 60 can output a high level, and at this time, the switch tube M is turned off. At this time, the third thermistor wire 20c is in a disconnected state with the ground end GND, and no current flows through the third thermistor wire 20c, so that the third thermistor wire 20c no longer provides a temperature field to the first thermistor wire 20a and the second thermistor wire 20b, thereby achieving the purpose of reducing the temperature of the first thermistor wire 20a and the second thermistor wire 20b.

[0200] Or, when the comparison result of the comparator 60 is V1 < Vref, the voltage applied to the second thermistor wire 20b and the first thermistor wire 20a is smaller, and the temperature of the second thermistor wire 20b and the first thermistor wire 20a does not cause the second thermistor wire 20b and the first thermistor wire 20a to fail. The comparator 60 can output a low level, and at this time the switch tube M is turned on. At this time, the third thermistor wire 20c is in an electrically connected state with the ground terminal GND, and the current flows through the third thermistor wire 20c, so that the third thermistor wire 20c provides a temperature field to the first thermistor wire 20a and the second thermistor wire 20b to improve the sensitivity of the microphone module 02.

[0201] Or, for example, in the case of an N-type transistor, when the comparison result of the comparator 60 is V1 > Vref, the voltage applied to the second thermistor wire 20b and the first thermistor wire 20a is larger, and the temperature of the second thermistor wire 20b and the first thermistor wire 20a is too high. In order to avoid the failure of the second thermistor wire 20b and the first thermistor wire 20a, the comparator 60 can output a low level, and at this time the switch tube M is turned off. Or, when the comparison result of the comparator 60 is V1 < Vref, the voltage applied to the second thermistor wire 20b and the first thermistor wire 20a is smaller, and the temperature of the second thermistor wire 20b and the first thermistor wire 20a does not cause the second thermistor wire 20b and the first thermistor wire 20a to fail. The comparator 60 can output a high level, and at this time the switch tube M is turned on.

[0202] On this basis, from the above, Figure 16 Among them, the resistance change of the first thermistor wire 20a and the second thermistor wire 20b can be converted into a voltage difference △u0. By signal processing the voltage difference △u0, sound information can be obtained. Specifically, as shown in Figure 17 The microphone module 02 can also include an operational amplifier 61. The first input end (for example, the end marked "+") of the operational amplifier 61 is electrically connected to the second end b2 of the first thermistor wire 20a, and the second input end (for example, the end marked "-") of the operational amplifier 61 is electrically connected to the second end c2 of the second thermistor wire 20b. The operational amplifier 61 is used to amplify the voltage difference △u0.

[0203] In addition, the microphone module 02 can also include, for example, Figure 18The diagram shows a noise reduction circuit 62, an analog-to-digital converter (ADC) 63, and a digital signal processor 64. The noise reduction circuit 62 is electrically connected between the second end b2 of the first thermistor wire 20a and the first input terminal of the operational amplifier 61. The noise reduction circuit 62 is also electrically connected between the second end c1 of the second thermistor wire 20b and the second input terminal of the operational amplifier. This noise reduction circuit 62 is used to reduce the noise of the voltage difference Δu0. In some embodiments, the noise reduction circuit 62 may include multiple stages of sub-noise reduction circuits, which can reduce noise step by step to improve the noise reduction effect.

[0204] Furthermore, the input terminal of the analog-to-digital converter 63 is electrically connected to the output terminal of the operational amplifier 61, and the analog-to-digital converter 63 is used to convert the analog signal output by the operational amplifier 61 into a digital signal. The input terminal of the digital signal processor 64 is electrically connected to the output terminal of the analog-to-digital converter 63. The digital signal processor 64 is used to perform at least one of the following on the digital signal output by the analog-to-digital converter 63: noise reduction processing, reverberation cancellation processing (e.g., eliminating ambient reverberation), or echo cancellation processing.

[0205] The above describes how the controller 40 in the microphone module 02 controls the voltage source to output different voltages based on the varying ambient temperatures of the thermistor wire, thereby reducing performance fluctuations caused by ambient temperature. Other embodiments of the microphone module 02 provided in this application include... Figure 19 As shown, the device may include a controller 40, a voltage converter 70, and at least two of the aforementioned heating elements and at least one thermistor. For example, the heating element may be a first thermistor wire 20a, and the thermistor may be a second thermistor wire 20b. The controller 40 may be electrically connected to the voltage converter 70. The voltage converter 70 has a voltage terminal 701, which is electrically connected to the aforementioned first thermistor wire 20a and second thermistor wire 20b.

[0206] In this case, the voltage converter 70 is used to output different voltages according to the aforementioned first signal. For example, under the control of the aforementioned controller 40, the voltage converter 70 can output a first voltage U1 at a first ambient temperature T1 and a second voltage U2 at a second ambient temperature T2, according to the aforementioned first signal. Based on this, the first thermistor wire 20a and the second thermistor wire 20b are used to receive the acoustic wave signal and the electrical signal output from the voltage terminal 701 of the voltage converter 70, and the resistance values ​​of the first thermistor wire 20a and the second thermistor wire 20b are used to change under the action of the acoustic wave signal.

[0207] The voltage converter 70 can be a DC voltage conversion circuit, such as a low dropout regulator (LDO), a buck circuit, a boost circuit, or a buck-boost circuit. In some embodiments of the present application, the voltage converter 70 can be part of, or be, the voltage source 30. Alternatively, in some other embodiments of the present application, the voltage source 30 can be part of, or be, the voltage converter 70.

[0208] Accordingly, the controller 40 can obtain the resistance of the thermistor wire, and according to the resistance, retrieve a voltage corresponding to the real-time resistance from the memory 50. The process of retrieving the voltage by the controller 40 is as described above, and will not be repeated here. Next, the controller 40 can control the voltage converter 70 to output a voltage in a ratio of the input voltage, so that the voltage converter 70 can output the voltage retrieved by the controller 40 to the first thermistor wire 20a and the second thermistor wire 20b. The technical effects of the microphone module 02 with the voltage converter 70 are as described above, and will not be repeated here.

[0209] In addition, in order to process the voltage difference Δu0 between the second end of the first thermistor wire 20a and the second end of the second thermistor wire 20b to obtain sound information. The microphone module 02 with the voltage converter 70 can also include an operational amplifier, at least one level of noise reduction circuit, an analog-to-digital converter, and a digital signal processor. The connection relationship and functions of the operational amplifier, the noise reduction circuit, the analog-to-digital converter, and the digital signal processor are as described above, and will not be repeated here.

[0210] It should be noted that the above is an example of a microphone module 02 including two thermistor wires, such as the first thermistor wire 20a and the second thermistor wire 20b. In some other embodiments of the present application, the microphone module 02 can also include the third thermistor wire 20c. The technical effects of the third thermistor wire 20c are as described above, and will not be repeated here.

[0211] It should be noted that the above is an example of when the voltage applied to the second thermistor wire 20b and the first thermistor wire 20a is large, the temperature of the second thermistor wire 20b and the first thermistor wire 20a is too high, and in order to avoid the failure of the second thermistor wire 20b and the first thermistor wire 20a, the third thermistor wire 20c as a heating element is further provided with a temperature field.

[0212] In some embodiments of the present application, when the switch tube M is an N-type transistor, in order to avoid the second thermistor 20b and the first thermistor 20a from being damaged due to over high temperature, when the comparison result of the comparator 60 is that V1 is less than, but close to the reference voltage Vref, the switch tube M can be controlled to be turned on, and the voltage applied to the third thermistor 20c is reduced, so as to reduce the heat of the third thermistor 20c, and thus the second thermistor 20b and the first thermistor 20a receive less heat from the third thermistor 20c. Alternatively, in some embodiments of the present application, when the second thermistor 20b and the first thermistor 20a are at a lower temperature, i.e., the comparison result of the comparator 60 is that V1 is much less than the reference voltage Vref, the switch tube M can be controlled to be turned on, and the voltage applied to the third thermistor 20c is increased, so as to increase the heat of the third thermistor 20c, and thus the second thermistor 20b and the first thermistor 20a receive more heat from the third thermistor 20c. In addition, in some embodiments of the present application, when the fluid detection device 01, such as the microphone module 02, is a two-wire model (i.e., including the first thermistor 20a and the second thermistor 20b), or a three-wire model (i.e., including the first thermistor 20a, the second thermistor 20b, and the third thermistor 20c), when the ambient temperature of the fluid detection device 01 changes, a fixed voltage can be provided to the first thermistor 20a and the second thermistor 20b. In addition, according to the change of the temperature of the first thermistor 20a and the second thermistor 20b, the switch tube M is controlled to be turned off or turned on, or when the switch tube M is turned on, the voltage applied to the third thermistor 20c is controlled, for the purpose of adjusting the temperature of the second thermistor 20b and the first thermistor 20a. The specific adjustment process is as described above, and will not be described here again.

[0213] In addition, an embodiment of the present application provides a computer readable storage medium. The computer readable medium includes computer instructions, when the computer instructions run on the controller 40, make the controller 40 execute any one of the control methods as described above. The technical effect of the computer readable storage medium is as described above, and will not be described here again.

[0214] An embodiment of the present application also provides a computer program product. The computer program product includes computer instructions, when the computer instructions run on the controller 40, make the controller 40 execute any one of the control methods as described above. The technical effect of the computer program product is as described above, and will not be described here again.

[0215] In the above embodiments, all or part of the embodiments can be implemented by software, hardware, firmware or any combination thereof. When implemented by using a software program, all or part of the embodiments can be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions according to the embodiments of the present application are generated. The computer can be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. The computer instructions can be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions can be transmitted from one website site, computer, server or data center to another website site, computer, server or data center through a wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) manner. The computer readable storage medium can be any available medium that can be accessed by a computer or data storage device including one or more servers, data centers, etc. integrated with the medium. The available medium can be a magnetic medium (such as a floppy disk, a hard disk, a magnetic tape), an optical medium (such as a DVD), or a semiconductor medium (such as a solid state disk (SSD)), etc.

[0216] The above description is merely a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A fluid detection device, characterized by, The fluid detection device comprises: a voltage source; a channel for fluid flow; at least one heating element electrically connected to the voltage source; at least one thermistor electrically connected to the voltage source, the at least one thermistor being used to sense the ambient temperature of the at least one thermistor; wherein the fluid flows through the thermistor when the fluid flows in the channel; the fluid detection device is a microphone module, and the fluid is a gas; when the ambient temperature of the at least one thermistor is a first ambient temperature, the voltage source outputs at least a first voltage to the at least one thermistor, and when the ambient temperature of the at least one thermistor is a second ambient temperature, the voltage source outputs at least a second voltage to the at least one thermistor; wherein the first ambient temperature and the second ambient temperature are different, and the first voltage and the second voltage are different. The fluid detection device further comprises: a substrate comprising a groove, the heating element and the thermistor being respectively arranged on two sides of the groove; the groove is the channel, or the groove is a part of the channel; the groove serves as a channel for propagating sound waves.

2. The fluid detection device according to claim 1, wherein: the first ambient temperature is higher than the second ambient temperature; the first voltage is greater than the second voltage.

3. The fluid detection device of claim 1 or 2, wherein, The fluid detection device further comprises: a controller electrically connected to the voltage source; wherein the thermistor is used to generate a first signal corresponding to the temperature of the thermistor; and the controller is configured to output a voltage control signal to the voltage source according to the first signal.

4. The fluid detection device according to claim 3, wherein: the controller comprises: a processor circuit configured to output a voltage control instruction according to the first signal; at least one control component; the control component comprises: a voltage control circuit electrically connected to the voltage source and the processor circuit, the voltage control circuit being configured to output the voltage control signal to the voltage source according to the voltage control instruction.

5. The fluid detection device of claim 4, wherein, The control component further comprises: a current acquisition circuit electrically connected to the voltage source and the processor circuit, the current acquisition circuit being configured to acquire a current flowing through the thermistor and output a current signal to the processor circuit, and the first signal comprises the current signal.

6. The fluid detection device according to claim 4, wherein: the processor circuit is further configured to receive a first mode selection operation of a user and output the voltage control instruction to the voltage control circuit in response to the first mode selection operation, so that the voltage source outputs a first mode initial voltage; or, the processor circuit is further configured to receive a second mode selection operation of a user and output the voltage control instruction to the voltage control circuit in response to the second mode selection operation, so that the voltage source outputs a second mode initial voltage; wherein the first mode initial voltage is less than the second mode initial voltage.

7. The fluid detection device of claim 6, wherein, the first mode initial voltage is 2 V ~ 4 V; the second mode initial voltage is 5 V ~ 12 V.

8. The fluid detection device of claim 1 or 2, wherein, the at least one thermistor comprises a first thermistor and a second thermistor; the first thermistor and the second thermistor are respectively as two branches of a bridge circuit.

9. The fluid detection device of claim 8, wherein, The fluid detection device further comprises: a first resistor, the first resistor is connected in series between the voltage source and the ground terminal with the first thermistor; a second resistor, the second resistor is connected in series between the voltage source and the ground terminal with the second thermistor; an operational amplifier, a first input terminal of the operational amplifier is electrically connected between the first resistor and the first thermistor, a second input terminal of the operational amplifier is electrically connected between the second resistor and the second thermistor.

10. The fluid detection device of claim 8, wherein, The fluid detection device further comprises: a comparator, a first input terminal of the comparator is electrically connected to an end of the first thermistor or the second thermistor away from the voltage source, a second input terminal of the comparator is used to receive a reference voltage, and an output terminal of the comparator outputs a control signal; a switch, the switch is connected in series with the at least one heating element, a gate terminal of the switch receives the control signal, and the switch is selectively turned on based on the control signal.

11. The fluid detection device of claim 9, wherein, The fluid detection device further comprises: a noise reduction circuit, the noise reduction circuit is electrically connected between the first thermistor and the first input terminal of the operational amplifier, and the noise reduction circuit is also electrically connected between the second thermistor and the second input terminal of the operational amplifier; an analog-to-digital converter, an input terminal of the analog-to-digital converter is electrically connected with an output terminal of the operational amplifier, used to convert an analog signal output by the operational amplifier into a digital signal; a digital signal processor, an input terminal of the digital signal processor is electrically connected with an output terminal of the analog-to-digital converter, used to perform at least one of noise reduction processing, reverberation elimination processing and echo elimination processing on the digital signal output by the analog-to-digital converter.

12. The fluid detection device of claim 4, wherein, the at least one thermistor comprises a first thermistor and a second thermistor; the first thermistor and the second thermistor are respectively as two branches of a bridge circuit; the voltage source comprises a first sub-voltage source, a second sub-voltage source and a third sub-voltage source; wherein the first thermistor is electrically connected with the first sub-voltage source, the second thermistor is electrically connected with the second sub-voltage source, and the at least one heating element is electrically connected with the third sub-voltage source; the controller comprises three control components, which are respectively a first control component, a second control component and a third control component; the first control component is electrically connected with the first sub-voltage source; the second control component is electrically connected with the second sub-voltage source; the third control component is electrically connected with the third sub-voltage source.

13. The fluid detection device of claim 3, wherein, The fluid detection device further comprises: A temperature detector is electrically connected to the controller, and the thermistor is configured to collect the temperature of the thermistor and transmit the collection result to the controller.

14. The fluid detection device of claim 3, wherein, The first signal is used to characterize the resistance of the thermistor.

15. The fluid detection device of claim 1 or 2, wherein, When the ambient temperature of the thermistor is a third ambient temperature, the voltage source outputs a third voltage to the at least one heating element, and when the ambient temperature of the thermistor is a fourth ambient temperature, the voltage source outputs a fourth voltage to the at least one heating element. Wherein, the third ambient temperature and the fourth ambient temperature are different, and the third voltage and the fourth voltage are different.

16. The fluid detection device according to claim 15, wherein The third ambient temperature is lower than the fourth ambient temperature. The third voltage is greater than the fourth voltage.

17. The fluid detection device of claim 1 or 2, wherein, The thermistor is also used to sense the flow of the fluid.

18. A control method characterized by, The control method is applied to a controller in a fluid detection device, and the fluid detection device further comprises a voltage source, a channel for fluid flow, at least one heating element, and at least one thermistor; the at least one heating element is electrically connected to the voltage source, and the at least one thermistor is electrically connected to the voltage source; wherein, when the fluid flows in the channel, the fluid flows through the at least one thermistor; the fluid detection device is a microphone module, and the fluid is a gas; the fluid detection device further comprises a substrate; the substrate comprises a groove, and the heating element and the thermistor are respectively arranged on both sides of the groove; the groove is the channel, or the groove is part of the channel; the groove serves as a channel for propagating sound waves; The method comprises: The controller receives a first signal generated by the at least one thermistor corresponding to the temperature of the at least one thermistor; When the ambient temperature of the at least one thermistor is a first ambient temperature, the controller controls the voltage source to output at least a first voltage to the at least one thermistor according to the first signal, and when the ambient temperature of the at least one thermistor is a second ambient temperature, the controller controls the voltage source to output at least a second voltage to the at least one thermistor according to the first signal; Wherein, the first ambient temperature and the second ambient temperature are different, and the first voltage and the second voltage are different.

19. The control method according to claim 18, wherein The first ambient temperature is higher than the second ambient temperature. The first voltage is greater than the second voltage.

20. The control method according to claim 18 or 19, wherein Before the controller acquires the first signal, the method further comprises: Receiving a first mode selection operation of a user; In response to the first mode selection operation, the controller controls the voltage source to output the first mode initial voltage; Or, Before acquiring the first signal, the method further comprises: Receiving a second mode selection operation of a user; In response to the second mode selection operation, the controller controls the voltage source to output the second mode initial voltage.

21. The control method of claim 20, wherein, the first mode initial voltage is 2 V ~ 4 V; the second mode initial voltage is 5 V ~ 12 V.

22. The control method according to claim 18, wherein the first signal is used to represent the resistance of the thermistor.

23. The control method of claim 22, wherein, the step of controlling the voltage source to output at least a first voltage to the thermistor according to the first signal when the thermistor is at a first ambient temperature, and to output at least a second voltage to the thermistor according to the first signal when the thermistor is at a second ambient temperature, comprises: obtaining the first ambient temperature or the second ambient temperature matching the resistance range of the thermistor from a first data set according to the first signal, wherein the first data set comprises a plurality of resistance ranges and a plurality of ambient temperatures, and one resistance range matches one ambient temperature; obtaining the first voltage matching the ambient temperature range of the first ambient temperature from a second data set, and controlling the voltage source to output the first voltage, or obtaining the second voltage matching the ambient temperature range of the second ambient temperature from the second data set, and controlling the voltage source to output the second voltage, wherein the second data set comprises a plurality of ambient temperature ranges and a plurality of voltages, and one ambient temperature range matches one voltage.

24. The control method of claim 23, wherein, the first data set comprises a first sub-set and a second sub-set, the first sub-set comprises a plurality of resistance ranges and a plurality of working temperature ranges, and one resistance range matches one working temperature range, and the second sub-set comprises a plurality of working temperature ranges and a plurality of ambient temperatures, and one working temperature range matches one ambient temperature; the step of obtaining the first ambient temperature or the second ambient temperature matching the resistance of the thermistor from the first data set according to the first signal comprises: obtaining a first working temperature range or a second working temperature range matching the resistance range of the thermistor from the first sub-set, and obtaining the first ambient temperature matching the first working temperature range from the second sub-set, or obtaining the second ambient temperature matching the second working temperature range from the second sub-set.

25. A computer-readable storage medium, characterized in that, a computer program product comprising computer instructions which, when executed on a controller, cause the controller to perform the control method of any one of claims 18-24.

26. A computer program product, characterised in that, a computer program product comprising computer instructions which, when executed on a controller, cause the controller to perform the control method of any one of claims 18-24.

27. A fluid detection device, comprising: comprises: a channel for fluid flow; the fluid detection device is a microphone module, and the fluid is gas; at least one heating element; at least one thermistor for generating a first signal corresponding to a temperature of the at least one thermistor; wherein the fluid flows through the at least one thermistor when the fluid flows in the channel; a voltage converter having a voltage terminal electrically connected with the at least one heating element and the at least one thermistor, the voltage converter being configured to output a supply voltage from the voltage terminal to the at least one thermistor according to the first signal; wherein the supply voltage outputted from the voltage terminal is a first voltage when the temperature of the at least one thermistor is a first temperature, and the supply voltage outputted from the voltage terminal is a second voltage when the temperature of the at least one thermistor is a second temperature; the fluid detection device further comprises: a substrate comprising a groove, the heating element and the thermistor are respectively arranged on two sides of the groove; the groove is the channel, or the groove is a part of the channel; the groove serves as a channel for propagating acoustic waves.

28. An electronic device, comprising: a fluid detection device as claimed in any one of claims 1-17, or a fluid detection device as claimed in claim 27; the fluid detection device is arranged in a housing.

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