Acquisition circuit, control method and equipment of temperature sensor

Abstract

The invention discloses an acquisition circuit, a control method and equipment of a temperature sensor. The acquisition circuit of the temperature sensor comprises a switch module and at least one temperature sensor, wherein the switch module is connected between a power supply end and the temperature sensor; the sampling module is connected with the temperature sensor and is used for collecting the voltage of the temperature sensor and generating a first electric signal; and the processing module is connected with the sampling module and the switch module, is used for generating a current temperature value according to the first electric signal, and is also used for controlling the conduction frequency of the switch module when the acquisition circuit runs for a long time. According to the technical scheme provided by the embodiment of the invention, the detection precision of the temperature sensor during long-time operation is improved.

Description

Technical Field

[0001] This invention relates to the field of temperature detection technology, and in particular to a temperature sensor acquisition circuit, control method, and device. Background Technology

[0002] The resistance value of a temperature sensor can change according to different temperatures, and this change is highly accurate in terms of tracking and repeatability. Therefore, the current temperature can be detected by measuring the resistance value of the temperature sensor. However, as the temperature sensor operates for a long time, it will heat up or age, which will affect the correspondence between the resistance value of the temperature sensor and the temperature, causing errors in temperature detection. Summary of the Invention

[0003] This invention provides a temperature sensor acquisition circuit, control method, and device to solve the problem of low temperature detection accuracy when the temperature sensor is running for a long time.

[0004] According to one aspect of the present invention, a temperature sensor acquisition circuit is provided, comprising:

[0005] A switching module and at least one temperature sensor, wherein the switching module is connected between a power supply terminal and the temperature sensor;

[0006] A sampling module, connected to the temperature sensor, is used to acquire the voltage of the temperature sensor and generate a first electrical signal;

[0007] The processing module, connected to the sampling module and the switching module, is used to generate the current temperature value based on the first electrical signal, and also to control the conduction frequency of the switching module when the acquisition circuit is running for a long time.

[0008] Optionally, the switching module includes: an opto-isolating switch, a field-effect transistor switching switch, and a transistor digitally controlled switch.

[0009] Optionally, the temperature sensor includes at least two, and each of the temperature sensors is connected in series.

[0010] Optionally, the temperature sensor's acquisition circuit further includes:

[0011] A current-limiting resistor is connected between the switching module and the temperature sensor.

[0012] Optionally, the conduction frequency of the switching module is inversely proportional to the operating time of the acquisition circuit.

[0013] Optionally, the temperature sensor is a thermistor-type temperature sensor.

[0014] According to another aspect of the present invention, a control method for a temperature sensor acquisition circuit is provided, characterized in that it is applied to the temperature sensor acquisition circuit described in any embodiment of the present invention;

[0015] The control method for the acquisition circuit of the temperature sensor includes:

[0016] The processing module controls the switching module to operate at a first conduction frequency;

[0017] When the switch module is turned on, the sampling module acquires the voltage of the temperature sensor and generates the first electrical signal;

[0018] The processing module generates the current temperature value based on the first electrical signal.

[0019] Optionally, after the processing module generates the current temperature value based on the first electrical signal, it includes:

[0020] The processing module fits a temperature change curve based on the current temperature value at different times.

[0021] According to another aspect of the present invention, a temperature sensing device is provided, comprising: a data acquisition circuit of the temperature sensor described in any embodiment of the present invention.

[0022] The technical solution provided in this invention, by incorporating a switching module, allows the temperature sensor to operate intermittently. This prevents heat accumulation due to prolonged energization, improving the testing accuracy of the temperature sensor during extended use. Furthermore, the low heat accumulation reduces the aging time of the temperature sensor, thereby extending its lifespan.

[0023] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the acquisition circuit of a temperature sensor according to an embodiment of the present invention;

[0026] Figure 2This is a schematic diagram of the acquisition circuit of another temperature sensor provided according to an embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of the acquisition circuit of another temperature sensor according to an embodiment of the present invention;

[0028] Figure 4 This is a flowchart of a control method for a temperature sensor acquisition circuit according to an embodiment of the present invention;

[0029] Figure 5 This is a flowchart of a control method for a temperature sensor acquisition circuit according to an embodiment of the present invention. Detailed Implementation

[0030] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0031] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0032] This invention provides a temperature sensor acquisition circuit. Figure 1 This is a schematic diagram of the acquisition circuit of a temperature sensor provided in an embodiment of the present invention. (Reference) Figure 1The temperature sensor's acquisition circuit includes: a switching module 2, a sampling module 3, a processing module 4, and at least one temperature sensor 1. The switching module 2 is connected between the power supply terminal VDD and the temperature sensor 1. The sampling module 3 is connected to the temperature sensor 1 and is used to acquire the voltage of the temperature sensor 1 and generate a first electrical signal. The processing module 4 is connected to the sampling module 3 and the switching module 2, and is used to generate the current temperature value based on the first electrical signal. It is also used to control the conduction frequency of the switching module 2 during long-term operation of the acquisition circuit.

[0033] Temperature sensor 1 reacts to temperature changes by changing its own resistance. When the current from the power supply terminal VDD is transmitted to temperature sensor 1 through the switch module 2, temperature sensor 1 will generate different voltage values ​​according to different resistance values. Since the magnitude of the output current from the power supply terminal VDD is controllable, temperature can be detected by detecting the voltage of temperature sensor 1.

[0034] Optionally, temperature sensor 1 is a thermistor-type temperature sensor. With long-term use, the electrothermal phenomenon of temperature sensor 1 will inevitably affect its detection results, and the heating will also lead to rapid aging of temperature sensor 1. All of these can cause inaccurate detection, and this deviation will become more and more obvious over time.

[0035] If the heating phenomenon of temperature sensor 1 can be reduced by reducing the output current of power supply VDD and using a very small current, the voltage of temperature sensor 1 will also be very small. Therefore, a more precise and sensitive sampling module 3 is required, and an operational amplifier unit is also needed, which has a higher cost. In addition, the small current also has a lower anti-interference capability and is also prone to causing the voltage of temperature sensor 1 to deviate.

[0036] Therefore, by adding a switch module 2 and controlling its conduction frequency, this invention allows the temperature sensor 1 to be powered on in a time-division multiplexing manner, essentially making its operation a point-based, time-based process. For example, the switch module 2 can be turned on once every 10ms, allowing for the acquisition of its voltage 100 times within one second. The sampling module 3 generates 100 first electrical signals based on these 100 voltage acquisitions, and the processing module 4 generates the current temperature value based on each of these first electrical signals. Because temperature change is a continuous process, high accuracy can still be maintained through time-division multiplexing of temperature detection.

[0037] Because the operating time of temperature sensor 1 is dispersed and short, the probability of external electrical interference to the operating temperature sensor 1 and its circuit is reduced. Simultaneously, it avoids the accumulation of heat in temperature sensor 1. Therefore, this invention can also appropriately increase the output current of the power supply terminal VDD, thereby improving the ability of the acquisition circuit to resist low-power external electrical interference without causing overheating of temperature sensor 1.

[0038] The technical solution provided in this invention, by incorporating a switching module, allows the temperature sensor to operate intermittently. This prevents heat accumulation due to prolonged energization, improving the testing accuracy of the temperature sensor during extended use. Furthermore, the low heat accumulation reduces the aging time of the temperature sensor, thereby extending its lifespan.

[0039] Figure 2 This is a schematic diagram of the acquisition circuit for another temperature sensor provided in an embodiment of the present invention. (Refer to...) Figure 2 Based on the above embodiments, the switch module 2 may optionally include: an opto-isolation switch, a field-effect transistor switching switch, and a transistor digital control switch.

[0040] in, Figure 2 An example of a switching module 2 for an opto-isolating switch is shown. The opto-isolating switch can be controlled by a processing module 4, and the switching on and off of the opto-isolating switch is driven according to the control signal of the processing module 4, so that the temperature sensor 1 operates in a controllable alternating on and off state.

[0041] For example, the switch module 2 is not limited to opto-isolation switches, field-effect transistor switching switches and transistor digital control switches. In other embodiments, other switch types can also be used, as long as the power-on method that can ensure the alternating on and off of the temperature sensor is maintained.

[0042] Based on the above embodiments, optionally, the temperature sensor includes at least two temperature sensors connected in series.

[0043] By setting up multiple temperature sensors, the total series voltage of the temperature sensors connected in series is increased. By acquiring a higher voltage value through the sampling module, the sensitivity of the selected devices in the subsequent sampling and processing modules can be reduced, thereby reducing the design difficulty of the acquisition circuit and the device cost of the sampling and processing modules.

[0044] Figure 3 This is a schematic diagram of the acquisition circuit for another temperature sensor provided in an embodiment of the present invention. (Reference) Figure 3 Based on the above embodiments, optionally, the temperature sensor acquisition circuit further includes a current-limiting resistor R, connected between the switch module 2 and the temperature sensor 1.

[0045] By setting a current-limiting resistor R, the excessive current can be prevented from impacting the temperature sensor 1, thereby improving the service life of the temperature sensor 1.

[0046] Based on the above embodiments, optionally, the conduction frequency of the switching module is inversely proportional to the running time of the acquisition circuit.

[0047] When the operating time of the acquisition circuit is short, the temperature sensor will not generate significant heat. In this case, the conduction frequency of the switching module can be increased, so that the temperature sensor has a longer power-on time per unit time, thereby improving the detection accuracy of the temperature sensor.

[0048] As the operating time of the acquisition circuit continues to increase, in order to reduce the heat generation of the temperature sensor, the conduction frequency of the switching module can be reduced, thereby reducing the power-on time of the temperature sensor per unit time.

[0049] By changing the conduction frequency of the switching module, the operation of the temperature sensor's acquisition circuit becomes more flexible, ensuring the detection accuracy of the temperature sensor while reducing its heat generation.

[0050] This invention also provides a control method for the acquisition circuit of a temperature sensor. This method is applied to the acquisition circuit of the temperature sensor provided in any embodiment of this invention. Figure 4 This is a flowchart illustrating a control method for a temperature sensor acquisition circuit provided in an embodiment of the present invention. (See reference) Figure 4 The control methods for the temperature sensor's acquisition circuit include:

[0051] S110, The processing module controls the switch module to operate at the first conduction frequency.

[0052] S120: When the switching module is turned on, the sampling module collects the voltage of the temperature sensor and generates the first electrical signal.

[0053] S130, The processing module generates the current temperature value based on the first electrical signal.

[0054] In the various embodiments of the temperature sensor acquisition circuit, the specific descriptions of the control methods for different temperature sensor acquisition circuits are provided. These control methods can all be considered as the control methods for the temperature sensor acquisition circuit provided in the embodiments of the present invention, and repeated content will not be described here.

[0055] Figure 5 A flowchart illustrating a control method for a temperature sensor acquisition circuit provided in an embodiment of the present invention. (See reference...) Figure 5 Based on the above embodiments, optionally, after the processing module generates the current temperature value according to the first electrical signal in S130, the following steps are included:

[0056] S140 The processing module fits the temperature change curve based on the current temperature value at different times.

[0057] In actual environments such as industrial measurement and control, temperature parameters do not change particularly rapidly or abruptly. Therefore, a complete temperature change curve can be fitted using a relatively low-frequency point-to-time sampling measurement method. The fitted temperature change curve can effectively and continuously detect the temperature parameter changes at each specific point.

[0058] Therefore, this invention does not require the continuous operation of the temperature sensor as in existing solutions, but instead adopts a time-segmented operation mode, which effectively reduces the heat generation of the temperature sensor and ensures the detection accuracy of the temperature sensor, thus achieving better results.

[0059] This invention also provides a temperature sensing device, which includes: the acquisition circuit of the temperature sensor provided in any embodiment of this invention, which has similar beneficial effects to the acquisition circuit of the temperature sensor, and will not be described in detail here.

[0060] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0061] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A temperature sensor acquisition circuit, characterized in that, include: A switching module and at least one temperature sensor, wherein the switching module is connected between a power supply terminal and the temperature sensor; A sampling module, connected to the temperature sensor, is used to acquire the voltage of the temperature sensor and generate a first electrical signal; The processing module, connected to the sampling module and the switching module, is used to generate the current temperature value based on the first electrical signal, and also to control the conduction frequency of the switching module when the acquisition circuit is running for a long time.

2. The temperature sensor acquisition circuit according to claim 1, characterized in that, The switching module includes: an opto-isolating switch, a field-effect transistor switching switch, and a transistor digital control switch.

3. The temperature sensor acquisition circuit according to claim 1, characterized in that, The temperature sensor includes at least two, and each of the temperature sensors is connected in series.

4. The acquisition circuit of the temperature sensor according to claim 1, characterized in that, The temperature sensor's data acquisition circuit also includes: A current-limiting resistor is connected between the switching module and the temperature sensor.

5. The acquisition circuit of the temperature sensor according to claim 1, characterized in that, The conduction frequency of the switching module is inversely proportional to the operating time of the acquisition circuit.

6. The acquisition circuit of the temperature sensor according to claim 1, characterized in that, The temperature sensor is a thermistor type temperature sensor.

7. A control method for a temperature sensor acquisition circuit, characterized in that, The acquisition circuit is applied to the temperature sensor according to any one of claims 1-6; The control method for the acquisition circuit of the temperature sensor includes: The processing module controls the switching module to operate at a first conduction frequency; When the switch module is turned on, the sampling module acquires the voltage of the temperature sensor and generates the first electrical signal; The processing module generates the current temperature value based on the first electrical signal.

8. The control method for the acquisition circuit of the temperature sensor according to claim 7, characterized in that, After the processing module generates the current temperature value based on the first electrical signal, it includes: The processing module fits a temperature change curve based on the current temperature value at different times.

9. A temperature sensing device, comprising: The acquisition circuit of the temperature sensor according to any one of claims 1-6.

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