Temperature detection circuit and temperature compensation system

Abstract

The invention belongs to the technical field of electronic circuits, and provides a temperature detection circuit and a temperature compensation system. The temperature detection circuit comprises a voltage generation module, a temperature acquisition module, a selection module, a conversion module and a control module, the selection module is respectively connected with the voltage generation module, the temperature acquisition module, the conversion module and the control module, the control module is connected with the conversion module, and the control module and the conversion module are both connected with the power supply module. The voltage generation module generates a reference voltage; the temperature acquisition module acquires environment temperature; the control module outputs a first control signal to the selection module and outputs a first trigger signal to the conversion module; the selection module transmits the reference voltage to the conversion module according to the first control signal; the conversion module starts to work according to the first trigger signal and converts the reference voltage to obtain a first signal; the control module also determines a target error according to the first signal, and determines whether to control the selection module to transmit the environment temperature to the conversion module according to the target error.

Description

Technical Field

[0001] The present application belongs to the technical field of electronic circuits, and in particular, relates to a temperature detection circuit and a temperature compensation system. Background Art

[0002] In the current temperature compensation method, a lookup table or function generator of crystal frequency and temperature is usually built in. Among them, the parameters of the lookup table or function generator are obtained by testing by the chip manufacturer. During the test, a constant voltage source is used to power the crystal oscillator circuit, and the temperature value is detected by a temperature detection circuit composed of a temperature sensor and an analog-to-digital converter, and the relevant parameters of the lookup table or function generator are calculated according to the temperature value.

[0003] However, the crystal oscillator circuit is actually powered by a battery. During operation, the battery supply voltage will fluctuate or even drop. If the analog-to-digital converter in the temperature detection circuit has poor resistance to power supply fluctuations, or the battery supply voltage is lower than the working threshold voltage of the analog-to-digital converter, the temperature value output by the analog-to-digital converter will have errors or even abnormalities, affecting the temperature compensation of the crystal oscillator. Therefore, the current temperature detection circuit is affected by the power supply voltage and has the problem of low temperature detection accuracy. Summary of the invention

[0004] The embodiments of the present application provide a temperature detection circuit and a temperature compensation system, which can solve the problem that the current temperature detection circuit is affected by the power supply voltage and has low temperature detection accuracy.

[0005] In a first aspect, an embodiment of the present application provides a temperature detection circuit, including a voltage generating module, a temperature acquisition module, a selection module, a conversion module and a control module, wherein the selection module is respectively connected to the voltage generating module, the temperature acquisition module, the conversion module and the control module, the control module is connected to the conversion module, and the control module and the conversion module are both used to be connected to a power supply module;

[0006] The voltage generating module is used to generate a reference voltage; the temperature acquisition module is used to acquire the ambient temperature; the control module is used to output a first control signal to the selection module and a first trigger signal to the conversion module; the selection module is used to transmit the reference voltage to the conversion module according to the first control signal; the conversion module is used to start working according to the first trigger signal and convert the reference voltage to obtain a first signal; the control module is also used to determine a target error according to the first signal, and determine whether to control the selection module to transmit the ambient temperature to the conversion module according to the target error.

[0007] In a possible implementation manner of the first aspect, the control module includes a control unit and a correction unit, the control unit is respectively connected to the selection module, the conversion module, the correction unit and the power module, and the correction unit is connected to the conversion module;

[0008] The control unit is used to output the first control signal to the selection module, output the first trigger signal to the conversion module, and output the second trigger signal to the correction unit; the correction unit is used to start working according to the second trigger signal and determine the target error according to the received first signal; the control unit is used to determine whether to control the selection module to transmit the ambient temperature to the conversion module according to the target error.

[0009] In a possible implementation of the first aspect, the control unit is also used to compare the target error with a preset threshold value, and when the target error is less than the preset threshold value, output a first instruction to the correction unit so that the correction unit saves the target error according to the first instruction, and output a second control signal to the selection module so that the selection module transmits the ambient temperature to the conversion module according to the second control signal; the conversion module is also used to convert the ambient temperature and output a second signal to the correction unit; the correction unit is also used to obtain the compensated ambient temperature according to the second signal and the target error, and save the compensated ambient temperature.

[0010] In a possible implementation of the first aspect, the control unit is also used to control the correction unit to discard the target error when the target error is greater than or equal to a preset threshold; control the selection module to transmit the reference voltage to the conversion module; control the conversion module to enter a sleep state; control the correction unit to enter a standby state, and enable the correction unit to output the compensated ambient temperature it saves.

[0011] In a possible implementation manner of the first aspect, the control unit includes a controller, and the controller is respectively connected to the selection module, the conversion module, the correction unit, and the power supply module.

[0012] In a possible implementation manner of the first aspect, the conversion module includes an analog-to-digital converter, and the analog-to-digital converter is respectively connected to the selection module, the control module, and the power supply module.

[0013] In a possible implementation manner of the first aspect, the temperature acquisition module includes a temperature sensor, and the temperature sensor is connected to the selection module.

[0014] In a possible implementation of the first aspect, the selection module includes a two-to-one selector, a first end of the two-to-one selector is connected to the voltage generation module, a second end of the two-to-one selector is connected to the temperature acquisition module, a third end of the two-to-one selector is connected to the conversion module, and a control end of the two-to-one selector is connected to the control module.

[0015] In a possible implementation of the first aspect, the voltage generating module includes an operational amplifier, a first resistor, a second resistor, a third resistor, a first capacitor and a first field effect transistor, the first input terminal of the operational amplifier is used to receive a first voltage, the second input terminal of the operational amplifier is respectively connected to the second end of the second resistor and the first end of the third resistor, the output terminal of the operational amplifier is respectively connected to the first end of the first resistor and the gate of the first field effect transistor, the second end of the first resistor is connected to the first end of the first capacitor, the second end of the first capacitor is respectively connected to the first end of the second resistor, the drain of the first field effect transistor and the selection module, the source of the first field effect transistor receives a power supply voltage, and the second end of the third resistor is grounded.

[0016] In a second aspect, an embodiment of the present application provides a temperature compensation system, comprising the temperature detection circuit described in any one of the first aspects.

[0017] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0018] An embodiment of the present application provides a temperature detection circuit, including a voltage generating module, a temperature acquisition module, a selection module, a conversion module and a control module, wherein the selection module is respectively connected to the voltage generating module, the temperature acquisition module, the conversion module and the control module, the control module is connected to the conversion module, and both the control module and the conversion module are used to be connected to a power supply module.

[0019] The voltage generation module is used to generate a reference voltage. The temperature acquisition module is used to acquire the ambient temperature. The control module is used to output a first control signal to the selection module and a first trigger signal to the conversion module. The selection module is used to transmit the reference voltage to the conversion module according to the first control signal. The conversion module is used to start working according to the first trigger signal and convert the reference voltage to obtain a first signal. The control module is also used to determine a target error according to the first signal, and determine whether to control the selection module to transmit the ambient temperature to the conversion module according to the target error.

[0020] The temperature detection circuit provided in the present application converts the reference voltage before the conversion module converts the ambient temperature, and transmits the first signal obtained after the conversion to the control module. The control module determines the target error based on the first signal, and the target error reflects the accuracy and stability of the conversion module when processing the reference voltage, and also indirectly reflects the stability of the output voltage of the power module. The control module can evaluate the stability of the output voltage of the power module based on the target error, and then determine whether to transmit the ambient temperature to the conversion module for conversion, so as to avoid the conversion error caused by the voltage fluctuation output by the power module, and finally realize the accurate detection of the ambient temperature.

[0021] In summary, the temperature detection circuit provided in the embodiments of the present application solves the problem that the current temperature detection circuit is affected by the power supply voltage and has low temperature detection accuracy.

[0022] It can be understood that the beneficial effects of the second aspect mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0024] Figure 1 is a principle block diagram of a temperature detection circuit provided in an embodiment of the present application;

[0025] Figure 2 is a principle block diagram of a temperature detection circuit provided in another embodiment of the present application;

[0026] Figure 3 is an application schematic diagram of a temperature detection circuit provided by an embodiment of the present application;

[0027] Figure 4 is a temperature detection flow chart of a temperature detection circuit provided by an embodiment of the present application;

[0028] Figure 5 It is a schematic diagram of changes in power supply voltage and output temperature of a temperature detection circuit provided in an embodiment of the present application;

[0029] Figure 6 Schematic diagram of the circuit structure of a temperature detection circuit provided in one embodiment of the present application.

[0030] In the figure: 11, voltage generating module; 12, temperature collecting module; 13, selecting module; 14, converting module; 15, controlling module; 151, controlling unit; 152, correcting unit; 16, power supply module; 21, crystal oscillator; 22, clock generating circuit; 23, temperature compensation circuit. DETAILED DESCRIPTION

[0031] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0032] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof.

[0033] It should also be understood that the term “and / or” used in the specification and appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0034] As used in the specification and appended claims of this application, the term "if" can be interpreted as "when" or "uponce" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" can be interpreted as meaning "uponce it is determined" or "in response to determining" or "uponce [described condition or event] is detected" or "in response to detecting [described condition or event]", depending on the context.

[0035] In addition, in the description of the present application specification and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.

[0036] References to "one embodiment" or "some embodiments" etc. described in the specification of this application mean that one or more embodiments of the present application include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the statements "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0037] In the field of electric energy meters, a low-speed crystal oscillator circuit of 32768Hz is usually used to generate a real-time clock. Since the crystal oscillator is easily affected by the ambient temperature, the generated real-time clock cannot meet the high-precision requirements of the electric energy meter field. Therefore, it is necessary to set a temperature detection circuit and a temperature compensation circuit in the crystal oscillator circuit. The temperature detection circuit detects the ambient temperature, and the temperature compensation circuit compensates the crystal oscillator according to the detected ambient temperature.

[0038] In the current temperature compensation method, a lookup table or function generator of crystal frequency and temperature is usually built in. Among them, the parameters of the lookup table or function generator are obtained by testing by the chip manufacturer. During the test, a constant voltage source is used to power the crystal oscillator circuit, and the temperature value is detected by a temperature detection circuit composed of a temperature sensor and an analog-to-digital converter, and the relevant parameters of the lookup table or function generator are calculated according to the temperature value.

[0039] However, the crystal oscillator circuit is actually powered by a battery. During operation, the battery supply voltage will fluctuate or even drop. If the analog-to-digital converter in the temperature detection circuit has poor resistance to power supply fluctuations, or the battery supply voltage is lower than the working threshold voltage of the analog-to-digital converter, the temperature value output by the analog-to-digital converter will have errors or even abnormalities, affecting the temperature compensation of the crystal oscillator. Therefore, the current temperature detection circuit is affected by the power supply voltage and has the problem of low temperature detection accuracy.

[0040] In view of the above problems, the present application provides a temperature detection circuit. Figure 1As shown, the temperature detection circuit includes a voltage generating module 11, a temperature acquisition module 12, a selection module 13, a conversion module 14 and a control module 15, the selection module 13 is respectively connected to the voltage generating module 11, the temperature acquisition module 12, the conversion module 14 and the control module 15, the control module 15 is connected to the conversion module 14, and the control module 15 and the conversion module 14 are both used to connect to the power module 16. In the embodiment of the present application, the power module 16 is a battery, which is used to power the conversion module 14 and the control module 15. The power module 16 can also be used as a power supply for the voltage generating module 11, the temperature acquisition module 12 and the selection module 13, and power the voltage generating module 11, the temperature acquisition module 12 and the selection module 13.

[0041] Specifically, the voltage generating module 11 is used to generate a reference voltage, and the reference voltage is not affected by the ambient temperature and the power supply voltage. It should be noted that the reference voltage is greater than the voltage threshold for the normal operation of the temperature detection circuit and is less than the reference voltage of the conversion module 14. The temperature acquisition module 12 is used to collect the ambient temperature. The control module 15 is used to output a first control signal to the selection module 13 and a first trigger signal to the conversion module 14. It should be noted that the control module 15 is used to output a first control signal to the selection module 13 and a first trigger signal to the conversion module 14 within a fixed time period. Since the ambient temperature will not change suddenly, the time period can be selected as a second or ten seconds. The selection module 13 is used to transmit the reference voltage to the conversion module 14 according to the first control signal. The conversion module 14 is used to start working according to the first trigger signal and convert the reference voltage to obtain a first signal, which is a digital code value signal corresponding to the reference voltage. The control module 15 is also used to determine the target error according to the first signal, and determine whether to control the selection module 13 to transmit the ambient temperature to the conversion module 14 according to the target error. Among them, the target error is the error generated by the temperature detection circuit.

[0042] The temperature detection circuit provided in the present application converts the reference voltage before the conversion module 14 converts the ambient temperature, and transmits the first signal obtained after the conversion to the control module 15. The control module 15 determines the target error based on the first signal, and the target error reflects the accuracy and stability of the conversion module 14 when processing the reference voltage, and also indirectly reflects the stability of the output voltage of the power module 16. The control module 15 can evaluate the stability of the output voltage of the power module 16 based on the target error, and then determine whether to transmit the ambient temperature to the conversion module 14 for conversion, so as to avoid the conversion error caused by the voltage fluctuation output by the power module 16, and finally realize the accurate detection of the ambient temperature.

[0043] In summary, the temperature detection circuit provided in the embodiments of the present application solves the problem that the current temperature detection circuit is affected by the power supply voltage and has low temperature detection accuracy.

[0044] In some embodiments, Figure 2 As shown, the control module 15 includes a control unit 151 and a correction unit 152 . The control unit 151 is respectively connected to the selection module 13 , the conversion module 14 , the correction unit 152 and the power module 16 , and the correction unit 152 is connected to the conversion module 14 .

[0045] Specifically, the control unit 151 is used to output a first control signal to the selection module 13, so that the selection module 13 transmits the reference voltage to the conversion module 14 according to the first control signal, output a first trigger signal to the conversion module 14, so that the conversion module 14 starts working according to the first trigger signal, and output a second trigger signal to the correction unit 152, so that the correction unit 152 starts working according to the second trigger signal. It should be noted that the control unit 151 is used to output the first control signal to the selection module 13 within a fixed time period, output the first trigger signal to the conversion module 14, and output the second trigger signal to the correction unit 152. Among them, the first control signal, the first trigger signal, and the second trigger signal can be level signals. The correction unit 152 is used to start working according to the second trigger signal and determine the target error according to the received first signal. The control unit 151 is used to determine whether to control the selection module 13 to transmit the ambient temperature to the conversion module 14 according to the target error.

[0046] The temperature detection circuit provided in the present application first converts the reference voltage before the conversion module 14 converts the ambient temperature, and transmits the first signal obtained after the conversion to the correction unit 152. The correction unit 152 determines the target error based on the first signal. The target error reflects the accuracy and stability of the conversion module 14 when processing the reference voltage, and also indirectly reflects the stability of the output voltage of the power module 16. The control unit 151 can evaluate the stability of the output voltage of the power module 16 based on the target error, and then determine whether to transmit the ambient temperature to the conversion module 14 for conversion, so as to avoid the conversion error caused by the voltage fluctuation output by the power module 16, and finally achieve accurate detection of the ambient temperature.

[0047] More specifically, after receiving the first signal, the correction unit 152 calculates the deviation between the first signal and a preset signal, and the deviation is the target error; wherein the preset signal is an ideal code value signal corresponding to the reference voltage.

[0048] In some embodiments, the control unit 151 is also used to compare the target error with a preset threshold value. When the target error is less than the preset threshold value, the control unit 151 outputs a first instruction to the correction unit 152, so that the correction unit 152 saves the target error according to the first instruction, and outputs a second control signal to the selection module 13, so that the selection module 13 transmits the ambient temperature to the conversion module 14 according to the second control signal. The conversion module 14 is also used to convert the ambient temperature and output a second signal to the correction unit 152. The correction unit 152 is also used to obtain the compensated ambient temperature according to the second signal and the target error, and save the compensated ambient temperature. Among them, the second control signal can be a level signal, the second signal is a digital code value signal corresponding to the ambient temperature, and the preset threshold can be set according to the actual situation, and this application does not limit this.

[0049] It can be seen from the above that when the target error is less than the preset threshold, it means that the target error is within an acceptable range, which also indirectly reflects that the voltage output by the power module 16 is relatively stable. Therefore, the ambient temperature can be converted. In order to improve the accuracy of temperature detection, after the ambient temperature is converted, the correction unit 152 will compensate for the ambient temperature according to the target error. In this way, the error caused by the output voltage fluctuation of the power module 16 or the insufficient accuracy of the conversion module 14 can be further reduced.

[0050] In some embodiments, the control unit 151 is also used to control the correction unit 152 to discard the target error when the target error is greater than or equal to a preset threshold; control the selection module 13 to transmit the reference voltage to the conversion module 14; control the conversion module 14 to enter a sleep state; control the correction unit 152 to enter a standby state, and enable the correction unit 152 to output the compensated ambient temperature it saves.

[0051] As can be seen from the above, when the target error is greater than or equal to the preset threshold, it means that the target error is not within the acceptable range, which also indirectly reflects that the voltage output by the power module 16 varies greatly and cannot meet the voltage required for normal operation of the circuit. In this case, the ambient temperature is not converted. Since the ambient temperature will not change suddenly, the compensated ambient temperature previously saved by the correction unit 152 can be output at this time to ensure the continuity of the temperature detection data.

[0052] The temperature detection circuit provided in the embodiment of the present application is applied to a crystal oscillator circuit, and the temperature detection process of the present application is further described in detail.

[0053] like Figure 3As shown, the crystal oscillator circuit includes a crystal oscillator 21, a clock generating circuit 22 and a temperature compensation circuit 23, and the clock generating circuit 22 is respectively connected to the crystal oscillator 21 and the temperature compensation circuit 23. The control unit 151 in the present application is connected to the clock generating circuit 22, and the correction unit 152 in the present application is connected to the temperature compensation circuit 23.

[0054] Specifically, the correction unit 152 is used to output the compensated ambient temperature to the temperature compensation circuit 23. The crystal oscillator 21 is used to output a low-speed clock of 32768 Hz. The temperature compensation circuit 23 is used to determine the compensation amount of the crystal oscillator clock according to the compensated ambient temperature and transmit it to the clock generation circuit. The clock generation circuit 22 is used to generate a stable real-time clock according to the low-speed clock of 32768 Hz and the compensation amount of the crystal oscillator 21 clock, providing an optional timing service for this application.

[0055] The temperature detection process of the temperature detection circuit provided in the embodiment of the present application is as follows: Figure 4 As shown, in the entire detection process, the voltage generating module 11 and the temperature collecting module 12 are always in working state, the voltage generating module 11 is used to generate a reference voltage, and the temperature collecting module 12 is used to collect the ambient temperature.

[0056] 1) The control unit 151 waits for the cycle start signal of the real-time clock and starts the real-time detection process;

[0057] 2) The control unit 151 controls the selection module 13 to transmit the reference voltage to the conversion module 14;

[0058] 3) The conversion module 14 is triggered and converts the reference voltage to obtain a first signal;

[0059] 4) The correction unit 152 is triggered and determines the target error according to the first signal;

[0060] 5) The control unit 151 compares the target error with a preset threshold value, and if the target error is less than the preset threshold value, executes 6); if the target error is greater than or equal to the preset threshold value, executes 11);

[0061] 6) the correction unit 152 saves the target error according to the first instruction issued by the control unit 151;

[0062] 7) The control unit 151 controls the selection module 13 to transmit the ambient temperature to the conversion module 14;

[0063] 8) The conversion module 14 converts the ambient temperature to obtain a second signal;

[0064] 9) The correction unit 152 obtains the compensated ambient temperature according to the second signal and the target error;

[0065] 10) The correction unit 152 saves the compensated ambient temperature and outputs it to the temperature compensation circuit. The temperature detection process ends and returns to 1);

[0066] 11) The control unit 151 controls the correction unit 152 to discard the target error;

[0067] 12) The control unit 151 controls the selection module 13 to transmit the reference voltage to the conversion module 14;

[0068] 13) The control unit 151 controls the conversion module 14 to enter a dormant state and controls the correction unit 152 to enter a standby state;

[0069] 14) The correction unit 152 outputs the compensated ambient temperature saved in the previous cycle and proceeds to 10).

[0070] Figure 5 A schematic diagram of the change of the power supply voltage and output temperature of the temperature detection circuit is given, as shown in Figure 5 As shown in the figure, the power supply voltage changes at point M1, but the fluctuation is within an acceptable range, that is, the target error is less than the preset threshold. It is only necessary to compensate the target error to the measured ambient temperature to achieve accurate detection of the ambient temperature. When the power supply voltage is at points M2 and M3, the power supply voltage drops to a voltage threshold that exceeds the normal operation of the circuit. At this time, the measured target error is greater than the preset threshold, so the temperature measurement channel will be closed and the compensated ambient temperature saved before will be output. At point M4, the power supply voltage has returned to the normal voltage fluctuation range, so the measured target error is less than the preset threshold, then the temperature measurement channel will be reopened, and the compensated ambient temperature will be output eventually.

[0071] For example, Figure 6 As shown, the control unit 151 includes a controller, which is respectively connected to the selection module 13, the conversion module 14, the correction unit 152 and the power module 16. The present application does not limit the specific type of the controller.

[0072] For example, Figure 6 As shown, the conversion module 14 includes an analog-to-digital converter, which is connected to the selection module 13, the control module 15 and the power supply module 16 respectively.

[0073] For example, Figure 6 As shown, the temperature acquisition module 12 includes a temperature sensor, and the temperature sensor is connected to the selection module 13 .

[0074] For example, Figure 6As shown, the selection module 13 includes a two-to-one selector, a first end B0 of the two-to-one selector is connected to the voltage generating module 11, a second end B1 of the two-to-one selector is connected to the temperature acquisition module 12, a third end A of the two-to-one selector is connected to the conversion module 14, and a control end SEL of the two-to-one selector is connected to the control module 15.

[0075] For example, Figure 6 As shown, the voltage generating module 11 includes an operational amplifier, a first resistor R1, a second resistor R2, a third resistor R3, a first capacitor C1 and a first field effect transistor M1, the first input terminal in of the operational amplifier is used to receive the first voltage V1, the second input terminal ip of the operational amplifier is respectively connected to the second end of the second resistor R2 and the first end of the third resistor R3, the output terminal of the operational amplifier is respectively connected to the first end of the first resistor R1 and the gate of the first field effect transistor M1, the second end of the first resistor R1 is connected to the first end of the first capacitor C1, the second end of the first capacitor C1 is respectively connected to the first end of the second resistor R2, the drain of the first field effect transistor M1 and the selection module 13, the source of the first field effect transistor M1 receives the power supply voltage VCC, the power supply voltage VCC can be provided by the power supply module 16, and the second end of the third resistor R3 is grounded. Among them, the first resistor R1 and the first capacitor C1 play a filtering role.

[0076] Specifically, by using the virtual short characteristic of the operational amplifier, the voltage on the third resistor R3 can be obtained as the first voltage V1, and then the current flowing through the branch where the third resistor R3 is located can be obtained, thereby determining the reference voltage.

[0077] In summary, the temperature detection circuit provided in the embodiment of the present application converts the reference voltage before the conversion module 14 converts the ambient temperature, and transmits the first signal obtained after the conversion to the control module 15. The control module 15 determines the target error according to the first signal, and the target error reflects the accuracy and stability of the conversion module 14 when processing the reference voltage, and also indirectly reflects the stability of the output voltage of the power module 16. The control module 15 can evaluate the stability of the output voltage of the power module 16 according to the target error. When the target error is less than the preset threshold, it means that the voltage output by the power module 16 is relatively stable. Therefore, the selection module 13 can be controlled to transmit the ambient temperature to the conversion module 14, so that the conversion module 14 converts the ambient temperature, and performs error compensation on the converted ambient temperature, which can further reduce the error caused by the output voltage fluctuation of the power module 16 or the insufficient accuracy of the conversion module 14. When the target error is greater than or equal to the preset error, it means that the voltage output by the power module 16 changes greatly and cannot meet the voltage for normal operation of the circuit. In this case, the ambient temperature is not converted. Since the ambient temperature will not change suddenly, the compensated ambient temperature saved previously can be output to ensure the continuity of the temperature detection data.

[0078] The embodiment of the present application also provides a temperature compensation system, including the temperature detection circuit described above. Since the temperature compensation system provided in the embodiment of the present application adopts all the technical solutions of all the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0079] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0080] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A temperature detection circuit, characterized in that: It includes a voltage generating module, a temperature collecting module, a selecting module, a converting module and a controlling module, wherein the selecting module is respectively connected to the voltage generating module, the temperature collecting module, the converting module and the controlling module, the controlling module is connected to the converting module, and the controlling module and the converting module are both used to be connected to a power supply module; The voltage generating module is used to generate a reference voltage; the temperature acquisition module is used to acquire the ambient temperature; the control module is used to output a first control signal to the selection module and a first trigger signal to the conversion module; the selection module is used to transmit the reference voltage to the conversion module according to the first control signal; the conversion module is used to start working according to the first trigger signal and convert the reference voltage to obtain a first signal; the control module is also used to determine a target error according to the first signal, and determine whether to control the selection module to transmit the ambient temperature to the conversion module according to the target error.

2. The temperature detection circuit according to claim 1, characterized in that: The control module includes a control unit and a correction unit, the control unit is respectively connected to the selection module, the conversion module, the correction unit and the power module, and the correction unit is connected to the conversion module; The control unit is used to output the first control signal to the selection module, output the first trigger signal to the conversion module, and output the second trigger signal to the correction unit; the correction unit is used to start working according to the second trigger signal and determine the target error according to the received first signal; the control unit is used to determine whether to control the selection module to transmit the ambient temperature to the conversion module according to the target error.

3. The temperature detection circuit according to claim 2, characterized in that: The control unit is also used to compare the target error with a preset threshold value, and when the target error is less than the preset threshold value, output a first instruction to the correction unit so that the correction unit saves the target error according to the first instruction, and output a second control signal to the selection module so that the selection module transmits the ambient temperature to the conversion module according to the second control signal; the conversion module is also used to convert the ambient temperature and output a second signal to the correction unit; the correction unit is also used to obtain the compensated ambient temperature according to the second signal and the target error, and save the compensated ambient temperature.

4. The temperature detection circuit according to claim 2, characterized in that: The control unit is also used to control the correction unit to discard the target error when the target error is greater than or equal to a preset threshold; control the selection module to transmit the reference voltage to the conversion module; control the conversion module to enter a sleep state; control the correction unit to enter a standby state, and enable the correction unit to output the compensated ambient temperature it saves.

5. The temperature detection circuit according to any one of claims 2 to 4, characterized in that: The control unit includes a controller, and the controller is respectively connected to the selection module, the conversion module, the correction unit and the power supply module.

6. The temperature detection circuit according to any one of claims 2 to 4, characterized in that: The conversion module includes an analog-to-digital converter, and the analog-to-digital converter is respectively connected to the selection module, the control module and the power supply module.

7. The temperature detection circuit according to any one of claims 2 to 4, characterized in that: The temperature acquisition module includes a temperature sensor, and the temperature sensor is connected to the selection module.

8. The temperature detection circuit according to any one of claims 2 to 4, characterized in that: The selection module includes a two-choice selector, a first end of the two-choice selector is connected to the voltage generation module, a second end of the two-choice selector is connected to the temperature acquisition module, a third end of the two-choice selector is connected to the conversion module, and a control end of the two-choice selector is connected to the control module.

9. The temperature detection circuit according to any one of claims 2 to 4, characterized in that: The voltage generating module includes an operational amplifier, a first resistor, a second resistor, a third resistor, a first capacitor and a first field effect transistor. The first input end of the operational amplifier is used to receive a first voltage. The second input end of the operational amplifier is respectively connected to the second end of the second resistor and the first end of the third resistor. The output end of the operational amplifier is respectively connected to the first end of the first resistor and the gate of the first field effect transistor. The second end of the first resistor is connected to the first end of the first capacitor. The second end of the first capacitor is respectively connected to the first end of the second resistor, the drain of the first field effect transistor and the selection module. The source of the first field effect transistor receives the power supply voltage. The second end of the third resistor is grounded.

10. A temperature compensation system, characterized in that: The temperature detection circuit comprises the temperature detection circuit according to any one of claims 1 to 9.

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