Precise resistive sensor temperature measurement circuit and device

Abstract

The utility model provides a precise resistive sensor temperature measurement circuit and device, and relates to the technical field of temperature measurement circuits, through setting a proportional amplifier, ADC voltage at an output end of the proportional amplifier is only associated with a matching resistor (fixed resistance value) of a resistive temperature measurement sensor and a feedback resistor arranged in the proportional amplifier, so that the temperature measurement precision is improved. Therefore, the resistance value of the resistive temperature measurement sensor can be reversely calculated according to the collected ADC voltage, and the temperature of the current test point can be reflected according to the resistance value comparison table, which is irrelevant to the resistance value of the cable, so that the problem of inaccurate accuracy caused by long distance of the test temperature point is solved.

Description

Technical Field

[0001] The present application relates to the technical field of temperature measurement circuits, and in particular to a precision resistive sensor temperature measurement circuit and device. Background Art

[0002] Resistive temperature measurement circuits measure temperature by exploiting the temperature-dependent behavior of resistance. Common examples include platinum resistance and thermistor temperature measurement circuits. However, existing resistive temperature measurement circuits can exhibit significant errors, especially when the temperature measurement point is far away. The resistance of the transmission cable cannot be ignored, and accuracy decreases with increasing distance. Longer cables are also more susceptible to interference from other signals, leading to errors in the collected voltage. Utility Model Content

[0003] In order to overcome the deficiencies in the prior art, the present application provides a precision resistive sensor temperature measurement circuit and device, which can effectively solve the problem of decreased accuracy caused by the long distance between test temperature points.

[0004] The present application provides a precision resistive sensor temperature measurement circuit, comprising:

[0005] A resistive temperature sensor, wherein one end of the resistive temperature sensor is connected to a power supply via a fourteenth resistor R14, and the other end is connected to a first constant current source circuit via a fifteenth resistor R15 and a sixth resistor R6 in sequence; the other end of the resistive temperature sensor is connected to a second constant current source circuit via a sixteenth resistor R16; wherein the constant currents output by the first constant current source circuit and the second constant current source circuit are equal; the sixth resistor R6 is a matching resistor with a fixed resistance; the fourteenth resistor R14, the fifteenth resistor R15, and the sixteenth resistor R16 all represent resistances on a transmission cable, and the resistance values ​​of the fifteenth resistor R15 and the sixteenth resistor R16 are equal;

[0006] A two-stage proportional amplifier includes a first operational amplifier and a second operational amplifier, wherein the positive input terminal of the first operational amplifier is connected between the sixteenth resistor R16 and the second constant current source circuit via an eighth resistor R8, and one output terminal of the first operational amplifier is connected to the inverting input terminal of the second operational amplifier via an eleventh resistor R11, and the other output terminal is connected to ground via a ninth resistor R9 and a tenth resistor R10 in sequence, and the inverting input terminal of the second operational amplifier is connected between the ninth resistor R9 and the tenth resistor R10; the non-inverting input terminal of the second operational amplifier is connected between the sixth resistor R6 and the first constant current source circuit via a seventh resistor R7, and the output terminal of the second operational amplifier is connected to the inverting input terminal of the first constant current source circuit via a twelfth resistor R12; wherein the resistance values ​​of the ninth resistor R9 and the eleventh resistor R11 are equal, and the resistance values ​​of the tenth resistor R10 and the twelfth resistor R12 are equal.

[0007] In a possible implementation manner, the output voltage of the second operational amplifier is:

[0008] ADC=(U1-U2)*(R11+R12) / R11=I1*(R13-R6)*(R11+R12) / R11

[0009] Among them, U1 represents the voltage value of the non-inverting input terminal of the second operational amplifier, U2 represents the voltage value of the non-inverting input terminal of the first operational amplifier, I1 represents the constant current value output by the first constant current source circuit, and R13 represents the resistance value of the resistive temperature sensor; it is used to reversely calculate the resistance value of the resistive temperature sensor based on the collected output terminal voltage of the second operational amplifier, so as to reflect the current measured temperature according to the resistance value comparison table.

[0010] In one possible implementation, the first constant current source circuit includes a third operational amplifier and a first MOS transistor Q1. The gate of the first MOS transistor Q1 is connected to the output terminal of the third operational amplifier via a second resistor R2, the drain of the first MOS transistor Q1 is connected to the sixth resistor R6, and the source is grounded via a third resistor R3. The non-inverting input terminal of the third operational amplifier is connected to the output terminal of the voltage reference chip, and the inverting input terminal of the third operational amplifier is connected between the third resistor R3 and the source of the first MOS transistor Q1.

[0011] In one possible implementation, the reference terminal of the voltage reference chip is grounded, its output terminal and control terminal are connected to the non-inverting input terminal of the third operational amplifier on one path, and are connected to a DC5V power supply via a first resistor R1 on the other path, and a first capacitor C1 is further provided between the reference terminal and the output terminal of the voltage reference chip.

[0012] In one possible implementation, the second constant current source circuit includes a fourth operational amplifier and a second MOS transistor Q2. The gate of the second MOS transistor Q2 is connected to the output terminal of the fourth operational amplifier via a fifth resistor R5, the drain of the second MOS transistor Q2 is connected to the sixteenth resistor R16, and the source is grounded via a fourth resistor R4. The non-inverting input terminal of the fourth operational amplifier is connected to the output terminal of the voltage reference chip, and the inverting input terminal of the fourth operational amplifier is connected between the fourth resistor R4 and the source of the second MOS transistor Q2. The resistance values ​​of the third resistor R3 and the fourth resistor R4 are equal.

[0013] In one possible implementation, a third grounded capacitor C3 is further provided at the non-inverting input terminal of the first operational amplifier, a second grounded capacitor C2 is further provided at the non-inverting input terminal of the second operational amplifier, and a fourth capacitor C4 is further provided between the non-inverting input terminals of the first operational amplifier and the second operational amplifier, and the output terminal of the first operational amplifier is further connected between the ninth resistor R9 and the tenth resistor R10 via a fifth capacitor C5.

[0014] In a possible implementation manner, the voltage reference chip is a CJ431 chip, which provides a DC 2.5V voltage to the non-inverting input terminals of the third operational amplifier and the fourth operational amplifier.

[0015] In a possible implementation, the first operational amplifier, the second operational amplifier, the third operational amplifier, and the fourth operational amplifier are all GS8332.

[0016] The present application provides a precision resistive sensor temperature measurement device, which adopts any of the precision resistive sensor temperature measurement circuits described above.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] The precision resistive sensor temperature measurement circuit and device provided in this embodiment, by providing a proportional amplifier, causes the ADC voltage at its output end to be associated only with the matching resistor (fixed resistance) of the resistive temperature sensor and the feedback resistor provided in the proportional amplifier. This allows the resistance value of the resistive temperature sensor to be reversely calculated based on the collected ADC voltage, and then the temperature of the current test point to be reflected based on a resistance comparison table, regardless of the cable resistance. This solves the problem of inaccurate accuracy caused by the long distance between the test temperature points. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 A circuit diagram of a precision resistive sensor temperature measurement circuit according to an embodiment of the present application is shown;

[0021] Figure 2 A circuit diagram of a precision resistive sensor temperature measurement circuit according to another embodiment of the present application is shown. DETAILED DESCRIPTION

[0022] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application.

[0023] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0025] In this application, unless otherwise expressly specified or limited, terms such as "mounted," "connected," "connect," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components or interactions between two components. Those skilled in the art will understand the specific meanings of these terms in this application based on specific circumstances.

[0026] In this application, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0027] In view of the technical problems raised by the background technology, the present application provides a precision resistive sensor temperature measurement circuit and device, which can solve the problem of inaccurate accuracy caused by the long distance between the test temperature points.

[0028] See the instructions attached Figure 1 In one embodiment of the present application, a precision resistive sensor temperature measurement circuit is provided, comprising a resistive temperature sensor R13, a two-stage proportional amplifier, and a constant current source circuit. Specifically, the two-stage proportional amplifier comprises a first operational amplifier and a second operational amplifier, the constant current source circuit comprises a first constant current source circuit and a second constant current source circuit, the first constant current source circuit comprises a third operational amplifier and a first MOS tube Q1, the second constant current source circuit comprises a fourth operational amplifier and a second MOS tube Q2, wherein the first operational amplifier is represented by U5.2 in the figure, the second operational amplifier is represented by U5.1 in the figure, the third operational amplifier is represented by U4.1 in the figure, and the fourth operational amplifier is represented by U4.2 in the figure.

[0029] Specifically, one end of the resistive temperature sensor is connected to a power supply via a fourteenth resistor R14, and the other end is connected to a first constant current source circuit via a fifteenth resistor R15 and a sixth resistor R6 in sequence; the other end of the resistive temperature sensor is connected to a second constant current source circuit via a sixteenth resistor R16; wherein the constant currents output by the first constant current source circuit and the second constant current source circuit are equal;

[0030] The positive input terminal of the first operational amplifier is connected between the sixteenth resistor R16 and the second constant current source circuit via the eighth resistor R8, and one path of the output terminal of the first operational amplifier is connected to the inverting input terminal of the second operational amplifier via the eleventh resistor R11, and the other path is connected to ground via the ninth resistor R9 and the tenth resistor R10 in sequence, and the inverting input terminal of the first operational amplifier is connected between the ninth resistor R9 and the tenth resistor R10; the non-inverting input terminal of the second operational amplifier is connected between the sixth resistor R6 and the first constant current source circuit via the seventh resistor R7; and the non-inverting input terminal of the first operational amplifier is further provided with a grounded third capacitor C3, the non-inverting input terminal of the second operational amplifier is further provided with a grounded second capacitor C2, and a fourth capacitor C4 is further provided between the non-inverting input terminals of the first operational amplifier and the second operational amplifier, and the output terminal of the first operational amplifier is further connected between the ninth resistor R9 and the tenth resistor R10 via a fifth capacitor C5;

[0031] The gate of the first MOS transistor Q1 is connected to the output terminal of the third operational amplifier via the second resistor R2, the drain of the first MOS transistor Q1 is connected to the sixth resistor R6, and the source is grounded via the third resistor R3; the non-inverting input terminal of the third operational amplifier is connected to the output terminal of the voltage reference chip, and the inverting input terminal of the first MOS transistor Q1 is connected between the third resistor R3 and the source of the first MOS transistor Q1; the gate of the second MOS transistor Q2 is connected to the output terminal of the fourth operational amplifier via the fifth resistor R5, the drain of the first MOS transistor Q2 is connected to the sixteenth resistor R16, and the source is grounded via the fourth resistor R4; the fourth operational amplifier The non-inverting input terminal of the voltage reference chip U1 is connected to the output terminal of the voltage reference chip U1, the inverting input terminal of the voltage reference chip U1 is connected between the fourth resistor R4 and the source of the second MOS transistor Q2, and the output terminal of the voltage reference chip U1 is connected to the inverting input terminal of the voltage reference chip U1 through the twelfth resistor R12; wherein the resistance values ​​of the third resistor R3 and the fourth resistor R4 are equal; the reference terminal of the voltage reference chip U1 is grounded, the output terminal and the control terminal of the voltage reference chip U1 are connected to the non-inverting input terminal of the third operational amplifier on one path, and are connected to the DC5V power supply on the other path through the first resistor R1, and a first capacitor C1 is further provided between the reference terminal and the output terminal of the voltage reference chip U1.

[0032] Among them, the fourteenth resistor R14, the fifteenth resistor R15, and the sixteenth resistor R16 all represent resistors on the transmission cable; the ninth resistor R9, the tenth resistor R10, the eleventh resistor R11, and the twelfth resistor R12 are feedback resistors; the first resistor R1, the second resistor R2, the fifth resistor R5, the seventh resistor R7, and the eighth resistor R8 are current-limiting resistors; the first capacitor C1, the second capacitor C2, the third capacitor C3, the fourth capacitor C4, and the fifth capacitor C5 are filter capacitors. The voltage reference chip used is model CJ431, which provides a DC2.5V voltage to the non-inverting input terminal of the third operational amplifier and the fourth operational amplifier; the first operational amplifier, the second operational amplifier, the third operational amplifier, and the fourth operational amplifier are all model GS8332; the first MOS transistor Q1 and the second MOS transistor Q2 are both model 2N7002LT1G.

[0033] When calculating the ADC voltage at the output of the second operational amplifier:

[0034] I1=2.5 / R3,I2=2.5 / R4,wherein, I1 represents the constant current value output by the first constant current source circuit, I2 represents the constant current value output by the second constant current source circuit, the voltage U1 generated at the non-inverting input terminal (pin 3) of the second operational amplifier is U1=U1=5-(I1+I2)*R14-I1*R15-I1*R6, the voltage U2 generated at the non-inverting input terminal (pin 5) of the first operational amplifier is U2=5-(I1+I2)*R14-I2*R13-I2*R16, wherein, let the ninth resistor R 9 and the eleventh resistor R11 have the same resistance, then the output terminal ADC voltage is ADC = (U1-U2)*(R11+R12) / R11. Furthermore, assuming that the third resistor R3 and the fourth resistor R4 use the same resistance, then I1 = I2. The fifteenth resistor R15 and the sixteenth resistor R16 simulate the resistance of a transmission cable made of the same length and material. Therefore, the fifteenth resistor R15 and the sixteenth resistor R16 have the same resistance. Substituting U1 and U2 into the equation, the simplified equation is ADC = I1*(R13-R6)*(R11+R12) / R11.

[0035] Through the above formula, the resistance value of the resistive temperature sensor R13 can be reversely calculated based on the collected ADC voltage at the output end of the second operational amplifier, and then the current measured temperature can be reflected according to the resistance value comparison table of the resistive temperature sensor R13. This is independent of the cable resistance value. Therefore, no matter what the cable resistance value of the fourteenth resistor R14, the fifteenth resistor R15, and the sixteenth resistor R16 is, it will not affect the accuracy of the acquisition.

[0036] The precision resistive sensor temperature measurement circuit provided in the present application sets a proportional amplifier so that the ADC voltage at its output end is only associated with the matching resistor (fixed resistance) of the resistive temperature sensor and the feedback resistor set in the proportional amplifier. Therefore, the resistance value of the resistive temperature sensor can be reversely calculated based on the collected ADC voltage, and the temperature of the current test point can be reflected according to the resistance comparison table, regardless of the cable resistance, thereby solving the problem of inaccurate accuracy caused by the long distance between the test temperature points.

[0037] In another embodiment, the two-stage proportional amplifier can be replaced by a differential proportional amplifier, see the appendix of the specification. Figure 2 , provides a precision resistive sensor temperature measurement circuit, including a resistive temperature sensor R29, a third MOS tube Q3, a voltage reference chip U6, a fifth operational amplifier and a sixth operational amplifier consisting of a differential proportional amplifier, wherein the fifth operational amplifier is represented by U7.1 in the figure and the sixth operational amplifier is represented by U9.1 in the figure.

[0038] Specifically, one end of the resistive temperature sensor R29 is connected to the power supply via the 30th resistor R30, and the other end is connected to the non-inverting input terminal of the sixth operational amplifier via the 31st resistor R31 and the 34th resistor R34 in sequence. The other end of the resistive temperature sensor R29 is connected to the drain of the third MOS transistor Q3 via the 33rd resistor R33, and the other end is connected to the inverting input terminal of the sixth operational amplifier via the 32nd resistor R32 and the 35th resistor R35 in sequence. The non-inverting input terminal of the sixth operational amplifier is also connected via the 37th resistor R 37 is connected to a power supply, and its inverting input terminal is also connected to its output terminal via a thirty-sixth resistor; the reference terminal of the voltage reference chip U6 is grounded, and its output terminal and control terminal are connected to the non-inverting input terminal of the fifth operational amplifier in one path, and are connected to a DC5V power supply in the other path via a seventeenth resistor R17; the gate of the third MOS transistor Q3 is connected to the output terminal of the fifth operational amplifier via an eighteenth resistor R18, and its source is grounded via a nineteenth resistor R19. The inverting input terminal of the fifth operational amplifier is connected between the nineteenth resistor R19 and the source of the third MOS transistor Q3.

[0039] Among them, the fifth operational amplifier and the third MOS transistor Q3 form a constant current source circuit, the nineteenth resistor R19 is its adjustment resistor, the thirtieth resistor R30, the thirty-first resistor R31, the thirty-second resistor R32, and the thirty-third resistor R33 are resistors on the analog transmission cable, the thirty-fourth resistor R34, the thirty-fifth resistor R35, the thirty-sixth resistor R36, and the thirty-seventh resistor R37 are feedback resistors, and the seventeenth resistor R17 and the eighteenth resistor R18 are current limiting resistors.

[0040] When calculating the output terminal ADC voltage of the sixth operational amplifier:

[0041] The CJ431 voltage reference chip U6 is used to provide a 2.5V voltage to the non-inverting input terminal of the fifth operational amplifier. The constant current value I is output by the constant current source circuit formed by the fifth operational amplifier and the third MOS tube Q3. L =2.5 / R19, then the voltage U on the resistive temperature sensor R29 L =I L *R29, the voltage at the output terminal ADC of the sixth operational amplifier is ADC=U L *R36 / R35, based on the collected ADC value, reversely calculates the resistance value of the resistive temperature sensor R29, and then reflects the current measured temperature according to the resistance value comparison table of the resistive temperature sensor R29, regardless of the cable resistance. In this design, no matter what the cable resistance of the 30th resistor R30, the 31st resistor R31, the 32nd resistor R32, and the 33rd resistor R33 is, it will not affect the acquisition accuracy.

[0042] The present invention also provides a precision resistive sensor temperature measurement device that utilizes the aforementioned precision resistive sensor temperature measurement circuit to effectively address the issue of reduced accuracy caused by the distance between test temperature points. Because the principles underlying the temperature measurement device in the present embodiment are similar to those of the aforementioned temperature measurement circuit in the present embodiment, the implementation of the temperature measurement device can be referenced to the implementation of the temperature measurement circuit, and any repetitions will not be repeated.

[0043] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0044] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A precision resistive sensor temperature measurement circuit, characterized in that: include: A resistive temperature sensor, wherein one end of the resistive temperature sensor is connected to a power supply via a fourteenth resistor R14, and the other end is connected to a first constant current source circuit via a fifteenth resistor R15 and a sixth resistor R6 in sequence; the other end of the resistive temperature sensor is connected to a second constant current source circuit via a sixteenth resistor R16; wherein the constant currents output by the first constant current source circuit and the second constant current source circuit are equal; the sixth resistor R6 is a matching resistor with a fixed resistance; the fourteenth resistor R14, the fifteenth resistor R15, and the sixteenth resistor R16 all represent resistances on a transmission cable, and the resistance values ​​of the fifteenth resistor R15 and the sixteenth resistor R16 are equal; A two-stage proportional amplifier includes a first operational amplifier and a second operational amplifier, wherein the positive input terminal of the first operational amplifier is connected between the sixteenth resistor R16 and the second constant current source circuit via an eighth resistor R8, and one output terminal thereof is connected to the inverting input terminal of the second operational amplifier via an eleventh resistor R11, and the other output terminal is connected to ground via a ninth resistor R9 and a tenth resistor R10 in sequence, and the inverting input terminal thereof is connected between the ninth resistor R9 and the tenth resistor R10; the positive input terminal of the second operational amplifier is connected between the sixth resistor R6 and the first constant current source circuit via a seventh resistor R7, and the output terminal thereof is connected to the inverting input terminal thereof via a twelfth resistor R12; wherein the resistance values ​​of the ninth resistor R9 and the eleventh resistor R11 are equal, and the resistance values ​​of the tenth resistor R10 and the twelfth resistor R12 are equal; and the output terminal voltage of the second operational amplifier is: ADC=(U1-U2)*(R11+R12) / R11=I1*(R13-R6)*(R11+R12) / R11 Among them, U1 represents the voltage value of the non-inverting input terminal of the second operational amplifier, U2 represents the voltage value of the non-inverting input terminal of the first operational amplifier, I1 represents the constant current value output by the first constant current source circuit, and R13 represents the resistance value of the resistive temperature sensor; it is used to reversely calculate the resistance value of the resistive temperature sensor based on the collected output terminal voltage of the second operational amplifier, so as to reflect the current measured temperature according to the resistance value comparison table.

2. The precision resistive sensor temperature measurement circuit according to claim 1, characterized in that: The first constant current source circuit includes a third operational amplifier and a first MOS transistor Q1. The gate of the first MOS transistor Q1 is connected to the output end of the third operational amplifier via a second resistor R2, the drain of the first MOS transistor Q1 is connected to the sixth resistor R6, and the source is grounded via a third resistor R3. The non-inverting input end of the third operational amplifier is connected to the output end of the voltage reference chip, and the inverting input end is connected between the third resistor R3 and the source of the first MOS transistor Q1.

3. The precision resistive sensor temperature measurement circuit according to claim 2, characterized in that: The reference end of the voltage reference chip is grounded, and its output end and control end are connected to the non-inverting input end of the third operational amplifier on one path, and connected to a DC5V power supply via a first resistor R1 on the other path. A first capacitor C1 is also provided between the reference end and the output end of the voltage reference chip.

4. The precision resistive sensor temperature measurement circuit according to claim 3, characterized in that: The second constant current source circuit includes a fourth operational amplifier and a second MOS transistor Q2. The gate of the second MOS transistor Q2 is connected to the output terminal of the fourth operational amplifier via a fifth resistor R5, the drain of the second MOS transistor Q2 is connected to the sixteenth resistor R16, and the source is grounded via a fourth resistor R4. The non-inverting input terminal of the fourth operational amplifier is connected to the output terminal of the voltage reference chip, and the inverting input terminal is connected between the fourth resistor R4 and the source of the second MOS transistor Q2. The resistance values ​​of the third resistor R3 and the fourth resistor R4 are equal.

5. The precision resistive sensor temperature measurement circuit according to claim 4, characterized in that: A third grounded capacitor C3 is further provided at the non-inverting input terminal of the first operational amplifier, a second grounded capacitor C2 is further provided at the non-inverting input terminal of the second operational amplifier, and a fourth capacitor C4 is further provided between the non-inverting input terminals of the first operational amplifier and the second operational amplifier. In addition, the output terminal of the first operational amplifier is further connected between the ninth resistor R9 and the tenth resistor R10 via a fifth capacitor C5.

6. The precision resistive sensor temperature measurement circuit according to claim 5, characterized in that: The voltage reference chip is of model CJ431, which provides a DC2.5V voltage to the non-inverting input terminals of the third operational amplifier and the fourth operational amplifier.

7. The precision resistive sensor temperature measurement circuit according to claim 6, characterized in that: The first operational amplifier, the second operational amplifier, the third operational amplifier and the fourth operational amplifier are all GS8332.

8. A precision resistive sensor temperature measuring device, characterized in that: The invention comprises the precision resistive sensor temperature measurement circuit described in any one of claims 1 to 7.

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