CN110440945B - High-precision low-temperature drift discrete type double-matching constant current source temperature measuring circuit - Google Patents
High-precision low-temperature drift discrete type double-matching constant current source temperature measuring circuit Download PDFInfo
- Publication number
- CN110440945B CN110440945B CN201910793766.2A CN201910793766A CN110440945B CN 110440945 B CN110440945 B CN 110440945B CN 201910793766 A CN201910793766 A CN 201910793766A CN 110440945 B CN110440945 B CN 110440945B
- Authority
- CN
- China
- Prior art keywords
- resistor
- double
- operational amplifier
- analog
- constant current
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims abstract description 34
- 229910052697 platinum Inorganic materials 0.000 claims abstract description 17
- 230000000087 stabilizing effect Effects 0.000 claims abstract description 14
- 239000003990 capacitor Substances 0.000 claims abstract description 10
- 238000009529 body temperature measurement Methods 0.000 claims abstract description 4
- 238000005259 measurement Methods 0.000 abstract description 6
- 238000006243 chemical reaction Methods 0.000 abstract description 5
- 238000005070 sampling Methods 0.000 abstract description 2
- 238000000034 method Methods 0.000 description 4
- 230000001419 dependent effect Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000009795 derivation Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K7/00—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements
- G01K7/16—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements
- G01K7/18—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements the element being a linear resistance, e.g. platinum resistance thermometer
- G01K7/20—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements the element being a linear resistance, e.g. platinum resistance thermometer in a specially-adapted circuit, e.g. bridge circuit
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05F—SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES
- G05F1/00—Automatic systems in which deviations of an electric quantity from one or more predetermined values are detected at the output of the system and fed back to a device within the system to restore the detected quantity to its predetermined value or values, i.e. retroactive systems
- G05F1/10—Regulating voltage or current
- G05F1/46—Regulating voltage or current wherein the variable actually regulated by the final control device is dc
- G05F1/56—Regulating voltage or current wherein the variable actually regulated by the final control device is dc using semiconductor devices in series with the load as final control devices
- G05F1/561—Voltage to current converters
Abstract
The invention relates to a high-precision low-temperature drift discrete double-matching constant current source temperature measuring circuit, and belongs to the technical field of temperature measurement. The invention aims to solve the technical problems of high dependence on an analog-to-digital converter and low signal measurement expansibility of the existing double-matching constant current source. The technical scheme adopted by the invention is as follows: a high-precision low-temperature drift discrete double-matching constant current source temperature measuring circuit consists of a platinum resistor Rt, a voltage stabilizing chip U1, three double operational amplifiers U2, U3 and U4, an analog-to-digital converter U5, a symmetrical transistor U6, 16 resistors R1-R16 and a capacitor C1. The invention adopts a split double-matching constant current source circuit to provide two paths of matched constant current sources for the temperature measuring circuit, and can lead the signal sampling part, the signal amplifying part and the analog-to-digital conversion part to be independent. The invention has the advantages of discrete functional parts, convenience for multipath PT100 expansion or measurement of other analog quantities, reduced design cost and the like.
Description
Technical Field
The invention relates to a high-precision low-temperature drift discrete double-matching constant current source temperature measuring circuit, and belongs to the technical field of temperature measurement.
Background
In order to eliminate the influence of the resistance of the connecting lines on the measured value, this is compensated for in the measuring circuit. At present, a constant current source type thermal resistance temperature measuring circuit used in the instrument industry adopts a single constant current source to supply power, the mode needs compensation of a hardware circuit or a software algorithm to approximately eliminate the influence of lead resistance on a measured value, the influence of lead resistance cannot be absolutely eliminated, the design difficulty is increased, the constant current source type thermal resistance temperature measuring circuit can only be used in the general industrial application field, and the measured value and an actual value have larger deviation and have large influence on the measurement. The double constant current source method is one of three-wire PT100 platinum thermal resistor collection methods, in theory, the double constant current source method can effectively eliminate wire resistance, but the existing double constant current source method is highly dependent on an analog-to-digital conversion chip, in practical application, the expansibility is low, a single analog-to-digital conversion chip can only measure one path of PT100, and when multiple paths of PT100 measurement is needed or other types of analog-to-digital conversion are added, the circuit cannot meet the application.
Disclosure of Invention
The invention aims to solve the technical problems that the existing double-matching constant current source is highly dependent on an analog-to-digital converter and has low signal measurement expansibility, and provides a high-precision low-temperature drift discrete double-matching constant current source temperature measuring circuit.
In order to solve the technical problems, the invention adopts the following technical scheme:
a high-precision low-temperature drift discrete double-matching constant current source temperature measuring circuit is composed of a platinum resistor Rt, a voltage stabilizing chip U1, three double operational amplifiers U2, U3 and U4, an analog-to-digital converter U5, a symmetrical transistor U6, 16 resistors R1-R16 and a capacitor C1, wherein the first resistor R1, the second resistor R2, the third resistor R3 and the platinum resistor Rt form a three-wire platinum thermal resistor PT100, the 2 end of the first resistor R1 is connected with a power supply VCC, the 1 end of the first resistor R1 is connected with the 2 end of the platinum resistor Rt, the 1 end of the platinum resistor Rt is connected with the 2 end of a second resistor R2, and the 1 end of the second resistor R2 is connected with the 2 end of a fourth resistor R4; the 1 end of the fourth resistor R4 is connected with the collector of the first triode Q1 of the symmetrical transistor U6, the base of the first triode Q1 of the symmetrical transistor U6 is connected with the base of the second triode Q2 of the symmetrical transistor U6 and the 1 end of the fifth resistor R5, and the 2 end of the fifth resistor R5 is connected with the power supply VCC; the emitter of the first triode Q1 of the symmetrical transistor U6, the emitter of the second triode Q2 of the symmetrical transistor U6 and the 2 end of the seventh resistor R7 are connected with the reference electrode of the voltage stabilizing chip U1; the 1 end of the seventh resistor R7 is connected with the anode of the voltage stabilizing chip U1 and grounded; the 2 end of the third resistor R3 is connected with the 1 end of the first resistor R1, the 1 end of the third resistor R3 is connected with the 2 end of the sixth resistor R6 and then is connected with the 5 end of the second double-operation amplifier U3, and the 1 end of the sixth resistor R6 is connected with the collector electrode of the second triode Q2 of the symmetrical transistor U6; the 1 end of the second resistor R2 is connected with the 5 end of the first double operational amplifier U2; the end 6 of the first double operational amplifier U2 is connected with the end 1 of the eighth resistor R8 and the end 1 of the ninth resistor R9; the 6 end of the second double operational amplifier U3 is connected with the 2 end of the eighth resistor R8 and the 1 end of the tenth resistor R10; the 2 end of the tenth resistor R10 is connected with the 2 end of the thirteenth resistor R13 and the 7 end of the second double-operational amplifier U3; the 2 end of the ninth resistor R9 is connected with the 2 end of the eleventh resistor R11 and the 7 end of the first double operational amplifier U2, and the 6 end of the third double operational amplifier U4 is connected with the 1 end of the eleventh resistor R11 and the 2 end of the twelfth resistor R12; the 1 end of the twelfth resistor R12 is connected with the 7 end of the third double operational amplifier U4 and the 1 end of the analog-digital converter U5; the 2 end of the fourteenth resistor R14 is grounded; the 1 end of the fourteenth resistor R14 is connected with the 1 end of the thirteenth resistor R13 and the 5 end of the third double operational amplifier U4; the end 6 and the end 2 of the analog-to-digital converter U5 are connected with the end 1 of the capacitor C1 and grounded; the 5 end of the analog-to-digital converter U5 is connected with the 2 end of the capacitor C1 and the power supply VCC; the 3 end of the analog-to-digital converter U5 is connected with the 2 end of the sixteenth resistor R16, and the 4 end of the analog-to-digital converter U5 is connected with the 2 end of the fifteenth resistor R15; the 1 terminal of the fifteenth resistor R15 and the 1 terminal of the sixteenth resistor R16 are connected to the power supply VCC.
Further, the model number of the voltage stabilizing chip U1 is TL431; the model numbers of the first double operational amplifier U2, the second double operational amplifier U3 and the third double operational amplifier U4 are LM358; the model of the analog-digital converter U5 is MCP3421, and the model of the symmetrical transistor U6 is SSM2212.
The beneficial effects of the invention are as follows:
1. the invention adopts a split double-matching constant current source circuit to provide two paths of matched constant current sources for the temperature measuring circuit, and the invention can lead the signal sampling part, the signal amplifying part and the analog-to-digital conversion part to be independent.
2. The invention reduces the number of chips, is convenient for the expansion of the multipath PT100 or the measurement of other analog quantities, and reduces the design cost.
Drawings
Fig. 1 is a schematic circuit diagram of the present invention.
Detailed Description
The invention is described in further detail below with reference to the drawings and examples.
As shown in fig. 1, in the embodiment, a high-precision low-temperature drift discrete dual-matching constant-current source temperature measuring circuit is composed of a platinum resistor Rt, a voltage stabilizing chip U1, three dual operational amplifiers U2, U3 and U4, an analog-to-digital converter U5, a symmetrical transistor U6, 16 resistors R1-R16 and a capacitor C1, wherein the first resistor R1, the second resistor R2, the third resistor R3 and the platinum resistor Rt form a three-wire platinum thermal resistor PT100, the 2 end of the first resistor R1 is connected with a power VCC, the 1 end of the first resistor R1 is connected with the 2 end of the platinum resistor Rt, the 1 end of the platinum resistor Rt is connected with the 2 end of the second resistor R2, and the 1 end of the second resistor R2 is connected with the 2 end of the fourth resistor R4; the 1 end of the fourth resistor R4 is connected with the collector of the first triode Q1 of the symmetrical transistor U6, the base of the first triode Q1 of the symmetrical transistor U6 is connected with the base of the second triode Q2 of the symmetrical transistor U6 and the 1 end of the fifth resistor R5, and the 2 end of the fifth resistor R5 is connected with the power supply VCC; the emitter of the first triode Q1 of the symmetrical transistor U6, the emitter of the second triode Q2 of the symmetrical transistor U6 and the 2 end of the seventh resistor R7 are connected with the reference electrode of the voltage stabilizing chip U1; the 1 end of the seventh resistor R7 is connected with the anode of the voltage stabilizing chip U1 and grounded; the 2 end of the third resistor R3 is connected with the 1 end of the first resistor R1, the 1 end of the third resistor R3 is connected with the 2 end of the sixth resistor R6 and then is connected with the 5 end of the second double-operation amplifier U3, and the 1 end of the sixth resistor R6 is connected with the collector electrode of the second triode Q2 of the symmetrical transistor U6; the 1 end of the second resistor R2 is connected with the 5 end of the first double operational amplifier U2; the end 6 of the first double operational amplifier U2 is connected with the end 1 of the eighth resistor R8 and the end 1 of the ninth resistor R9; the 6 end of the second double operational amplifier U3 is connected with the 2 end of the eighth resistor R8 and the 1 end of the tenth resistor R10; the 2 end of the tenth resistor R10 is connected with the 2 end of the thirteenth resistor R13 and the 7 end of the second double-operational amplifier U3; the 2 end of the ninth resistor R9 is connected with the 2 end of the eleventh resistor R11 and the 7 end of the first double operational amplifier U2, and the 6 end of the third double operational amplifier U4 is connected with the 1 end of the eleventh resistor R11 and the 2 end of the twelfth resistor R12; the 1 end of the twelfth resistor R12 is connected with the 7 end of the third double operational amplifier U4 and the 1 end of the analog-digital converter U5; the 2 end of the fourteenth resistor R14 is grounded; the 1 end of the fourteenth resistor R14 is connected with the 1 end of the thirteenth resistor R13 and the 5 end of the third double operational amplifier U4; the end 6 and the end 2 of the analog-to-digital converter U5 are connected with the end 1 of the capacitor C1 and grounded; the 5 end of the analog-to-digital converter U5 is connected with the 2 end of the capacitor C1 and the power supply VCC; the 3 end of the analog-to-digital converter U5 is connected with the 2 end of the sixteenth resistor R16, and the 4 end of the analog-to-digital converter U5 is connected with the 2 end of the fifteenth resistor R15; the 1 terminal of the fifteenth resistor R15 and the 1 terminal of the sixteenth resistor R16 are connected to the power supply VCC. The first, second and third resistors R1, R2, R3 are resistances of wires.
The model of the voltage stabilizing chip U1 is TL431; the model numbers of the first double operational amplifier U2, the second double operational amplifier U3 and the third double operational amplifier U4 are LM358; the model of the analog-digital converter U5 is MCP3421, and the model of the symmetrical transistor U6 is SSM2212.
The working principle of the invention is as follows:
the double-matching constant current source temperature measuring part (consisting of R1, rt, R2, R4, R5, R3, R6, R7, U1 and U6) inputs the acquired differential voltage into the differential amplifier (consisting of U2, U3, U4, R8, R9, R10, R11, R12 and R13), the differential amplifier amplifies the signal and sends the signal to the analog-to-digital converter for converting the analog quantity into the digital quantity, the first triode Q1 of the symmetrical transistor U6 and the second triode Q2 of the symmetrical transistor U6 are double-channel NPN triode pairs, namely the hfe1 value and the hfe2 value of the two triodes tend to be consistent, and the asymmetry of the transistors can be greatly reduced. When ib1=ib2, the differences in collector currents I1 and I2 flowing through Q1 and Q2 are extremely small.
Formula derivation:
I1+I2＝Vref/R7；I1＝I2；
I1＝I2＝Vref/R7/2；
V1＝Vcc-I1*(Rt+R2)-(I1+I2)*R1；V2＝VCC-(I1+I2)*R1-I2*R3；
since PT100 wire resistance r1=r2=r3; operational amplifier gain: a=1+2×r9/R8;
Vo＝A(V2-V1)＝A(I1*Rt)；
thus rt=vo/a/i1=2×vo×r7/a/Vref; the measured temperature can be obtained from Rt.
Claims (2)
1. The high-precision low-temperature drift discrete double-matching constant current source temperature measuring circuit is characterized by comprising a platinum resistor Rt, a voltage stabilizing chip U1, three double operational amplifiers U2, U3 and U4, an analog-to-digital converter U5, symmetrical transistors U6, 16 resistors R1-R16 and a capacitor C1, wherein the first resistor R1, the second resistor R1, the third resistor R2, the R3 and the platinum resistor Rt form a three-wire platinum thermal resistor PT100, the 2 end of the first resistor R1 is connected with a power supply VCC, the 1 end of the first resistor R1 is connected with the 2 end of the platinum resistor Rt, the 1 end of the platinum resistor Rt is connected with the 2 end of a second resistor R2, and the 1 end of the second resistor R2 is connected with the 2 end of a fourth resistor R4; the 1 end of the fourth resistor R4 is connected with the collector of the first triode Q1 of the symmetrical transistor U6, the base of the first triode Q1 of the symmetrical transistor U6 is connected with the base of the second triode Q2 of the symmetrical transistor U6, the 1 end of the fifth resistor R5 and the cathode of the voltage stabilizing chip U1, and the 2 end of the fifth resistor R5 is connected with the power supply VCC; the emitter of the first triode Q1 of the symmetrical transistor U6, the emitter of the second triode Q2 of the symmetrical transistor U6 and the 2 end of the seventh resistor R7 are connected with the reference electrode of the voltage stabilizing chip U1; the 1 end of the seventh resistor R7 is connected with the anode of the voltage stabilizing chip U1 and grounded; the 2 end of the third resistor R3 is connected with the 1 end of the first resistor R1, the 1 end of the third resistor R3 is connected with the 2 end of the sixth resistor R6 and then is connected with the non-inverting input end of the second double-operational amplifier U3, and the 1 end of the sixth resistor R6 is connected with the collector electrode of the second triode Q2 of the symmetrical transistor U6; the 1 end of the second resistor R2 is connected with the non-inverting input end of the first double operational amplifier U2; the inverting input end of the first double operational amplifier U2 is connected with the 1 end of the eighth resistor R8 and the 1 end of the ninth resistor R9; the inverting input end of the second double-operational amplifier U3 is connected with the 2 end of the eighth resistor R8 and the 1 end of the tenth resistor R10; the 2 end of the tenth resistor R10 is connected with the 2 end of the thirteenth resistor R13 and the output end of the second double-operational amplifier U3; the 2 end of the ninth resistor R9 is connected with the 2 end of the eleventh resistor R11 and the output end of the first double operational amplifier U2, and the inverting input end of the third double operational amplifier U4 is connected with the 1 end of the eleventh resistor R11 and the 2 end of the twelfth resistor R12; the 1 end of the twelfth resistor R12 is connected with the output end of the third double operational amplifier U4 and the VIN+ end of the analog-to-digital converter U5; the 2 end of the fourteenth resistor R14 is grounded; the 1 end of the fourteenth resistor R14 is connected with the 1 end of the thirteenth resistor R13 and the non-inverting input end of the third double operational amplifier U4; the VIN end and the VSS end of the analog-to-digital converter U5 are connected with the 1 end of the capacitor C1 and grounded; the VCC end of the analog-to-digital converter U5 is connected with the 2 end of the capacitor C1 and the power supply VCC; the SCL end of the analog-to-digital converter U5 is connected with the 2 end of the sixteenth resistor R16, and the SDA end of the analog-to-digital converter U5 is connected with the 2 end of the fifteenth resistor R15; the 1 end of the fifteenth resistor R15 and the 1 end of the sixteenth resistor R16 are connected with a power supply VCC, and the model number of the voltage stabilizing chip U1 is TL431.
2. The high-precision low-temperature drift discrete double-matching constant current source temperature measurement circuit according to claim 1, wherein the temperature measurement circuit is characterized in that: the model numbers of the first double operational amplifier U2, the second double operational amplifier U3 and the third double operational amplifier U4 are LM358; the model of the analog-digital converter U5 is MCP3421, and the model of the symmetrical transistor U6 is SSM2212.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910793766.2A CN110440945B (en) | 2019-08-27 | 2019-08-27 | High-precision low-temperature drift discrete type double-matching constant current source temperature measuring circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910793766.2A CN110440945B (en) | 2019-08-27 | 2019-08-27 | High-precision low-temperature drift discrete type double-matching constant current source temperature measuring circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110440945A CN110440945A (en) | 2019-11-12 |
| CN110440945B true CN110440945B (en) | 2024-02-20 |
Family
ID=68437692
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910793766.2A Active CN110440945B (en) | 2019-08-27 | 2019-08-27 | High-precision low-temperature drift discrete type double-matching constant current source temperature measuring circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110440945B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113433999B (en) * | 2021-07-12 | 2022-09-23 | 北京航空航天大学 | High-precision low-noise program-controlled current source for magnetic field generation |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2503515A1 (en) * | 1974-01-30 | 1975-07-31 | Karl Gustav Erik Berg | Resistance measurement circuit - eliminates the effect of resistance of wires connecting measured with a measuring circuit |
| CN87209805U (en) * | 1987-07-07 | 1988-12-14 | 北京自动化仪表二厂 | Multiways digital temp. display instrument |
| CN2174690Y (en) * | 1993-10-23 | 1994-08-17 | 湘潭市瑞桑信息技术公司 | Intelligent calorimeter |
| CN202648827U (en) * | 2012-05-31 | 2013-01-02 | 北京三一自动化技术有限责任公司 | Temperature measurement circuit, temperature acquisition system, frequency converter and temperature transmitter |
| CN203837836U (en) * | 2014-04-25 | 2014-09-17 | 厦门亨立德电子有限公司 | High precision low temperature ticket thermal resistance temperature measuring circuit |
| CN204855009U (en) * | 2015-05-12 | 2015-12-09 | 深圳市四方电气技术有限公司 | Temperature detection circuit based on platinum thermal resistance |
| CN204988537U (en) * | 2015-04-21 | 2016-01-20 | 珠海格力电器股份有限公司 | Temperature transmitter |
| CN105784176A (en) * | 2016-05-25 | 2016-07-20 | 北京先驱威锋技术开发公司 | Temperature measuring system and method based on platinum resistor |
| CN107505061A (en) * | 2017-04-14 | 2017-12-22 | 北京机械设备研究所 | A kind of platinum resistance temperature measuring device in double-current source |
| CN211013290U (en) * | 2019-08-27 | 2020-07-14 | 太原合创自动化有限公司 | High-precision low-temperature-drift discrete double-matching constant-current source temperature measurement circuit |
-
2019
- 2019-08-27 CN CN201910793766.2A patent/CN110440945B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2503515A1 (en) * | 1974-01-30 | 1975-07-31 | Karl Gustav Erik Berg | Resistance measurement circuit - eliminates the effect of resistance of wires connecting measured with a measuring circuit |
| CN87209805U (en) * | 1987-07-07 | 1988-12-14 | 北京自动化仪表二厂 | Multiways digital temp. display instrument |
| CN2174690Y (en) * | 1993-10-23 | 1994-08-17 | 湘潭市瑞桑信息技术公司 | Intelligent calorimeter |
| CN202648827U (en) * | 2012-05-31 | 2013-01-02 | 北京三一自动化技术有限责任公司 | Temperature measurement circuit, temperature acquisition system, frequency converter and temperature transmitter |
| CN203837836U (en) * | 2014-04-25 | 2014-09-17 | 厦门亨立德电子有限公司 | High precision low temperature ticket thermal resistance temperature measuring circuit |
| CN204988537U (en) * | 2015-04-21 | 2016-01-20 | 珠海格力电器股份有限公司 | Temperature transmitter |
| CN204855009U (en) * | 2015-05-12 | 2015-12-09 | 深圳市四方电气技术有限公司 | Temperature detection circuit based on platinum thermal resistance |
| CN105784176A (en) * | 2016-05-25 | 2016-07-20 | 北京先驱威锋技术开发公司 | Temperature measuring system and method based on platinum resistor |
| CN107505061A (en) * | 2017-04-14 | 2017-12-22 | 北京机械设备研究所 | A kind of platinum resistance temperature measuring device in double-current source |
| CN211013290U (en) * | 2019-08-27 | 2020-07-14 | 太原合创自动化有限公司 | High-precision low-temperature-drift discrete double-matching constant-current source temperature measurement circuit |
Non-Patent Citations (1)
| Title |
|---|
| 基于恒流桥的高精度温度测量系统;郭世平;张荣福;郁浩;程金光;;电子科技;20151115(第11期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110440945A (en) | 2019-11-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108225588B (en) | Temperature sensor and temperature detection method | |
| CN106989847B (en) | Error correcting method in system of Pt-resistance | |
| CN105784176B (en) | A kind of temperature measurement system and measuring method based on platinum resistance | |
| CN204085729U (en) | A kind of high-precision platinum resistance temperature measurement mechanism | |
| CN109714054B (en) | Constant current source circuit and ternary discrete I/F analog-to-digital conversion circuit with same | |
| CN114895231B (en) | High-end voltage differential sampling calibration system and method | |
| CN107543626B (en) | High-precision temperature sensor without calibration | |
| CN110440945B (en) | High-precision low-temperature drift discrete type double-matching constant current source temperature measuring circuit | |
| CN204855009U (en) | Temperature detection circuit based on platinum thermal resistance | |
| CN211013290U (en) | High-precision low-temperature-drift discrete double-matching constant-current source temperature measurement circuit | |
| CN104764539A (en) | Universal and output-adjustable thermistor linear compensation circuit based on audion | |
| CN109580025A (en) | A kind of wide scope platinum resistance temperature sample circuit | |
| CN110108380A (en) | A kind of precise temperature measurement system applied to biphenyl heater box in weaving elasticizer | |
| CN106873702A (en) | A kind of compensation circuit of piezoresistive pressure sensor | |
| CN109540313A (en) | A kind of linear temperature measurement circuit based on silicon-based diode and NTC thermistor | |
| CN203965060U (en) | A kind of temperature sensor circuit based on reference source | |
| CN211347141U (en) | Four-wire system temperature measuring device with linear compensation | |
| CN113589046A (en) | High-precision resistance signal acquisition circuit applied to aviation electromechanical products | |
| CN112698066A (en) | Acquisition and measurement circuit for temperature compensation based on thermistor | |
| CN108037790B (en) | A kind of platinum resistance signal acquisition debug circuit based on double constant-current sources | |
| CN220853923U (en) | Constant-current excited three-wire platinum resistor temperature measuring circuit | |
| CN219738060U (en) | uA level high-precision constant current source system | |
| CN206488792U (en) | A kind of high-precision single arm bridge circuit of sketch-based user interface method | |
| CN207335903U (en) | A kind of system for detecting temperature | |
| CN219348003U (en) | Three-wire PT100 temperature measurement circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |