CN216160039U - Thermocouple temperature measurement circuit - Google Patents
Thermocouple temperature measurement circuit Download PDFInfo
- Publication number
- CN216160039U CN216160039U CN202120599556.2U CN202120599556U CN216160039U CN 216160039 U CN216160039 U CN 216160039U CN 202120599556 U CN202120599556 U CN 202120599556U CN 216160039 U CN216160039 U CN 216160039U
- Authority
- CN
- China
- Prior art keywords
- module
- signal
- capacitor
- power supply
- selection
- 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
Images
Landscapes
- Measuring Temperature Or Quantity Of Heat (AREA)
Abstract
The utility model provides a thermocouple temperature measuring circuit, comprising: the device comprises a detection module, a first signal selection module, a signal processing module, a second signal selection module, an AD conversion module, a reference voltage module and a processor, wherein the signal processing module comprises a signal amplification unit and a negative power supply unit; the utility model uses the signal processing module with high integration and high precision, avoids the error and external interference caused by the operational amplifier circuit, does not need to additionally perform cold end compensation, and avoids the error caused by the cold end compensation circuit; the first signal selection module is adopted at the rear end of the detection module, and a plurality of thermocouples can be connected under the condition of multipoint temperature measurement, so that the applicability is greatly improved; in addition, a high-precision reference voltage module is adopted to provide reference voltage for the signal processing module, the second signal selection module and the AD conversion module, so that the measurement precision is improved, errors caused by circuit offset can be offset, and better economic benefit and social benefit are achieved.
Description
Technical Field
The utility model relates to the technical field of temperature detection, in particular to a thermocouple temperature measuring circuit.
Background
The thermocouple is one of the most common temperature detection elements in the industry, and is not influenced by an intermediate medium because the thermocouple can be directly contacted with a measured object; the measuring range is wide, and the common thermocouple can continuously measure at the temperature of between-50 and +1300 ℃; the device has the advantages of high measurement precision, simple structure, convenient use and the like, and is widely applied to various fields including refrigeration, heating, chemical engineering, metallurgy and machinery.
The existing thermocouple temperature measuring circuit is generally composed of an operational amplifier, and comprises a signal amplifying circuit, a zero point adjusting circuit, a cold end compensating circuit and an AD conversion circuit.
The circuit composed of operational amplifiers has the following disadvantages:
1. the product cannot realize the uniformity of measurement accuracy, and the zero point and cold end compensation resistance value need to be manually adjusted when the product is used;
2. due to the noise of the operational amplifier, zero drift and errors among components, automatic calibration of the zero drift cannot be performed after the errors are generated, and certain drift can be generated after long-term use, so that the measurement precision is reduced;
3. in the case of multi-channel temperature measurement, each input needs an amplifying circuit, which increases the manufacturing cost and increases the maintenance cost.
Disclosure of Invention
In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a thermocouple temperature measurement circuit, which is used to solve the problems in the prior art that zero point and cold end compensation resistance value need to be manually adjusted, a certain drift is generated after long-term use, so that the measurement accuracy is reduced, and the manufacturing and maintenance costs are increased.
To achieve the above and other related objects, the present invention provides a thermocouple temperature measuring circuit, including: the device comprises a detection module, a first signal selection module, a signal processing module, a second signal selection module, an AD conversion module, a reference voltage module and a processor, wherein the signal processing module comprises a signal amplification unit and a negative power supply unit;
the input end of the detection module is connected with a plurality of externally connected thermocouples, the output end of the detection module is connected with the input end of the first signal selection module, the output end of the first signal selection module is connected with the input end of the signal amplification unit,
the input end of the negative power supply unit is connected with the output end of the reference voltage module, the output end of the negative power supply unit is connected with the input end of the signal amplification unit, the output ends of the signal amplification unit, the negative power supply unit and the reference voltage module are respectively connected with the input end of the second signal selection module, the output end of the second signal selection module is connected with the input end of the AD conversion module, the input end of the AD conversion module is also connected with the output end of the reference voltage module, and the output end of the AD conversion module is connected with the input end of the processor,
the processor is also connected with the first signal selection module, the second signal selection module and the control end of the AD conversion module respectively.
In an embodiment of the present invention, the detection module includes a plurality of temperature detection units, an input end of each of the temperature detection units is connected to a corresponding thermocouple, and the temperature detection units include a connection piece J1, a plurality of resistors and a plurality of capacitors;
the input end of the connecting piece J1 is connected with the thermocouple, the first pin of the output end is respectively connected with one end of a resistor R2, a capacitor C2 and a resistor R3, the second pin is respectively connected with one end of a resistor R1 and one end of a capacitor C1, the other ends of the resistor R2, the capacitor C2 and the capacitor C1 are grounded, the other end of a resistor R1 is connected with one end of the capacitor C3, the other end of the resistor R3 is connected with the other end of the capacitor C3, and the two ends of the capacitor C3 are respectively connected with the input end of the first signal selection module.
In an embodiment of the present invention, the first signal selection module includes a first selection unit and a second selection unit;
one end of a capacitor C3 of each temperature detection unit is connected with the input end of the first selection unit, and the other end of a capacitor C3 is connected with the input end of the second selection unit;
the control ends of the first selection unit and the second selection unit are connected with the processor, and the output end of the first selection unit and the output end of the second selection unit are connected with the input end of the signal amplification unit.
In an embodiment of the present invention, the first selecting unit includes a multiplexing switch U1, and the second selecting unit includes a multiplexing switch U2;
three selection ends of a multi-way selection switch U1 and a multi-way selection switch U2 are connected with the processor, a signal input end of a multi-way selection switch U1 is connected with one end of a capacitor C3 of each temperature detection unit, a signal input end of a multi-way selection switch U2 is connected with the other end of a capacitor C3 of each temperature detection unit,
the signal output ends of the multi-way selection switch U1 and the multi-way selection switch U2 are connected with the input end of the signal amplification unit,
the positive power supply ends of the multi-way selection switch U1 and the multi-way selection switch U2 are connected with a positive power supply V, and the negative power supply end, the grounding end and the enabling end are all grounded.
In an embodiment of the utility model, the signal amplifying unit includes an operational amplifier U3, a resistor R4, and a capacitor C4;
the non-inverting input end of the operational amplifier U3 is connected with the output end of the first selection unit, the inverting input end of the operational amplifier U3 is connected with the output end of the second selection unit, the detection pin and the output end of the second selection unit are connected with one end of a resistor R4, the other end of the resistor R4 is connected with one end of a capacitor C4 and one input end of the second signal selection module, the other end of the capacitor C4 is connected with a reference voltage end, the other input end of the second signal selection module and the output end of the negative power supply unit, the positive power supply end of the operational amplifier U3 is connected with a positive power supply V, and the negative power supply end is grounded.
In an embodiment of the present invention, the negative power supply unit includes an operational amplifier U4, a non-inverting input terminal of the operational amplifier U4 is connected to the output terminal of the reference voltage module, an inverting input terminal of the operational amplifier U4 is connected to the input terminal of the signal amplification unit after being connected to the output terminal, a capacitor C5 is connected in series between the output terminal and the negative power supply terminal, the positive power supply terminal is connected to the positive power supply V, and the negative power supply terminal is grounded.
In an embodiment of the utility model, the reference voltage module includes a reference source chip U7, a capacitor C8, and a capacitor C9, a power input end of the reference source chip U7 is connected to the positive power supply V, a ground end is grounded, a power output end is respectively connected to a positive terminal of the capacitor C8 and one end of the capacitor C9, a negative terminal of the capacitor C8 and the other end of the capacitor C9 are grounded, and the power output ends are further respectively connected to the negative power supply unit, the second signal selection module, and the input end of the AD conversion module.
In an embodiment of the present invention, the second signal selection module includes a multi-way selection switch U2;
two selection ends of the multi-way selection switch U1 are connected with the processor, a first group of signal input ends are respectively connected with the reference voltage module and the output end of the negative power supply unit, a second group of signal input ends are respectively connected with the signal amplification unit and the output end of the negative power supply unit, a third group of signal input ends are connected with the output end of the negative power supply unit,
two signal output ends of the multi-way selection switch U2 are connected with the input end of the AD conversion module,
the positive power supply end of the multi-way selection switch U2 is connected with a positive power supply V, and the negative power supply end, the grounding end and the enabling end of the multi-way selection switch U2 are all grounded.
In an embodiment of the utility model, the AD conversion module includes an AD conversion chip U6, a capacitor C6, a capacitor C7, and a crystal oscillator Y1;
one end of a capacitor C6 and one end of a capacitor C7 are grounded, the other end of a capacitor C6 is respectively connected with one end of a crystal oscillator Y1 and a clock input end of an AD conversion chip U6, the other end of a capacitor C7 is respectively connected with the other end of a crystal oscillator Y1 and a crystal oscillator driving end of an AD conversion chip U6, a reference voltage end of the AD conversion chip U6 is connected with an output end of the reference voltage module, two analog signal input ends of the AD conversion chip U6 are respectively connected with two signal output ends of the first signal selection module, a digital power supply end and an analog power supply end of the AD conversion chip U6 are respectively connected with a positive power supply V, a digital ground end and an analog ground end of the AD conversion chip U6 are respectively grounded, the chip selection end, the serial data input end, the serial data output end, the synchronous pulse input end and the data ready signal output end of the AD conversion chip U6 are respectively connected with corresponding pins of the processor.
As mentioned above, the thermocouple temperature measuring circuit of the utility model has the following beneficial effects: the high-integration and high-precision signal processing module is used, so that errors and external interference caused by an operational amplifier circuit are avoided, cold end compensation is not required additionally, and errors caused by a cold end compensation circuit are avoided; the first signal selection module is adopted at the rear end of the detection module, and a plurality of thermocouples can be connected under the condition of multipoint temperature measurement, so that the applicability is greatly improved; in addition, a high-precision reference voltage module is adopted to provide reference voltage for the signal processing module, the second signal selection module and the AD conversion module, so that the measurement precision is improved, and errors caused by circuit offset can be offset; the utility model has reasonable design, can detect multipoint temperature, has high precision of the detected temperature and has better economic benefit and social benefit.
Drawings
Fig. 1 shows a block diagram of the overall structure disclosed in the embodiment of the present invention.
Fig. 2 is a schematic wiring diagram of the temperature detection unit disclosed in the embodiment of the present invention.
Fig. 3 is a schematic wiring diagram of the first selecting unit disclosed in the embodiment of the present invention.
Fig. 4 is a schematic wiring diagram of a second selecting unit disclosed in the embodiment of the present invention.
Fig. 5 is a schematic wiring diagram of the signal amplifying unit disclosed in the embodiment of the present invention.
Fig. 6 is a schematic wiring diagram of the negative power supply unit disclosed in the embodiment of the present invention.
Fig. 7 is a schematic wiring diagram of the second signal selection module disclosed in the embodiment of the present invention.
Fig. 8 is a schematic wiring diagram of the reference voltage module disclosed in the embodiment of the present invention.
Fig. 9 is a schematic wiring diagram of the AD conversion module disclosed in the embodiment of the present invention.
Detailed Description
The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The utility model is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention. It is to be noted that the features in the following embodiments and examples may be combined with each other without conflict.
It should be noted that the drawings provided in the following embodiments are only for illustrating the basic idea of the present invention, and the drawings only show the components related to the present invention rather than the number, shape and size of the components in practical implementation, and the type, quantity and proportion of the components in practical implementation can be changed freely, and the layout of the components can be more complicated.
Referring to fig. 1, the present invention provides a thermocouple temperature measuring circuit, including: the device comprises a detection module, a first signal selection module, a signal processing module, a second signal selection module, an AD conversion module, a reference voltage module and a processor.
The detection module comprises a plurality of temperature detection units, the input end of each temperature detection unit is respectively connected with the corresponding thermocouple, and the output end of each temperature detection unit is connected with the input end of the first signal selection module.
Referring to fig. 2, the temperature detecting unit includes a connecting member J1, a plurality of resistors and a plurality of capacitors; the connection J1 is a thermocouple input interface, the first pin of the connection J1 is connected to the resistor R2, and the resistor R2 is a pull-down resistor for detecting whether the thermocouple is connected. The detection signal of the thermocouple is filtered by the capacitor C1 and the capacitor C2 and then is input into the input end of the first signal selection module through the capacitor C3.
Referring to fig. 1, the first signal selection module includes a first selection unit and a second selection unit.
Referring to fig. 3 and 4, the first selection unit includes a multi-way selection switch U1, the second selection unit includes a multi-way selection switch U2, in the present embodiment, the models selected by the multi-way selection switch U1 and the multi-way selection switch U2 are both CD4051, and the following description will be given by taking the multi-way selection switch U1 as an example:
the ninth pin, the tenth pin and the eleventh pin of the multi-way selection switch U1 are three selection ends, and the three selection ends are respectively connected with the processor;
the multiple-way selection switch U1 has eight signal input ends, the thirteenth pin is a signal input end and is connected with one end of the capacitor C3 of any temperature detection unit, and the thirteenth pin of the multiple-way selection switch U2 is connected with the other end of the capacitor C3;
the signal output end of the multi-path selection switch U1 is connected with the input end of the signal processing module;
the positive power supply end of the multi-path selection switch U1 is connected with the positive power supply V, and the negative power supply end, the grounding end and the enabling end are all grounded.
By adopting the scheme, 8 paths of thermocouples can be accessed at most, and which path of thermocouple can be selected and input through the three selection ends, so that the applicability is greatly improved.
Referring to fig. 1, the signal processing module includes a signal amplifying unit and a negative power unit.
Referring to fig. 5, the signal amplifying unit includes an operational amplifier U3, a resistor R4, and a capacitor C4, in this embodiment, the operational amplifier U3 uses an integrated high-precision chip AD8495 dedicated to a thermocouple, and by using this chip, errors and external interference caused by the operational amplifier circuit are avoided, and cold-end compensation is not required, and errors caused by the cold-end compensation circuit are avoided.
The non-inverting input end of the operational amplifier U3 is connected with the output end of the first selection unit, the inverting input end of the operational amplifier U3 is connected with the output end of the second selection unit, and the input temperature detection signal is amplified, filtered by the capacitor C4 and output to the input end of the second signal selection module.
The reference voltage end of the operational amplifier U3 is connected with the output end of the negative power supply unit, and by adopting the scheme, the measuring circuit can measure the temperature below zero when the negative power supply voltage does not exist, so that the circuit is greatly simplified.
Referring to fig. 6, the negative power unit includes an operational amplifier U4, in the present embodiment, the model of the operational amplifier U4 is LM 321.
The operational amplifier U4 constitutes a voltage follower, and the non-inverting input terminal of the operational amplifier U4 is connected with the output terminal of the reference voltage module to output a high-precision voltage.
Referring to fig. 8, the reference voltage module includes a reference source chip U7, a capacitor C8, and a capacitor C9, where the reference source chip U7 converts the input positive power V into a suitable reference voltage, and the reference voltage is filtered by the capacitor C8 and the capacitor C9 to provide a high-precision reference voltage for the negative power unit, the second signal selection module, and the AD conversion module. In this embodiment, the reference source chip U3 has a model REF3012, and outputs a reference voltage of 1.25V.
Referring to fig. 7, the second signal selection module includes a multi-way selection switch U5, and in the present embodiment, the model of the multi-way selection switch U5 is CD 4052.
The ninth pin and the tenth pin of the multiplexer U5 are two selection terminals connected to the output terminal of the processor.
And a fourteenth pin and a fifth pin of the multi-way selection switch U5 are a second group of signal input ends, wherein the fourteenth pin is connected with the output end of the reference voltage module.
And a fifteenth pin and a second pin of the multi-way selection switch U5 are a second group of signal input ends, wherein the fifteenth pin is connected with the output end of the signal amplification unit.
An eleventh pin and a fourth pin of the multiplexer U5 are a fourth set of signal input terminals, wherein the eleventh pin, the fifth pin, the second pin, and the fourth pin are all connected to an output terminal of the negative power unit.
The thirteenth pin and the third pin of the multi-way selector switch U5 are two signal output terminals, and are connected to the input terminal of the AD conversion module.
By adopting the scheme, the output voltages of the reference voltage module and the negative power supply unit are connected to the input end of the second signal selection module, automatic zero calibration can be carried out on the measurement zero voltage and the reference point voltage value as a reference, when the circuit of the detection module has drift errors, the drift amounts of the zero point and the reference point can be calculated by comparing the AD change values of the voltage values, the measurement can be calibrated every time, the circuit measurement drift errors are avoided, manual zero calibration is not needed, time and labor are saved, and meanwhile, human errors are avoided.
Referring to fig. 9, the AD conversion module includes an AD conversion chip U6, a capacitor C6, a capacitor C7, and a crystal oscillator Y1. In this embodiment, the model of the AD conversion chip U2 is CS 1180.
The second pin of the AD conversion chip U6 is a clock input terminal, and the third pin is a driving terminal of the crystal oscillator, wherein the crystal oscillator Y1, the capacitor C6, and the capacitor C7 provide clock signals for the AD conversion chip U6.
The fifth pin of the AD conversion chip U6 is a reference voltage terminal, and is connected to the output terminal of the reference voltage module, so as to ensure that the AD conversion chip U6 outputs a stable digital signal.
The seventh pin and the eighth pin of the AD conversion chip U6 are two analog signal input terminals, and are respectively connected to two signal output terminals of the second signal selection module.
An eleventh pin of the AD conversion chip U6 is a chip select terminal, a twelfth pin is a serial data input terminal, a thirteenth pin is a serial data output terminal, a fourteenth pin is a synchronization pulse input terminal, and a fifteenth pin is a data ready signal output terminal, and is respectively connected to each corresponding pin of the processor.
The tenth pin of the AD conversion chip U6 is an analog power supply end, the sixteenth pin is a digital power supply end, and during actual use, a filter capacitor can be connected between the analog power supply end or the digital power supply end and the ground, so that the working power supply of the chip is more stable.
It should be noted that the model of the processor in this embodiment is MSP430F415, and when in actual use, the model of the processor can be selected according to needs, which is not described herein again.
The thermocouple temperature measuring circuit further comprises a power supply module, wherein the power supply module can be powered by a battery and outputs a positive power supply V to provide working voltage for the whole circuit. In this embodiment, the voltage value of the positive power supply V is 3.6V.
In summary, the thermocouple temperature measurement circuit provided by the utility model uses the signal processing module with high integration and high precision, so that errors and external interference caused by the operational amplifier circuit are avoided, cold end compensation is not required, and errors caused by a cold end compensation circuit are avoided; the first signal selection module is adopted at the rear end of the detection module, and a plurality of thermocouples can be connected under the condition of multipoint temperature measurement, so that the applicability is greatly improved; in addition, a high-precision reference voltage module is adopted to provide reference voltage for the signal processing module, the second signal selection module and the AD conversion module, so that the measurement precision is improved, and errors caused by circuit offset can be offset; the utility model has reasonable design, can detect multipoint temperature, has high precision of the detected temperature and has better economic benefit and social benefit. Therefore, the utility model effectively overcomes various defects in the prior art and has high industrial utilization value.
The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the utility model. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.
Claims (9)
1. A thermocouple thermometry circuit, comprising: the device comprises a detection module, a first signal selection module, a signal processing module, a second signal selection module, an AD conversion module, a reference voltage module and a processor, wherein the signal processing module comprises a signal amplification unit and a negative power supply unit;
the input end of the detection module is connected with a plurality of externally connected thermocouples, the output end of the detection module is connected with the input end of the first signal selection module, the output end of the first signal selection module is connected with the input end of the signal amplification unit,
the input end of the negative power supply unit is connected with the output end of the reference voltage module, the output end of the negative power supply unit is connected with the input end of the signal amplification unit, the output ends of the signal amplification unit, the negative power supply unit and the reference voltage module are respectively connected with the input end of the second signal selection module, the output end of the second signal selection module is connected with the input end of the AD conversion module, the input end of the AD conversion module is also connected with the output end of the reference voltage module, and the output end of the AD conversion module is connected with the input end of the processor,
the processor is also connected with the first signal selection module, the second signal selection module and the control end of the AD conversion module respectively.
2. The thermocouple temperature measurement circuit according to claim 1, wherein: the detection module comprises a plurality of temperature detection units, the input end of each temperature detection unit is respectively connected with a corresponding thermocouple, and each temperature detection unit comprises a connecting piece J1, a plurality of resistors and a plurality of capacitors;
the input end of the connecting piece J1 is connected with the thermocouple, the first pin of the output end is respectively connected with one end of a resistor R2, a capacitor C2 and a resistor R3, the second pin is respectively connected with one end of a resistor R1 and one end of a capacitor C1, the other ends of the resistor R2, the capacitor C2 and the capacitor C1 are grounded, the other end of a resistor R1 is connected with one end of the capacitor C3, the other end of the resistor R3 is connected with the other end of the capacitor C3, and the two ends of the capacitor C3 are respectively connected with the input end of the first signal selection module.
3. The thermocouple temperature measurement circuit according to claim 2, wherein: the first signal selection module comprises a first selection unit and a second selection unit;
one end of a capacitor C3 of each temperature detection unit is connected with the input end of the first selection unit, and the other end of a capacitor C3 is connected with the input end of the second selection unit;
the control ends of the first selection unit and the second selection unit are connected with the processor, and the output end of the first selection unit and the output end of the second selection unit are connected with the input end of the signal amplification unit.
4. The thermocouple temperature measurement circuit according to claim 3, wherein the first selection unit comprises a multiplexing switch U1, and the second selection unit comprises a multiplexing switch U2;
three selection ends of a multi-way selection switch U1 and a multi-way selection switch U2 are connected with the processor, a signal input end of a multi-way selection switch U1 is connected with one end of a capacitor C3 of each temperature detection unit, a signal input end of a multi-way selection switch U2 is connected with the other end of a capacitor C3 of each temperature detection unit, signal output ends of a multi-way selection switch U1 and a multi-way selection switch U2 are connected with the input end of the signal amplification unit,
the positive power supply ends of the multi-way selection switch U1 and the multi-way selection switch U2 are connected with a positive power supply V, and the negative power supply end, the grounding end and the enabling end are all grounded.
5. The thermocouple temperature measurement circuit according to claim 3, wherein: the signal amplification unit comprises an operational amplifier U3, a resistor R4 and a capacitor C4;
the non-inverting input end of the operational amplifier U3 is connected with the output end of the first selection unit, the inverting input end of the operational amplifier U3 is connected with the output end of the second selection unit, the detection pin and the output end of the second selection unit are connected with one end of a resistor R4, the other end of the resistor R4 is connected with one end of a capacitor C4 and one input end of the second signal selection module, the other end of the capacitor C4 is connected with a reference voltage end, the other input end of the second signal selection module and the output end of the negative power supply unit, the positive power supply end of the operational amplifier U3 is connected with a positive power supply V, and the negative power supply end is grounded.
6. The thermocouple temperature measurement circuit according to claim 1, wherein: the negative power supply unit comprises an operational amplifier U4, the non-inverting input end of the operational amplifier U4 is connected with the output end of the reference voltage module, the inverting input end of the operational amplifier U4 is connected with the input end of the signal amplification unit after being connected with the output end, a capacitor C5 is connected between the output end and the negative power supply end in series, the positive power supply end is connected with a positive power supply V, and the negative power supply end is grounded.
7. The thermocouple temperature measurement circuit according to claim 1, wherein: the reference voltage module comprises a reference source chip U7, a capacitor C8 and a capacitor C9, the power input end of the reference source chip U7 is connected with a positive power supply V, the grounding end of the reference source chip U7 is grounded, the power output end of the reference source chip U7 is connected with the positive end of the capacitor C8 and one end of the capacitor C9 respectively, the negative end of the capacitor C8 and the other end of the capacitor C9 are grounded, and the power output end of the reference source chip U3526 is further connected with the negative power supply unit, the second signal selection module and the input end of the AD conversion module respectively.
8. The thermocouple temperature measurement circuit according to claim 1, wherein: the second signal selection module comprises a multi-way selection switch U2;
two selection ends of the multi-way selection switch U1 are connected with the processor, a first group of signal input ends are respectively connected with the reference voltage module and the output end of the negative power supply unit, a second group of signal input ends are respectively connected with the signal amplification unit and the output end of the negative power supply unit, a third group of signal input ends are connected with the output end of the negative power supply unit,
two signal output ends of the multi-path selection switch U2 are connected with the input end of the AD conversion module, a positive power supply end of the multi-path selection switch U2 is connected with a positive power supply V, and a negative power supply end, a grounding end and an enabling end of the multi-path selection switch U2 are all grounded.
9. The thermocouple temperature measurement circuit according to claim 1, wherein: the AD conversion module comprises an AD conversion chip U6, a capacitor C6, a capacitor C7 and a crystal oscillator Y1;
one end of a capacitor C6 and one end of a capacitor C7 are grounded, the other end of a capacitor C6 is respectively connected with one end of a crystal oscillator Y1 and a clock input end of an AD conversion chip U6, the other end of a capacitor C7 is respectively connected with the other end of a crystal oscillator Y1 and a crystal oscillator driving end of an AD conversion chip U6, a reference voltage end of the AD conversion chip U6 is connected with an output end of the reference voltage module, two analog signal input ends of the AD conversion chip U6 are respectively connected with two signal output ends of the first signal selection module, a digital power supply end and an analog power supply end of the AD conversion chip U6 are respectively connected with a positive power supply V, a digital ground end and an analog ground end of the AD conversion chip U6 are respectively grounded, the chip selection end, the serial data input end, the serial data output end, the synchronous pulse input end and the data ready signal output end of the AD conversion chip U6 are respectively connected with corresponding pins of the processor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202120599556.2U CN216160039U (en) | 2021-03-24 | 2021-03-24 | Thermocouple temperature measurement circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202120599556.2U CN216160039U (en) | 2021-03-24 | 2021-03-24 | Thermocouple temperature measurement circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN216160039U true CN216160039U (en) | 2022-04-01 |
Family
ID=80834533
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202120599556.2U Active CN216160039U (en) | 2021-03-24 | 2021-03-24 | Thermocouple temperature measurement circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN216160039U (en) |
-
2021
- 2021-03-24 CN CN202120599556.2U patent/CN216160039U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN202075059U (en) | Novel platinum resistor temperature measurement module | |
| CN105628236A (en) | Thermocouple temperature signal acquisition method | |
| CN111121996A (en) | High-precision thermocouple temperature detection system and method | |
| CN216160039U (en) | Thermocouple temperature measurement circuit | |
| CN105277292A (en) | Temperature measurement device | |
| CN202582775U (en) | Temperature measuring circuit | |
| CN110108380B (en) | Be applied to accurate temperature measurement system of diphenyl heating cabinet in weaving elasticizer | |
| CN211652972U (en) | Linear scale ohmmeter based on constant current source | |
| CN103439018B (en) | Temperature difference detector and to temperature, the detection method of the temperature difference | |
| CN202204616U (en) | Switching detection circuit using multiple PT100 thermistors as temperature sensors | |
| CN217112681U (en) | Ammeter circuit compensation module | |
| US4163938A (en) | Calibrating device for control stations and indicators | |
| CN110470409A (en) | The distal temperature measuring system being easily integrated | |
| CN113514168B (en) | Multi-channel temperature sensor testing device | |
| CN210835059U (en) | nA-level current measuring system for test equipment | |
| CN211347141U (en) | Four-wire system temperature measuring device with linear compensation | |
| CN211576401U (en) | Low-impedance temperature sensor | |
| CN110220606B (en) | Temperature measuring device with calibration function and method | |
| CN211504434U (en) | High-precision thermocouple temperature detection system | |
| CN113820029A (en) | PT100 temperature acquisition circuit for acquisition terminal | |
| CN211373868U (en) | High-precision temperature measuring device | |
| CN215064636U (en) | Temperature and pressure measuring circuit | |
| CN219738060U (en) | uA level high-precision constant current source system | |
| CN201497594U (en) | High-precision platinum resistance temperature measuring device | |
| CN221959657U (en) | Signal acquisition circuit for array resistance type pressure sensor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |