CN209541989U - A kind of pressure sensor state detection circuit - Google Patents
A kind of pressure sensor state detection circuit Download PDFInfo
- Publication number
- CN209541989U CN209541989U CN201920122866.8U CN201920122866U CN209541989U CN 209541989 U CN209541989 U CN 209541989U CN 201920122866 U CN201920122866 U CN 201920122866U CN 209541989 U CN209541989 U CN 209541989U
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- resistance
- electrically connected
- chip
- pressure sensor
- operational amplifier
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Abstract
The utility model proposes a kind of pressure sensor state detection circuits, it can inhibit the common mode interferences such as power frequency, electrostatic and electromagnetic coupling in sensor output signal by the way that instrument amplifier is arranged, the signal for exporting sensor reduces measurement error closer to measured value, improves measurement accuracy；By the way that first voltage comparator is arranged; it can detecte whether pressure sensor short trouble occurs; when pressure sensor breaks down; first voltage comparator exports fault-signal and is input into single-chip microcontroller after the conversion of A/D conversion chip; facilitate staff's detection sensor state, and when there is short trouble, the relay on power circuit can also be made to be formed self-locking; play the role of protecting circuit, reduces equipment and run existing security risk；By the way that second voltage comparison circuit is arranged, it can detecte whether pressure sensor open-circuit fault occurs, when there is open-circuit fault, fault-signal can be input in single-chip microcontroller after A/D is converted and be alarmed.
Description
Technical field
The utility model relates to sensor field more particularly to a kind of pressure sensor state detection circuits.
Background technique
Moment sensor can be divided into inductance type, condenser type, Hall-type etc. by working principle；It is distinguished according to used power supply
AC type and once-through type can be divided into again；It is divided into three-wire type and twin wire by work, the power supply of three-wire type and output signal are to separate
, twin wire power supply is shared with signal.When pressure sensor is without differential pressure, electric bridge two-arm equality, when having pressure difference signal, differential pressure letter
It number is added on 4 ceramic varistors, the resistance value of varistor changes with differential pressure, causes electric bridge unbalance, the electricity for exporting it
Rheology.When open circuit, short circuit occur for sensor or route, control terminal can not judge normal signal or sensor event
Barrier, in the prior art by the way that staff is to the working condition of sensor and the performance condition of connection line is analyzed and failure
Diagnosis, practical operating difficulties, and low efficiency, be easy to happen erroneous judgement and caused by final result cannot be as accurately acquiring
Data.Therefore, to solve the above problems, the utility model provides and a kind of facilitates detection and the high pressure sensor of detection accuracy
State detection circuit.
Utility model content
In view of this, the utility model proposes it is a kind of facilitate detection and detection accuracy it is high pressure sensor state inspection
Slowdown monitoring circuit.
The technical solution of the utility model is achieved in that the utility model provides a kind of pressure sensor state inspection
Slowdown monitoring circuit comprising pressure sensor, power supply and single-chip microcontroller further include instrument amplifier, first voltage comparison circuit, the second electricity
Press comparison circuit, the first A/D conversion chip and the 2nd A/D conversion chip；
Power supply, pressure sensor, instrument amplifier, first voltage comparison circuit, the first A/D conversion chip and single-chip microcontroller are suitable
Secondary electric connection, the input terminal of second voltage comparison circuit and the output end of instrument amplifier are electrically connected, and second voltage compares
The output end of circuit and the 2nd A/D conversion chip are electrically connected, and the 2nd A/D conversion chip and single-chip microcontroller are electrically connected.
On the basis of above technical scheme, it is preferred that instrument amplifier includes operational amplifier U5-U7 and resistance R14-
R20；
The noninverting input of operational amplifier U5 and the C point of pressure sensor are electrically connected, and operational amplifier U5's is reversed
Input terminal is electrically connected with one end of resistance R16 and one end of resistance R17 respectively, and the other end of resistance R16 is put with operation respectively
The output end of big device U5 and one end of resistance R14 are electrically connected, the other end of resistance R17 respectively with one end of resistance R18 and fortune
The reverse input end for calculating amplifier U6 is electrically connected, and the noninverting input of operational amplifier U6 and the D point of pressure sensor are electrical
Connection, the other end of resistance R18 are electrically connected with one end of the output end of operational amplifier U6 and resistance R19 respectively, resistance R19
The other end respectively with the noninverting input of one end of resistance R20 and operational amplifier U7 be electrically connected, the other end of resistance R20
Ground connection, the reverse input end of operational amplifier U7 are electrically connected with one end of the other end of resistance R14 and resistance R15 respectively, electricity
The output end of the other end and operational amplifier U7 that hinder R15 is electrically connected.
It is further preferred that first voltage comparison circuit includes LM393 chip, resistance R23, resistance R24, diode D8-
D10, zener diode D11, capacitor C15 and polarized capacitor C14；
3 pins of the output end of operational amplifier U7 and LM393 chip are electrically connected, 2 pins of LM393 chip respectively with
One end of the cathode of voltage-stabiliser tube D11, one end of capacitor C15 and resistance R24 is electrically connected, the anode and electricity of zener diode D11
The other end for holding C15 is grounded, and the other end of resistance R24 is electrically connected with the power supply, 1 pin and diode D10 of LM393 chip
Anode be electrically connected, 3 pins of the cathode of diode D10 and LM393 chip are electrically connected.
It is further preferred that second voltage comparison circuit includes LM393 chip, resistance R25, resistance R26 and resistance R28；
5 pins of LM393 chip are grounded by resistance R28,6 pins of LM393 chip respectively with one end of resistance R26 and
One end of resistance R25 is electrically connected, and the other end of resistance R26 and the output end of operational amplifier U7 are electrically connected, resistance R25's
7 pins of the other end and LM393 chip are electrically connected.
It is further preferred that the first A/D conversion chip and the 2nd A/D conversion chip are ICL7107；
The INHI pin of first A/D conversion chip and 1 pin of LM393 are electrically connected；
The INHI pin of 2nd A/D conversion chip and 7 pins of LM393 are electrically connected.
It is further preferred that single-chip microcontroller is the single-chip microcontroller with I/O mouthfuls.
On the basis of above technical scheme, it is preferred that the first display and second display；
First display and the first A/D conversion chip are electrically connected, and second display electrically connects with the 2nd A/D conversion chip
It connects.
A kind of pressure sensor state detection circuit of the utility model has the advantages that compared with the existing technology
(1) by setting instrument amplifier, the tiny signal that pressure sensor exports is amplified, and inhibit sensor
The common mode interferences such as power frequency, electrostatic and electromagnetic coupling in output signal, the signal for exporting sensor are reduced closer to measured value
Measurement error improves measurement accuracy；
(2) it by setting first voltage comparator, can detecte whether pressure sensor short trouble occurs, passed in pressure
When sensor breaks down, first voltage comparator exports fault-signal into A/D conversion chip, and being converted into single-chip microcontroller can handle
Digital signal, facilitate staff's detection sensor state, and when there is short trouble, first voltage comparator may be used also
So that the relay on power circuit forms self-locking, plays the role of protecting circuit, reduce equipment and run existing security risk；
(3) by setting second voltage comparison circuit, it can detecte whether pressure sensor open-circuit fault occurs, work as appearance
When open-circuit fault, fault-signal can be input in single-chip microcontroller after A/D is converted and be alarmed；
(4) whole device can detecte whether pressure sensor breaks down, and when there is short trouble, protection electricity
Road.
Detailed description of the invention
In order to illustrate the embodiment of the utility model or the technical proposal in the existing technology more clearly, below will be to embodiment
Or attached drawing needed to be used in the description of the prior art is briefly described, it should be apparent that, the accompanying drawings in the following description is only
It is some embodiments of the utility model, for those of ordinary skill in the art, in the premise not made the creative labor
Under, it is also possible to obtain other drawings based on these drawings.
Fig. 1 is a kind of structure chart of pressure sensor state detection circuit of the utility model；
Fig. 2 is a kind of circuit diagram of pressure sensor state detection circuit of the utility model.
Specific embodiment
Below in conjunction with the utility model embodiment, the technical solution in the utility model embodiment is carried out clear
Chu is fully described by, it is clear that and described embodiment is only a part of embodiment of the utility model, rather than all
Embodiment.Based on the embodiment in the utility model, those of ordinary skill in the art are not making creative work
Under the premise of every other embodiment obtained, fall within the protection scope of the utility model.
As shown in Figure 1, a kind of pressure sensor state detection circuit of the utility model comprising pressure sensor, electricity
Source, single-chip microcontroller, the first display, second display, instrument amplifier, detecting circuit, first voltage comparison circuit, second voltage
Comparison circuit, the first A/D conversion chip and the 2nd A/D conversion chip.
Instrument amplifier has very high common-mode rejection ratio and high-gain, low noise and high input impedance, reduces sensing
The common mode interferences such as power frequency, electrostatic and electromagnetic coupling in device output signal.In the present embodiment, instrument amplifier includes: operation
Amplifier U5-U7 and resistance R14-R20；Specifically, the noninverting input of operational amplifier U5 and the C point of pressure sensor are electrical
Connection, the reverse input end of operational amplifier U5 are electrically connected with one end of resistance R16 and one end of resistance R17 respectively, resistance
The other end of R16 is electrically connected with one end of the output end of operational amplifier U5 and resistance R14 respectively, the other end of resistance R17
It is electrically connected respectively with the reverse input end of one end of resistance R18 and operational amplifier U6, the input in the same direction of operational amplifier U6
End is electrically connected with the D point of pressure sensor, the other end of resistance R18 respectively with the output end and resistance of operational amplifier U6
One end of R19 is electrically connected, the input in the same direction with one end of resistance R20 and operational amplifier U7 respectively of the other end of resistance R19
End is electrically connected, the other end of resistance R20 ground connection, the reverse input end of the operational amplifier U7 other end with resistance R14 respectively
It is electrically connected with one end of resistance R15, the other end of resistance R15 and the output end of operational amplifier U7 are electrically connected.Wherein, it transports
The non-inverting input terminal for calculating amplifier U5 and operational amplifier U6 is the differential input terminal of instrument amplifier respectively, therefore instrument is amplified
The input impedance of device is very high, as shown in Fig. 2, instrument amplifier uses symmetric circuit structure, and pressure sensor output signal
It is applied directly on the differential input terminal of instrument amplifier, to ensure that the stronger ability for inhibiting common-mode signal, operation amplifier
The main input impedance of device U5 and operational amplifier U6 and voltage gain are symmetrical, and drift will greatly reduce, and have high input resistance
Anti-, high cmrr is very sensitive to small differential mode voltage, and is suitable for measuring the signal transmitted at a distance, transports
Calculating amplifier U7 is a differential follower in the present embodiment, and gain is approximately 1.Wherein resistance R17 is used to adjust amplification
Multiple, in the present embodiment, resistance R17 are multiturn potentiometers.
First voltage comparison circuit will judge whether pressure sensor goes out by amplified signal compared with normal value
Existing short trouble.As shown in Fig. 2, first voltage comparator includes LM393 chip, resistance R23, resistance R24, diode D8-
D10, zener diode D11, capacitor C15 and polarized capacitor C14；Specifically, the output end of operational amplifier U7 and LM393 core
3 pins of piece are electrically connected, 2 pins of LM393 chip respectively with the cathode of voltage-stabiliser tube D11, one end of capacitor C15 and resistance
One end of R24 is electrically connected, and the anode of zener diode D11 and the other end of capacitor C15 are grounded, the other end of resistance R24
Be electrically connected with the power supply, the anode of 1 pin of LM393 chip and diode D10 are electrically connected, the cathode of diode D10 with
3 pins of LM393 chip are electrically connected.Wherein, pressure sensor output signal send the signal after instrument amplifier amplifies
The non-inverting input terminal of the voltage comparator formed to LM393, the level of non-inverting input terminal are set as 5.1V, by resistance R24 and surely
The DC voltage value of pressure pipe D11 composition is slightly less than the level；When normal operation of sensor, the maximal current magnitude for exporting electric current is
100mA, maximum pressure drop is 150mV on sensor, and output voltage values are 4.5V after instrument amplifier, is transported to after detection
3 feet of LM393,3 foot level are lower than 2 foot voltages, and LM393 exports low level；When there is short circuit in sensor, sensor output
Electric current, voltage increase, and after instrument amplifier amplifies, greater than the inverting input terminal voltage of LM393 chip, LM393 output is high
Level forms the relay on power circuit self-locking.The moment LM393 chip powered in order to prevent is self-locking, increases
Delay circuit is formed by resistance R23, polarized capacitor C14, diode D8 and diode D9, the effect of D9 is after guaranteeing power-off,
Voltage on polarized capacitor C14 can quickly be bled off, to guarantee that the starting voltage of polarized capacitor C14 when being powered again is zero.
Whether second voltage comparison circuit, detection sensor become smaller without operating current or electric current more than normal current range,
If so, output fault-signal.In the present embodiment, as shown in Fig. 2, second voltage comparison circuit includes, including LM393 chip,
Resistance R25, resistance R26 and resistance R28；Specifically, 5 pins of LM393 chip are grounded by resistance R28, the 6 of LM393 chip
Pin is electrically connected with one end of resistance R26 and one end of resistance R25 respectively, the other end and operational amplifier U7 of resistance R26
Output end be electrically connected, 7 pins of the other end of resistance R25 and LM393 chip are electrically connected.When pressure sensor is opened
When the failure of road, sensor output is not really opened a way, but exports several milliamperes of electric current, through instrument amplifier amplification and detection
After circuit detection, be input to 6 pins of LM393, LM393 exports high level, LM393 output signal in A/D conversion chip into
Row conversion, and show.
First A/D conversion chip and the 2nd A/D conversion chip, by the analog-signal transitions of LM393 output at digital signal,
And measurement result is shown by display.In the present embodiment, as shown in Fig. 2, the first A/D conversion chip and the 2nd A/D conversion
Chip is ICL7107.ICL7107 includes 31/2 biproduct parting A/D converter, and input impedance is high, to input signal without declining
Subtract effect；Low noise, temperature drift is small, has good reliability, the service life is long, and can directly drive common-anode LED charactrons, no
It needs separately to add driving element, simplifies machine line, therefore, the present embodiment can also increase the first display and the second display
Device.
Single-chip microcontroller receives the signal of A/D conversion chip conveying, and alarms in pressure sensor failure.At this
In embodiment, as long as the single-chip microcontroller with I/O mouthfuls can apply in the utility model, in the present embodiment, single-chip microcontroller choosing
With AT89c51 single-chip microcontroller.
The foregoing is merely the better embodiments of the utility model, are not intended to limit the utility model, it is all
Within the spirit and principles of the utility model, it is practical new to should be included in this for any modification, equivalent replacement, improvement and so on
Within the protection scope of type.
Claims (7)
1. a kind of pressure sensor state detection circuit comprising pressure sensor, power supply and single-chip microcontroller, it is characterised in that: also
It is converted including instrument amplifier, first voltage comparison circuit, second voltage comparison circuit, the first A/D conversion chip and the 2nd A/D
Chip；
The power supply, pressure sensor, instrument amplifier, first voltage comparison circuit, the first A/D conversion chip and single-chip microcontroller are suitable
Secondary electric connection, the input terminal of second voltage comparison circuit and the output end of instrument amplifier are electrically connected, and second voltage compares
The output end of circuit and the 2nd A/D conversion chip are electrically connected, and the 2nd A/D conversion chip and single-chip microcontroller are electrically connected.
2. a kind of pressure sensor state detection circuit as described in claim 1, it is characterised in that: the instrument amplifier packet
Include operational amplifier U5-U7 and resistance R14-R20；
The noninverting input of the operational amplifier U5 and the C point of pressure sensor are electrically connected, and operational amplifier U5's is reversed
Input terminal is electrically connected with one end of resistance R16 and one end of resistance R17 respectively, and the other end of resistance R16 is put with operation respectively
The output end of big device U5 and one end of resistance R14 are electrically connected, the other end of resistance R17 respectively with one end of resistance R18 and fortune
The reverse input end for calculating amplifier U6 is electrically connected, and the noninverting input of operational amplifier U6 and the D point of pressure sensor are electrical
Connection, the other end of resistance R18 are electrically connected with one end of the output end of operational amplifier U6 and resistance R19 respectively, resistance R19
The other end respectively with the noninverting input of one end of resistance R20 and operational amplifier U7 be electrically connected, the other end of resistance R20
Ground connection, the reverse input end of operational amplifier U7 are electrically connected with one end of the other end of resistance R14 and resistance R15 respectively, electricity
The output end of the other end and operational amplifier U7 that hinder R15 is electrically connected.
3. a kind of pressure sensor state detection circuit as claimed in claim 2, it is characterised in that: the first voltage compares
Circuit includes LM393 chip, resistance R23, resistance R24, diode D8-D10, zener diode D11, capacitor C15 and polarized
Capacitor C14；
3 pins of the output end of the operational amplifier U7 and LM393 chip are electrically connected, 2 pins of LM393 chip respectively with
One end of the cathode of voltage-stabiliser tube D11, one end of capacitor C15 and resistance R24 is electrically connected, the anode and electricity of zener diode D11
The other end for holding C15 is grounded, and the other end of resistance R24 is electrically connected with the power supply, 1 pin and diode D10 of LM393 chip
Anode be electrically connected, 3 pins of the cathode of diode D10 and LM393 chip are electrically connected.
4. a kind of pressure sensor state detection circuit as claimed in claim 2, it is characterised in that: the second voltage compares
Circuit includes LM393 chip, resistance R25, resistance R26 and resistance R28；
5 pins of the LM393 chip are grounded by resistance R28,6 pins of LM393 chip respectively with one end of resistance R26 and
One end of resistance R25 is electrically connected, and the other end of resistance R26 and the output end of operational amplifier U7 are electrically connected, resistance R25's
7 pins of the other end and LM393 chip are electrically connected.
5. a kind of pressure sensor state detection circuit as described in claim 3 or 4, it is characterised in that: the first A/D turns
Changing chip and the 2nd A/D conversion chip is ICL7107；
The INHI pin of the first A/D conversion chip and 1 pin of LM393 are electrically connected；
The INHI pin of the 2nd A/D conversion chip and 7 pins of LM393 are electrically connected.
6. a kind of pressure sensor state detection circuit as claimed in claim 5, it is characterised in that: the single-chip microcontroller be with
I/O mouthfuls of single-chip microcontroller.
7. a kind of pressure sensor state detection circuit as described in claim 1, it is characterised in that: further include the first display
And second display；
First display and the first A/D conversion chip are electrically connected, and second display electrically connects with the 2nd A/D conversion chip
It connects.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920122866.8U CN209541989U (en) | 2019-01-24 | 2019-01-24 | A kind of pressure sensor state detection circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920122866.8U CN209541989U (en) | 2019-01-24 | 2019-01-24 | A kind of pressure sensor state detection circuit |
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| Publication Number | Publication Date |
|---|---|
| CN209541989U true CN209541989U (en) | 2019-10-25 |
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| CN201920122866.8U Expired - Fee Related CN209541989U (en) | 2019-01-24 | 2019-01-24 | A kind of pressure sensor state detection circuit |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111649872A (en) * | 2020-06-11 | 2020-09-11 | 武汉飞恩微电子有限公司 | Pressure sensor device and system with redundancy diagnosis function |
| CN112254875A (en) * | 2020-10-26 | 2021-01-22 | 南通大学 | Circuit and method for judging connection state of bridge sensor |
| CN112881961A (en) * | 2021-01-27 | 2021-06-01 | 江西晶润光学有限公司 | Detection device and method for magnetic sensor |
| CN112924353A (en) * | 2021-01-20 | 2021-06-08 | 北京理工大学 | Filter fault detection circuit, fault detection device and filter |
| CN113311365A (en) * | 2021-06-01 | 2021-08-27 | 深圳市思榕科技有限公司 | Pressure sensor broken string detection circuitry |
| CN113620134A (en) * | 2021-07-26 | 2021-11-09 | 西尼机电（杭州）有限公司 | Embedded diagnostic device for elevator safety component |
| CN114295280A (en) * | 2022-03-09 | 2022-04-08 | 成都凯天电子股份有限公司 | Pressure signal scanning measurement system |
-
2019
- 2019-01-24 CN CN201920122866.8U patent/CN209541989U/en not_active Expired - Fee Related
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111649872A (en) * | 2020-06-11 | 2020-09-11 | 武汉飞恩微电子有限公司 | Pressure sensor device and system with redundancy diagnosis function |
| CN111649872B (en) * | 2020-06-11 | 2022-02-15 | 武汉飞恩微电子有限公司 | Pressure sensor system with redundant diagnostics |
| CN112254875A (en) * | 2020-10-26 | 2021-01-22 | 南通大学 | Circuit and method for judging connection state of bridge sensor |
| CN112254875B (en) * | 2020-10-26 | 2022-03-08 | 南通大学 | Circuit and method for judging connection state of bridge sensor |
| CN112924353B (en) * | 2021-01-20 | 2022-02-11 | 北京理工大学 | Filter fault detection circuit, fault detection device and filter |
| CN112924353A (en) * | 2021-01-20 | 2021-06-08 | 北京理工大学 | Filter fault detection circuit, fault detection device and filter |
| CN112881961A (en) * | 2021-01-27 | 2021-06-01 | 江西晶润光学有限公司 | Detection device and method for magnetic sensor |
| CN112881961B (en) * | 2021-01-27 | 2024-04-09 | 广州得尔塔影像技术有限公司 | Detection device and method of magnetic sensor |
| CN113311365A (en) * | 2021-06-01 | 2021-08-27 | 深圳市思榕科技有限公司 | Pressure sensor broken string detection circuitry |
| CN113620134A (en) * | 2021-07-26 | 2021-11-09 | 西尼机电（杭州）有限公司 | Embedded diagnostic device for elevator safety component |
| CN113620134B (en) * | 2021-07-26 | 2022-11-11 | 西尼机电（杭州）有限公司 | Embedded diagnostic device for elevator safety component |
| CN114295280A (en) * | 2022-03-09 | 2022-04-08 | 成都凯天电子股份有限公司 | Pressure signal scanning measurement system |
| CN114295280B (en) * | 2022-03-09 | 2022-06-07 | 成都凯天电子股份有限公司 | Pressure signal scanning measurement system |
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