CN207249037U - It is a kind of to be used to detect the detection device whether device connection status comes off - Google Patents
It is a kind of to be used to detect the detection device whether device connection status comes off Download PDFInfo
- Publication number
- CN207249037U CN207249037U CN201721153287.7U CN201721153287U CN207249037U CN 207249037 U CN207249037 U CN 207249037U CN 201721153287 U CN201721153287 U CN 201721153287U CN 207249037 U CN207249037 U CN 207249037U
- Authority
- CN
- China
- Prior art keywords
- resistance
- operational amplifier
- connection
- under test
- capacitance
- 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
Landscapes
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
The utility model discloses a kind of detection device whether to come off for detecting device connection status, it is connected with MCU, including interface, bias circuit and operational amplifier circuit；Interface connects device under test and operational amplifier circuit, bias circuit connection operational amplifier circuit and device under test, operational amplifier circuit connection MCU；Interface is used for transmission the detection signal of device under test, and the magnitude of voltage of the detection signal is corresponded to according to the connection status of device under test to be changed；The bias circuit is used to export corresponding biasing voltage signal according to different device under test；The operational amplifier circuit will detect signal compared with biasing voltage signal, and the value correspondence change of output pressure outputs signal to MCU to judge the connection status of device under test.So as to solve the problems, such as that existing detecting devices cannot detect whether device connection status comes off.
Description
Technical field
Electronic technology field is the utility model is related to, it is more particularly to a kind of to be used to detect what whether device connection status came off
Detection device.
Background technology
With development in science and technology, more and more scenes are needed to monitor in real time and detected, and inevitably use various inspections
Survey device.By taking sensor as an example, many sensors are limited by environment and occupation mode, it is necessary to by extended line and control circuit
Plate is attached.So be possible to cause in the case of transport or vibrations sensor connection to come off, and monitoring personnel without
Method directly understands the connection status of sensor at any time.The error in data in collection can be so caused, mistake is provided to monitoring personnel
Information.
It is therefore desirable to the prior art is improved.
Utility model content
In view of in place of above-mentioned the deficiencies in the prior art, it is used to detect device company the purpose of this utility model is to provide one kind
The detection device whether state comes off is connect, is asked with solve that existing detecting devices cannot detect whether device connection status come off
Topic.
In order to achieve the above object, the utility model takes following technical scheme：
It is a kind of to be used to detect the detection device whether device connection status comes off, it is connected with MCU, it includes interface, bias
Circuit and operational amplifier circuit；
The interface is used for transmission the detection signal of device under test, and the magnitude of voltage of the detection signal is according to device under test
Connection status corresponds to change；The bias circuit is used to export corresponding biasing voltage signal according to different device under test；Institute
Signal will be detected with biasing voltage signal compared with by stating operational amplifier circuit, output pressure value correspond to change output signal to MCU with
Judge the connection status of device under test；
The interface connection device under test and operational amplifier circuit, bias circuit connection operational amplifier circuit and device under test, amplifier electricity
Road connects MCU.
Described is used to detect in the detection device whether device connection status comes off, and the device under test is sensor,
Sensor is made of detecting element and compensating element, encapsulation.
It is described to be used to detect in the detection device whether device connection status comes off, the supply pin connection of the interface the
The other end and bias circuit of two power ends, compensating element,；Interface signal pins connection operational amplifier circuit, detecting element one end and
One end of compensating element,；The other end, bias circuit and the ground of the lower margin connecting detection element of interface.
Described is used to detect in the detection device whether device connection status comes off, and the bias circuit includes the first fortune
Calculate amplifier, first resistor, second resistance, 3rd resistor and adjustable resistance；The in-phase input end of first operational amplifier
Connect one end, one end of second resistance and the control terminal of adjustable resistance of first resistor；The other end connection of first resistor is adjustable
One end and second source end of resistance, the other end and ground of the other end connection adjustable resistance of second resistance, the first operation amplifier
Device inverting input connection 3rd resistor one end, the first operational amplifier output terminal connection 3rd resistor the other end and
Operational amplifier circuit, the positive supply foot of the first operational amplifier connect the first power end, the negative supply foot ground connection of the first operational amplifier；
The other end of the first resistor is also connected with the other end of compensating element, and the other end of second resistance is also connected with detecting
The other end of element.
Described is used to detect in the detection device whether device connection status comes off, and the bias circuit further includes first
Capacitance and the second capacitance；First capacitance one end connection adjustable resistance one end and second source end, the first capacitance it is another
One end connects the other end and ground of adjustable resistance, and one end of the second capacitance connects the positive supply foot and first of the first operational amplifier
Power end, the other end ground connection of the second capacitance.
Described is used to detect in the detection device whether device connection status comes off, and the operational amplifier circuit includes the second fortune
Calculate amplifier, the 4th resistance, the 5th resistance, the 6th resistance, the 7th resistance and the 3rd capacitance；Second operational amplifier it is same
One end of phase input terminal the 4th resistance of connection and one end of the 7th resistance, the signal pins of the other end connecting interface of the 4th resistance,
The other end ground connection of 7th resistance, the 3rd capacitance and the 7th resistor coupled in parallel, the inverting input of the second operational amplifier connect the
One end of five resistance and one end of the 6th resistance, the output terminal of the other end the first operational amplifier of connection of the 5th resistance, second
The output terminal of operational amplifier connects the other end and MCU of the 6th resistance.
Described is used to detect in the detection device whether device connection status comes off, and the operational amplifier circuit further includes the 8th
Resistance and the 4th capacitance；One end of 8th resistance connects the output terminal of the second operational amplifier, the other end of the 8th resistance
Connect one end and the MCU of the 4th capacitance, the other end ground connection of the 4th capacitance.
It is provided by the utility model a kind of for detecting the detection whether device connection status comes off compared to the prior art
Device, the detection signal of device under test is transmitted by interface, the magnitude of voltage of the detection signal is according to the connection shape of device under test
State corresponds to change；The bias circuit is used to export corresponding biasing voltage signal according to different device under test；The amplifier
Circuit will detect signal compared with biasing voltage signal, and the value correspondence change of output pressure outputs signal to MCU to judge to treat
Survey the connection status of device.So as to solve the problems, such as that existing detecting devices cannot detect whether device connection status comes off.
Brief description of the drawings
Fig. 1 is the structural frames provided by the utility model for being used to detect the detection device whether device connection status comes off
Figure.
Fig. 2 is the circuit diagram provided by the utility model for being used to detect the detection device whether device connection status comes off.
Embodiment
The utility model offer is a kind of to be used to detect the detection device whether device connection status comes off, and can not only normally be examined
Survey each detection device（Such as sensor）The signal of collection, can also detect whether each detection device comes off or failure.Suitable for instrument
In equipment of the needs such as instruments and meters, transmitter, combustible gas probe by detecting device gathered data.To make the utility model
Purpose, technical solution and effect it is clearer, clear and definite, the embodiment that develops simultaneously referring to the drawings is further detailed to the utility model
Describe in detail bright.It should be appreciated that specific embodiment described herein is not used to limit this practicality only to explain the utility model
It is new.
It is used to detect the detection device whether device connection status comes off referring to Fig. 1, the utility model offer is a kind of, if
Put on the circuit board of the device Hosts such as instrument and meter, transmitter, combustible gas probe, be connected with MCU.The detection device
Corresponding detection voltage is exported according to the connection status of device under test, MCU can determine whether device to be measured according to the size of detection voltage
Whether part comes off.In the specific implementation, a device under test matches a detection device, the detection electricity of all detection device outputs
Pressure, which is transmitted in MCU, to be judged.
The detection device includes interface 10, bias circuit 20 and operational amplifier circuit 30；Interface 10 connects 40 He of device under test
Operational amplifier circuit 30, bias circuit 20 connect operational amplifier circuit 30 and device under test 40, and operational amplifier circuit 30 connects MCU（Model
stm32）.The interface 10 is used for transmission the detection signal of device under test 40.The magnitude of voltage of the detection signal is according to device to be measured
The connection status of part 40 corresponds to change.The bias circuit 20 is used to export corresponding bias voltage according to different device under test
Signal.Picture lower right corner parallel circuit is bias circuit, and carry out configuration normal signal and come off signal voltage zone it is other
Circuit, and composition sensor comes off or failure important component.The operational amplifier circuit 30 will detect signal and bias voltage
Signal is compared, and the value correspondence change of output pressure outputs signal to MCU.MCU can determine whether according to the magnitude of voltage of output signal
Go out the connection status of device under test 40.
It is to be appreciated that the device under test in the present embodiment is by taking sensor as an example.Sensor burns for common catalysis
Sensor, represents the equivalent circuit of catalytic combustion sensor, it includes detecting element 41 and compensation member also referring to Fig. 2,40
Part 42（As temperature-compensating）.The two component encapsulations form catalytic combustion sensor together, for measuring the dense of combustible gas
Degree.
Please continue to refer to Fig. 2, the supply pin VCC connection second sources end VCC2 of the interface 10, compensating element, 42 it is another
One end and bias circuit 20；The signal pins D connections operational amplifier circuit 30 of interface 10, one end of detecting element 41 and compensating element, 42
One end；The other end, bias circuit 20 and the ground of the lower margin GND connecting detections element 41 of interface 10.
Wherein, the detection signal of device under test output is transmitted to operational amplifier circuit 30 by the signal pins D of interface 10, when to be measured
When device 40 comes off, signal pins D is vacant state.Meanwhile detecting element 41 and compensating element, 42 can be equivalent to two resistance, lead to
Cross second source end VCC2 and ground is connected with bias circuit 20.Controlled according to the connection status of detecting element 41 and compensating element, 42
The input signal of bias circuit 20.
The bias circuit 20 include the first operational amplifier U1, first resistor R1, second resistance R2,3rd resistor R3 and
Adjustable resistance RP；One end of the in-phase input end connection first resistor R1 of the first operational amplifier U1, second resistance R2
One end and the control terminal of adjustable resistance RP；One end and second source end of the other end connection adjustable resistance RP of first resistor R1
The other end and ground of the other end connection adjustable resistance RP of VCC2, second resistance R2, the anti-phase input of the first operational amplifier U1
One end of end connection 3rd resistor R3, the other end and amplifier electricity of the output terminal connection 3rd resistor R3 of the first operational amplifier U1
Road 30, the positive supply foot of the first operational amplifier U1 connect the first power end VCC1, the negative supply foot of the first operational amplifier U1
Ground connection.
Wherein, bias circuit 20 exports corresponding magnitude of voltage to match corresponding biased electrical according to different device under test
Pressure.Detecting element 41 and compensating element, 42 are equivalent to two resistance, by the connection on second source end VCC2 and ground, with the first electricity
Hinder R1 and second resistance R2 composition bridge circuits；That is the other end connection second source end VCC2 and compensating element, of first resistor R1
42 other end, the other end connection ground of second resistance R2 and the other end of detecting element 41.When device under test 40 comes off（Detection
Element 41 and compensating element, 42 disconnect）, then the signal pins D of interface 10 is hanging.If compensating element, 42 disconnects but detecting element 41
Normally, then electric bridge loses perseverance, and detection signal is pulled low, the voltage on the in-phase input end of the first operational amplifier U1（That is input letter
Number voltage）Also it is detected element 41 and is pulled down to ground.If compensating element, 42 is normal but detecting element 41 disconnects, electric bridge loses perseverance,
Detection signal is drawn high by second source end VCC2, and the voltage on the in-phase input end of the first operational amplifier U1 is also by compensating element,
42 draw high.The prime of bias circuit 20 carries out the adjusting of voltage to adapt to different device under test and application by adjustable resistance RP
Circuit.First operational amplifier U1 passes through the first operational amplifier here as voltage follower, the rear class of bias circuit 20
U1（For voltage follower, amplification factor 1, improves carrying load ability）By partial pressure（First resistor R1, second resistance R2 and adjustable
The partial pressure of resistance RP）Voltage afterwards（Input signal）Followed, be put into the anti-phase defeated of the second operational amplifier in operational amplifier circuit
Enter end；Further voltage stabilizing and enhancing, improve stabilization of level after partial pressure.
In further embodiment, the bias circuit 20 further includes the first capacitance C1 and the second capacitance C2；First electricity
Hold one end of one end connection adjustable resistance RP of C1 and the other end connection adjustable resistance of second source end VCC2, the first capacitance C1
The other end and ground of RP, one end of the second capacitance C2 connect the positive supply foot and the first power end of the first operational amplifier U1
The other end ground connection of VCC1, the second capacitance C2.First capacitance C1 is used to filter to ensure the stability of input signal, the second capacitance
C2 is used to be filtered into the supply voltage that the first operational amplifier U1 provides stabilization.
The operational amplifier circuit 30 include the second operational amplifier U2, the 4th resistance R4, the 5th resistance R5, the 6th resistance R6,
7th resistance R7 and the 3rd capacitance C3；The in-phase input end of the second operational amplifier U2 connect the 4th resistance R4 one end and
One end of 7th resistance R7, the signal pins D of the other end connecting interface 10 of the 4th resistance R4, another termination of the 7th resistance R7
Ground, the 3rd capacitance C3 is in parallel with the 7th resistance R7, and the inverting input of the second operational amplifier U2 connects the one of the 5th resistance R5
End and one end of the 6th resistance R6, the other end of the 5th resistance R5 connect the output terminal of the first operational amplifier U1, the second computing
The output terminal of amplifier U2 connects the other end and MCU of the 6th resistance R6.
Wherein, the second operational amplifier U2 and its peripheral components composition amplifying circuit, the first operational amplifier U1 is exported
Level signal compared with the detection signal for the device under test that interface 10 transmits.When device under test is not fallen off, then is exported
The output signal SIG_GAS of two operational amplifier U2 is an interval value corresponding with the concentration value of device under test；When coming off,
Output signal SIG_GAS is the value outside a section.So MCU can just identify that device under test detects dense according to interval value
Angle value；Exceptional value is identified as according to the value outside section, judges that device under test connection is problematic.In the specific implementation, also can be
One fixed magnitude of voltage is set outside the scope of interval value, when MCU detects that this magnitude of voltage fixed can determine that device to be measured
Part has come off, and avoids the detected value of output error.
In further embodiment, the operational amplifier circuit 30 further includes the 8th resistance R8 and the 4th capacitance C4；8th electricity
The one end for hindering R8 connects the output terminal of the second operational amplifier U2, and the other end of the 8th resistance R8 connects one end of the 4th capacitance C4
And the other end ground connection of MCU, the 4th capacitance C4.The filter circuit of 8th resistance R8 and the 4th capacitance C4 compositions can make output signal
SIG_GAS more smooth steadies, so that MCU identifies more accurate concentration value.
In the present embodiment, the thermoelectricity resistance value of detecting element 41 and compensating element, 42 approaches, and preferably both are equal；Examined in sample
When surveying environmental change, it is higher or relatively low to be unlikely to magnitude of voltage, that is, plays temperature compensation function；One when varying with temperature, other one
A also to follow same change, the current potential of such output terminal is constant.The resistance value of 4th resistance R4 and the 5th resistance R5 approaches, compared with
Both good ground is equal.The resistance value of 6th resistance R6 and the 7th resistance R7 approaches, and preferably both are equal.
Please continue to refer to Fig. 2, by taking device under test is sensor as an example, the operation principle of the detection device is as follows：
It is powered before normal work, allows sensor to preheat the regular hour in cleaned air, then adjust adjustable resistance
RP changes the voltage on the in-phase input end of the first operational amplifier U1, which is followed by the first operational amplifier U1,
The inverting input of the second operational amplifier is output to, the second operational amplifier exports an output signal SIG_ for being more than zero V
GAS（Voltage is V1, such as 0.5V）.
When sensor detects object gas, the equivalent resistance of detecting element 41 can occur to change accordingly, detection
The pressure value of signal also respective change and by the 4th resistance R4 enter the second operational amplifier U2 in-phase input end, export signal
SIG_GAS also and then changes, and change normal range (NR) is generally 0.5V ~ 2V.Circuit works normally.Export the electricity of signal SIG_GAS
Pressure value can carry out converted measurement with the analog-to-digital converting unit of MCU, and MCU directly shows corresponding concentration on the screen
Value.
When sensor breaks down, point three kinds of situations：
1st, sensor comes off, and the detection signal for being input to the 4th resistance R4 at this time is vacant state, and the 7th resistance R7 is by
The output signal SIG_GAS of voltage pull-down on the in-phase input end of two operational amplifier U2, at this time the second operational amplifier U2
Voltage be much smaller than V1（0.5V）.MCU is by judging that the voltage is less than 0.5V, you can is identified as sensor and comes off.
2nd, compensating element, 42 disconnects, and detecting element 41 is normal, electric bridge（By first resistor R1, second resistance R2, detecting element
41 and compensating element, 42 form）Lose permanent.Detection signal on the in-phase input end of second operational amplifier U2 is detected element 41
With being pulled down to, the voltage on the in-phase input end of the second operational amplifier U2 is also quite zero, and principle is same as above 1, that is, exports signal
The voltage of SIG_GAS is much smaller than V1（0.5V）.MCU is by judging that the voltage is less than 0.5V, you can it is identified as sensor and comes off, can
Reminded using modes such as sound-light alarms.
3rd, compensating element, 42 is normal, and detecting element 41 disconnects, and electric bridge loses permanent.At this moment detection signal is drawn high by compensating element, 42
To the voltage of second source end VCC2, the voltage on the in-phase input end of the second operational amplifier U2 is maximum.Then output letter
The voltage of number SIG_GAS also reaches maximum.The value of the value and normal operation of sensor scope is much bigger, by detecting the point
Voltage it may determine that being sensor release failure.
It is to be appreciated that other type of alarms or numerical value display mode can also be used, it is not restricted herein.
In conclusion detection device provided by the utility model, the output detection signal pair when device under test normally connects
The concentration value answered, the three kinds of state output corresponding voltages to be come off according to device under test, MCU judge the voltage not in normal range (NR)
It can detect that device under test comes off and prompts, monitoring personnel is understood the connection status of device under test at any time, allow and monitor people
Member preferably makes corresponding measure according to fact of case, avoids causing the error in data in collection.
It is understood that for those of ordinary skills, can with technical solution according to the present utility model and
The design of its utility model is subject to equivalent substitution or change, and all these changes or replacement should all belong to appended by the utility model
Scope of the claims.
Claims (7)
1. a kind of be used to detect the detection device whether device connection status comes off, it is connected with MCU, it is characterised in that including connecing
Mouth, bias circuit and operational amplifier circuit；
The interface is used for transmission the detection signal of device under test, and the magnitude of voltage of the detection signal is according to the connection of device under test
State corresponds to change；The bias circuit is used to export corresponding biasing voltage signal according to different device under test；The fortune
Electric discharge road will detect signal compared with biasing voltage signal, and the value correspondence change of output pressure outputs signal to MCU to judge
The connection status of device under test；
The interface connection device under test and operational amplifier circuit, bias circuit connection operational amplifier circuit and device under test, operational amplifier circuit connect
Meet MCU.
2. according to claim 1 be used to detect the detection device whether device connection status comes off, it is characterised in that institute
It is sensor to state device under test, and sensor is made of detecting element and compensating element, encapsulation.
3. according to claim 2 be used to detect the detection device whether device connection status comes off, it is characterised in that institute
State supply pin connection second source end, the other end and bias circuit of compensating element, of interface；The signal pins connection amplifier of interface
One end of circuit, one end of detecting element and compensating element,；The other end of the lower margin connecting detection element of interface, bias circuit and
Ground.
4. according to claim 3 be used to detect the detection device whether device connection status comes off, it is characterised in that institute
Stating bias circuit includes the first operational amplifier, first resistor, second resistance, 3rd resistor and adjustable resistance；First fortune
Calculate one end, one end of second resistance and the control terminal of adjustable resistance of the in-phase input end connection first resistor of amplifier；First
One end and second source end of the other end connection adjustable resistance of resistance, the other end of second resistance connect the another of adjustable resistance
End and ground, one end of the inverting input connection 3rd resistor of the first operational amplifier, the output terminal of the first operational amplifier connect
The other end and operational amplifier circuit of 3rd resistor are connect, the positive supply foot of the first operational amplifier connects the first power end, the first computing
The negative supply foot ground connection of amplifier；
The other end of the first resistor is also connected with the other end of compensating element, and the other end of second resistance is also connected with detecting element
The other end.
5. according to claim 4 be used to detect the detection device whether device connection status comes off, it is characterised in that institute
State bias circuit and further include the first capacitance and the second capacitance；One end and second of one end connection adjustable resistance of first capacitance
Power end, the other end and ground of the other end connection adjustable resistance of the first capacitance, one end of the second capacitance connects the first computing and puts
The positive supply foot and the first power end of big device, the other end ground connection of the second capacitance.
6. according to claim 5 be used to detect the detection device whether device connection status comes off, it is characterised in that institute
Stating operational amplifier circuit includes the second operational amplifier, the 4th resistance, the 5th resistance, the 6th resistance, the 7th resistance and the 3rd capacitance；Institute
State the second operational amplifier in-phase input end connect the 4th resistance one end and the 7th resistance one end, the 4th resistance it is another
Hold the signal pins of connecting interface, the other end ground connection of the 7th resistance, the 3rd capacitance and the 7th resistor coupled in parallel, the second operational amplifier
Inverting input connect one end of the 5th resistance and one end of the 6th resistance, the other end of the 5th resistance connects the first computing and puts
The output terminal of big device, the output terminal of the second operational amplifier connect the other end and MCU of the 6th resistance.
7. according to claim 6 be used to detect the detection device whether device connection status comes off, it is characterised in that institute
State operational amplifier circuit and further include the 8th resistance and the 4th capacitance；One end of 8th resistance connects the output of the second operational amplifier
End, the other end of the 8th resistance connect one end and the MCU of the 4th capacitance, the other end ground connection of the 4th capacitance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721153287.7U CN207249037U (en) | 2017-09-11 | 2017-09-11 | It is a kind of to be used to detect the detection device whether device connection status comes off |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721153287.7U CN207249037U (en) | 2017-09-11 | 2017-09-11 | It is a kind of to be used to detect the detection device whether device connection status comes off |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN207249037U true CN207249037U (en) | 2018-04-17 |
Family
ID=61887703
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201721153287.7U Active CN207249037U (en) | 2017-09-11 | 2017-09-11 | It is a kind of to be used to detect the detection device whether device connection status comes off |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN207249037U (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108896873A (en) * | 2018-07-09 | 2018-11-27 | 武汉瑞莱保能源技术有限公司 | A kind of remote monitoring of power transmission line and fault location system |
| CN109194331A (en) * | 2018-08-29 | 2019-01-11 | 苏州瑞迈斯医疗科技有限公司 | Electronic device and the method for correcting comparator in the electronic device |
| CN109358259A (en) * | 2018-10-08 | 2019-02-19 | 大族激光科技产业集团股份有限公司 | A kind of system and method judging capacitance sensor working condition |
| CN109765479A (en) * | 2019-01-28 | 2019-05-17 | 合肥京东方视讯科技有限公司 | A kind of circuit board Short Item detection device and method |
| CN110243915A (en) * | 2019-06-20 | 2019-09-17 | 成都市融汇智信息技术有限公司 | Electrochemical sensor automatic identification and ineffectiveness detection system and its detection method |
| CN111751505A (en) * | 2020-07-17 | 2020-10-09 | 深圳市诺安环境安全股份有限公司 | Digital gas probe circuit, digital gas probe and system |
-
2017
- 2017-09-11 CN CN201721153287.7U patent/CN207249037U/en active Active
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108896873A (en) * | 2018-07-09 | 2018-11-27 | 武汉瑞莱保能源技术有限公司 | A kind of remote monitoring of power transmission line and fault location system |
| CN109194331A (en) * | 2018-08-29 | 2019-01-11 | 苏州瑞迈斯医疗科技有限公司 | Electronic device and the method for correcting comparator in the electronic device |
| CN109358259A (en) * | 2018-10-08 | 2019-02-19 | 大族激光科技产业集团股份有限公司 | A kind of system and method judging capacitance sensor working condition |
| CN109765479A (en) * | 2019-01-28 | 2019-05-17 | 合肥京东方视讯科技有限公司 | A kind of circuit board Short Item detection device and method |
| CN109765479B (en) * | 2019-01-28 | 2021-10-01 | 合肥京东方视讯科技有限公司 | Device and method for detecting missing parts of circuit board |
| US11219134B2 (en) | 2019-01-28 | 2022-01-04 | Hefei Boe Vision-Electronic Technology Co., Ltd. | Device and method for detecting missing element on circuit board |
| CN110243915A (en) * | 2019-06-20 | 2019-09-17 | 成都市融汇智信息技术有限公司 | Electrochemical sensor automatic identification and ineffectiveness detection system and its detection method |
| CN110243915B (en) * | 2019-06-20 | 2021-12-17 | 成都市融汇智信息技术有限公司 | Electrochemical sensor automatic identification and failure detection system and detection method thereof |
| CN111751505A (en) * | 2020-07-17 | 2020-10-09 | 深圳市诺安环境安全股份有限公司 | Digital gas probe circuit, digital gas probe and system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN207249037U (en) | It is a kind of to be used to detect the detection device whether device connection status comes off | |
| CN203414570U (en) | Testing circuit for zero-drift operation amplifier | |
| CN106679841A (en) | Temperature detecting device and temperature detecting method | |
| CN203759112U (en) | High-frequency current detection circuit | |
| CN108169568A (en) | Milliohm resistance measuring circuit | |
| CN106248240B (en) | A kind of temperature transmitter with temperature-compensating | |
| CN203117295U (en) | Resistance value detection circuit and device | |
| CN204903740U (en) | Power detecting circuit | |
| CN207281217U (en) | A kind of amplifier circuit of compatibility electric current and temperature detection | |
| CN209590068U (en) | Constant current source power supply system | |
| CN207424104U (en) | Vibration amplifier sensor capacitance amount detecting device | |
| CN102759366B (en) | Detection device of optical fiber gyroscope optical module | |
| CN210221888U (en) | Moisture meter system convenient to data acquisition | |
| CN207976195U (en) | A kind of liquid level real-time detection apparatus | |
| US8143881B2 (en) | Current measuring apparatus for power supply | |
| CN206057428U (en) | A kind of digital galvanometer for microwave waveguide measuring system | |
| CN104166035A (en) | Negative voltage detection apparatus | |
| CN208187333U (en) | A kind of capacitive displacement sensing device transmitted at a distance based on transformer secondary output | |
| CN207992320U (en) | Milliohm resistance measuring circuit | |
| CN202533212U (en) | Electronic oil pressure sensor with dynamic equivalent mode | |
| CN105547951B (en) | Measuring concentration of granules in certain system in low concentration particulate matter In-circiut tester | |
| CN206161234U (en) | Balanced detection device of accelerometer | |
| CN204903669U (en) | Tester | |
| CN206038183U (en) | Temperature becomes send device with temperature compensating | |
| CN204535739U (en) | A kind of data collector |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |