CN202841092U - High-side switch output circuit with short-circuit protection function - Google Patents
High-side switch output circuit with short-circuit protection function Download PDFInfo
- Publication number
- CN202841092U CN202841092U CN 201220387507 CN201220387507U CN202841092U CN 202841092 U CN202841092 U CN 202841092U CN 201220387507 CN201220387507 CN 201220387507 CN 201220387507 U CN201220387507 U CN 201220387507U CN 202841092 U CN202841092 U CN 202841092U
- Authority
- CN
- China
- Prior art keywords
- circuit
- switching tube
- links
- switch pipe
- resistance
- 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.)
- Expired - Fee Related
Links
- 238000005070 sampling Methods 0.000 claims abstract description 6
- 230000001681 protective effect Effects 0.000 claims description 13
- 238000001514 detection method Methods 0.000 abstract description 2
- 238000004378 air conditioning Methods 0.000 description 2
- 230000007812 deficiency Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000012353 t test Methods 0.000 description 1
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The utility model relates to a high-side switch output circuit with the short-circuit protection function, which is characterized by comprising a first switching tube, a second switching tube, a sampling circuit used for acquiring the signal of a current flowing through the second switching tube and then converting the current signal into a voltage signal, and a protection circuit used for switching off the second switching tube when the voltage signal is greater than or equal to a preset value. The high-side switch output circuit with the short-circuit protection function can be adopted as the circuits of the electrical equipment of a vehicle to output a high level so as to drive the operation of an electronic control unit (ECU), a partial pressure detection unit, a small-current relay and the like of the vehicle. The high-side switch output circuit has the over-current short-circuit protection function and is simple in circuit structure. Since the circuit only comprises switching tubes, resistors and a sampling circuit, the circuit is very low in cost. In addition, the parameters of the circuit can be adjusted according to needs, so that the circuit is more flexible in driving mode than a special chip.
Description
Technical field
The utility model relates generally to the flash switching circuit, relates in particular to a kind of flash switch output circuit with short-circuit protection.
Technical background
Usually needing output low level or high level to send the signals such as compressor request in the air-conditioner controller, is in the situation of microprocessor detection in interface end, all is to adopt special-purpose lower edge switch or flash switch to go to drive.Special driving chip is generally comparatively expensive, also has at present the NPN of employing triode to cooperate the PNP triode to replace the flash switch, but can't test by short-circuit stability.When the circuit shorted to earth, because without the current limliting measure, immediate current is excessive, triode burns out immediately, can not recover, and fuction output is unusual.
Summary of the invention
The purpose of this utility model is to overcome above-mentioned the deficiencies in the prior art and shortcoming, and a kind of flash switch output circuit with short-circuit protection is provided.
The purpose of this utility model realizes by following technical proposals: a kind of flash switch output circuit with short-circuit protection comprises that the first switching tube, second switch pipe, acquisition stream cross the current signal of second switch pipe and this current signal is converted to the sample circuit of voltage signal and the protective circuit of turn-offing described second switch pipe during more than or equal to preset value at described voltage signal.Wherein, the control end of described the first switching tube links to each other with the control signal input, and its first end links to each other by the control end of resistance with the second switch pipe, its second end ground connection.The first end of described second switch pipe links to each other with the control signal output, and to control signal output output high level or high resistant signal, its second end links to each other with constant pressure source by sample circuit.Described protective circuit comprises the 3rd switching tube, the first resistance and the second resistance; The control end of described the 3rd switching tube links to each other with the tie point of the first and second resistance, and its first end links to each other with the control end of second switch pipe, and its second end links to each other with described constant pressure source; The series arm that described the first and second resistance form is in parallel with sample circuit.
Preferably, described the first switching tube is NPN type triode, and described second switch pipe is the positive-negative-positive triode; Wherein the base stage of triode is its control end, and its current collection is its first end very, and its emission is its second end very.
Preferably, described sample circuit comprises sampling resistor, and an end of sampling resistor links to each other with the second end of second switch pipe, and the other end links to each other with described constant pressure source.
Preferably, described the 3rd switching tube is the positive-negative-positive triode, and its base stage is its control end, and its current collection is its first end very, and its emission is its second end very.
The utility model has the overcurrent short-circuit protection function with the flash switch output circuit of short-circuit protection, and circuit structure is simple, only comprises switching tube, resistance and sample circuit, and cost is very cheap.In addition, circuit parameter can be adjusted as required, and is more flexible than adopting special chip to drive.This circuit is applicable to export high level and drives the appliance circuits such as vehicle electronic control unit (ECU) dividing potential drop detecting unit and little current relay.
Description of drawings
Fig. 1 is the circuit structure schematic diagram with the flash switch output circuit of short-circuit protection of the utility model one embodiment.
Embodiment
Below in conjunction with embodiment and accompanying drawing the utility model is described in further detail, but execution mode of the present utility model is not limited to this.
As shown in Figure 1, in the preferred embodiment, mainly comprise the first switching tube, second switch pipe, sample circuit and protective circuit with the flash switch output circuit of short-circuit protection.In the present embodiment, this flash switch output circuit is applied to automotive air-conditioning controller, is used for exporting corresponding high level or high resistant signal according to the control signal of air-conditioner controller to automobile microcontroller (MCU) or vehicle electronic control unit (ECU).Therefore, the control signal input of this flash switch output circuit links to each other with a signal output part CTRL of air-conditioner controller, and its control signal output output links to each other with the signal input part of MCU or ECU.
Wherein, the control end of the first switching tube links to each other with control signal output CTRL, and its first end links to each other its second end ground connection by the 3rd resistance R 3 with the control end of second switch pipe.The first end of second switch pipe links to each other with control signal output output, is used for to control signal output output output high level or high resistant signal, and its second end links to each other with constant pressure source VBAT by sample circuit.In the present embodiment, the first switching tube is NPN type triode, and the second switch pipe is the positive-negative-positive triode, and the base stage of triode is its control end, and the current collection of triode is its first end very, and the emission of triode is its second end very.
Sample circuit is used for acquisition stream and crosses the current signal of second switch pipe and this current signal is converted to voltage signal.In the present embodiment, sample circuit is used for the electric current that acquisition stream is crossed second switch pipe collector and emitter, and it comprises that a resistance is much smaller than the 4th resistance of 1K Ω, for example resistance of 10 Ω.The 4th resistance one end links to each other with the emitter of second switch pipe, another termination constant pressure source VABT, thus detect in real time the electric current that flows through the second switch pipe, and output voltage signal.
Turn-off the second switch pipe when protective circuit is used for voltage signal in sample circuit output more than or equal to preset value, thereby the electric current that effectively prevents from flowing through the second switch pipe is too large, causes the second switch pipe to break down.In the present embodiment, protective circuit comprises the 3rd switching tube, the first resistance R 1 and the second resistance R 2.The control end of the 3rd switching tube links to each other with the tie point of the first resistance R 1 and the second resistance R 2, and its first end links to each other with the control end of second switch pipe, and its second end links to each other with constant pressure source VBAT.In the present embodiment, the 3rd switching tube is the positive-negative-positive triode, and its base stage is its control end, and its current collection is its first end very, and its emission is its second end very.The series arm that the first and second resistance form is in parallel with sample circuit.
In the work, automotive air-conditioning controller is judged when needing the output high level signal, it exports a high level by signal output part CTRL to the control signal input of flash switch output circuit, make the first switching tube normally, thereby also conducting of second switch pipe, output exports a high level to the control signal output, and this high level voltage and constant pressure source VBAT output are basic identical.Circuit normal operation this moment, protective circuit is inoperative.
When control signal output output shorted to earth, the electric current that flows through the second switch pipe will increase fast, the then corresponding increase of the voltage at sample circuit two ends (also being the voltage at the series arm two ends of the first and second resistance R 1, R2 composition), corresponding, the corresponding increase with the second terminal voltage of the control end of the 3rd switching tube.When the voltage at sample circuit two ends reached preset value, protective circuit can start, the 3rd switching tube conducting; second switch management and control terminal voltage processed is drawn high (meeting constant pressure source VBAT); thereby second switch pipe cut-off with the power consumption control of second switch pipe within the limits prescribed, is avoided the damage of element.After the cut-off of second switch pipe, the voltage at sample circuit two ends becomes 0V, and then protective circuit quits work, the cut-off of the 3rd switching tube, and the first and second switching tubes are subjected to the control of signal output part CTRL again.After short circuit was cancelled, the sample circuit output end voltage was lower than predetermined threshold value, and then protective circuit quits work, the cut-off of the 3rd switching tube, and the first and second switching tubes are subjected to the control of signal output part CTRL again.
It will be appreciated by those skilled in the art that the resistors match value of protective circuit can change, when changing resistance value, the threshold value that protective circuit is opened also can change thereupon, and so just the electric current of control circuit neatly reaches the maximization of output current value.
Sample circuit adopts very little impedance, can not have influence on the output impedance of circuit, in the constant situation of other circuit parameters, can not have influence on power output.
To sum up, the utility model has the overcurrent short-circuit protection function with the flash switch output circuit of short-circuit protection, and circuit structure is simple, only comprises switching tube, resistance and sample circuit, and cost is very cheap.In addition, circuit parameter can be adjusted as required, and is more flexible than adopting special chip to drive, and is applicable to export high level and drives the appliance circuits such as vehicle electronic control unit (ECU) dividing potential drop detecting unit and little current relay.
Above-described embodiment is the better execution mode of the utility model; but execution mode of the present utility model is not restricted to the described embodiments; other any do not deviate from change, modification, replacement, combination, the simplification of doing under Spirit Essence of the present utility model and the principle; be the substitute mode of equivalence, be included within the protection range of the present utility model.
Claims (4)
1. the flash switch output circuit with short-circuit protection is characterized in that, comprising:
The first switching tube, second switch pipe, acquisition stream are crossed the current signal of second switch pipe and this current signal are converted to the sample circuit of voltage signal and the protective circuit of turn-offing described second switch pipe during more than or equal to preset value at described voltage signal;
Wherein, the control end of described the first switching tube links to each other with the control signal input, and its first end links to each other by the control end of resistance with the second switch pipe, its second end ground connection; The first end of described second switch pipe links to each other with the control signal output, and to control signal output output high level or high resistant signal, its second end links to each other with constant pressure source by sample circuit;
Described protective circuit comprises the 3rd switching tube, the first resistance and the second resistance; The control end of described the 3rd switching tube links to each other with the tie point of the first and second resistance, and its first end links to each other with the control end of second switch pipe, and its second end links to each other with described constant pressure source; The series arm that described the first and second resistance form is in parallel with sample circuit.
2. described flash switch output circuit according to claim 1 is characterized in that described the first switching tube is NPN type triode, and described second switch pipe is the positive-negative-positive triode; Wherein the base stage of triode is its control end, and its current collection is its first end very, and its emission is its second end very.
3. flash switch output circuit according to claim 2, it is characterized in that: described sample circuit comprises sampling resistor, and an end of sampling resistor links to each other with the second end of second switch pipe, and the other end links to each other with described constant pressure source.
4. flash switch output circuit according to claim 1, it is characterized in that: described the 3rd switching tube is the positive-negative-positive triode, and its base stage is its control end, and its current collection is its first end very, and its emission is its second end very.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220387507 CN202841092U (en) | 2012-08-07 | 2012-08-07 | High-side switch output circuit with short-circuit protection function |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220387507 CN202841092U (en) | 2012-08-07 | 2012-08-07 | High-side switch output circuit with short-circuit protection function |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202841092U true CN202841092U (en) | 2013-03-27 |
Family
ID=47952686
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201220387507 Expired - Fee Related CN202841092U (en) | 2012-08-07 | 2012-08-07 | High-side switch output circuit with short-circuit protection function |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN202841092U (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104168011A (en) * | 2014-05-06 | 2014-11-26 | 浙江中控自动化仪表有限公司 | Simulation signal input circuit |
| CN109032045A (en) * | 2018-09-28 | 2018-12-18 | 科博达技术股份有限公司 | Vehicle-mounted high side switches |
| CN110601512A (en) * | 2019-09-24 | 2019-12-20 | 广西新发展交通集团有限公司 | Discrete high-side driving circuit system |
| CN112310937A (en) * | 2020-10-16 | 2021-02-02 | 浪潮电子信息产业股份有限公司 | Slow start protection circuit and circuit protection integrated chip |
| CN114167164A (en) * | 2021-11-11 | 2022-03-11 | 潍柴动力股份有限公司 | High-side power supply detection method and device, electronic equipment and storage medium |
-
2012
- 2012-08-07 CN CN 201220387507 patent/CN202841092U/en not_active Expired - Fee Related
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104168011A (en) * | 2014-05-06 | 2014-11-26 | 浙江中控自动化仪表有限公司 | Simulation signal input circuit |
| CN104168011B (en) * | 2014-05-06 | 2017-07-28 | 浙江中控自动化仪表有限公司 | A kind of analog signal input circuit |
| CN109032045A (en) * | 2018-09-28 | 2018-12-18 | 科博达技术股份有限公司 | Vehicle-mounted high side switches |
| CN109032045B (en) * | 2018-09-28 | 2024-03-26 | 科博达技术股份有限公司 | Vehicle-mounted high-side switch |
| CN110601512A (en) * | 2019-09-24 | 2019-12-20 | 广西新发展交通集团有限公司 | Discrete high-side driving circuit system |
| CN112310937A (en) * | 2020-10-16 | 2021-02-02 | 浪潮电子信息产业股份有限公司 | Slow start protection circuit and circuit protection integrated chip |
| US12237670B2 (en) | 2020-10-16 | 2025-02-25 | Inspur Electronic Information Industry Co., Ltd. | Soft-start protection circuit and circuit protection integrated chip |
| CN114167164A (en) * | 2021-11-11 | 2022-03-11 | 潍柴动力股份有限公司 | High-side power supply detection method and device, electronic equipment and storage medium |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN202798648U (en) | Low-side switch output circuit with short-circuit protection | |
| CN202841092U (en) | High-side switch output circuit with short-circuit protection function | |
| CN101720147B (en) | LED driving circuit and LED device | |
| CN203850812U (en) | Load short circuit protection circuit | |
| CN206225983U (en) | Over-voltage over-current protection circuit | |
| CN204205549U (en) | Overvoltage protection | |
| CN202049191U (en) | Overvoltage undervoltage detection circuit | |
| CN102890184A (en) | Zero-crossing detection circuit based on optocoupler | |
| CN203814006U (en) | LED working state detection circuit | |
| CN104062538A (en) | Method for monitoring short circuit and circuit break of vehicle-mounted relay or contactor coil | |
| CN201698967U (en) | Driving circuit of improved magnetic latching relay of electric energy meter | |
| CN205229425U (en) | A cross under -voltage failure detector circuit for on -vehicle low pressure battery of electric automobile | |
| CN202261136U (en) | Motor and overcurrent detection circuit thereof | |
| CN209448421U (en) | A kind of overvoltage/undervoltage protection detection circuit of low cost high stability | |
| CN204028275U (en) | A kind of radio reception automatic antenna power supply state testing circuit | |
| CN202351726U (en) | Resistance and capacitance step-down control circuit | |
| CN206685314U (en) | A kind of relay with load faulty detection function | |
| CN204008929U (en) | A kind of solenoid trouble-shooter | |
| CN209041081U (en) | A kind of protection circuit of air compressor machine long-distance monitorng device | |
| CN103412505A (en) | Circuit for controlling and monitoring remote switches | |
| CN204334538U (en) | A small current high-end drive circuit | |
| CN203025235U (en) | Voltage state detection circuit of output channel | |
| CN104577961B (en) | Over-pressed power-off protecting circuit | |
| CN201623477U (en) | Overvoltage protection device of current transformer | |
| CN201341255Y (en) | LED lamp current switch and control circuit for vehicle body control module |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20130327 Termination date: 20140807 |
|
| EXPY | Termination of patent right or utility model |