CN206498183U - A kind of over-and under-voltage protection circuit - Google Patents

A kind of over-and under-voltage protection circuit Download PDF

Info

Publication number
CN206498183U
CN206498183U CN201720156248.6U CN201720156248U CN206498183U CN 206498183 U CN206498183 U CN 206498183U CN 201720156248 U CN201720156248 U CN 201720156248U CN 206498183 U CN206498183 U CN 206498183U
Authority
CN
China
Prior art keywords
voltage
npn triode
regulator diode
under
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.)
Active
Application number
CN201720156248.6U
Other languages
Chinese (zh)
Inventor
罗海轮
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Guangzhou Hongyi Electronics Co Ltd
Original Assignee
Guangzhou Hongyi Electronics Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Guangzhou Hongyi Electronics Co Ltd filed Critical Guangzhou Hongyi Electronics Co Ltd
Priority to CN201720156248.6U priority Critical patent/CN206498183U/en
Application granted granted Critical
Publication of CN206498183U publication Critical patent/CN206498183U/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Abstract

The utility model is related to a kind of over-and under-voltage protection circuit, including voltage input end, the voltage input end passes through overvoltage crowbar, under-voltage protecting circuit and control circuit connection voltage output end, the first voltage-regulator diode is provided with the overvoltage crowbar, the second voltage-regulator diode is provided with the under-voltage protecting circuit, the breakdown voltage of first voltage-regulator diode is more than the second voltage-regulator diode, when the voltage of voltage input end is between the first voltage-regulator diode and the second voltage-regulator diode breakdown voltage, voltage output end just has voltage output, the utility model controls whether overvoltage crowbar is opened with under-voltage protecting circuit by the first voltage-regulator diode and the second voltage-regulator diode, further control controls the triode in circuit, triode is equivalent to switch, so as to which whether control voltage output end has voltage output, the utility model provides a kind of simple, easily over-and under-voltage protection circuit.

Description

A kind of over-and under-voltage protection circuit
Technical field
The utility model is related to a kind of power circuit, and in particular to a kind of over-and under-voltage protection circuit.
Background technology
During electrical equipment use, voltage is excessive or voltage is too small can all cause damage of product, and general power supply manufacturers exist Produce during power supply, over-and under-voltage protection circuit can be designed in a power, so that the use of electrical appliance is protected, more life Business men can select to be collected the electric signal of voltage output end using comparison circuit, then feed back in single-chip microcomputer, pass through list Piece machine is controlled to the voltage of voltage output end, this control mode has that circuit is complicated, is unfavorable for production and processing, cost compared with High the shortcomings of.
Utility model content
The utility model passes through the first voltage-regulator diode and second its object is to disclose a kind of over-and under-voltage protection circuit Whether voltage-regulator diode control overvoltage crowbar is opened with under-voltage protecting circuit, further three poles in control control circuit Pipe, triode is equivalent to switch, so that whether control voltage output end has voltage output, the utility model provides a kind of letter List, easily over-and under-voltage protection circuit.
Realizing the technical scheme of over-and under-voltage protection circuit described in the utility model is:A kind of over-and under-voltage protection circuit, Including voltage input end, the voltage input end is by overvoltage crowbar, under-voltage protecting circuit and control circuit connection voltage Output end, the overvoltage crowbar includes the first voltage-regulator diode, and the positive pole of the voltage input end connects the first voltage stabilizing two The negative pole of pole pipe, the negative pole ground connection of the voltage input end, positive pole connection first resistor one end of first voltage-regulator diode, The first resistor other end is grounded by second resistance, and the first resistor other end also connects first by 3rd resistor The base stage of NPN triode, the under-voltage protecting circuit includes the second voltage-regulator diode, the positive pole connection the of the voltage input end The negative pole of two voltage-regulator diodes, the positive pole of the cathode connecting diode of second voltage-regulator diode, the negative pole of the diode The colelctor electrode of the first NPN triode and the base stage of the second NPN triode are connected by the 4th resistance, the control circuit includes the One NPN triode, the second NPN triode and PNP triode, the grounded emitter of first NPN triode, described first The colelctor electrode of NPN triode connects the base stage of the second NPN triode, and the colelctor electrode of second NPN triode passes through the 5th electricity Resistance and the 6th resistance connect the positive pole of voltage output end, the collector emitter ground connection of second NPN triode, the described 5th The base stage of PNP triode is connected between resistance and the 6th resistance provided with branch, the colelctor electrode connection voltage of the PNP triode is defeated Go out the positive pole at end, the emitter stage of the PNP triode connects the negative pole of voltage output end, and the negative pole of the voltage output end passes through First capacity earth.
Further, the breakdown voltage of first voltage-regulator diode is more than the breakdown voltage of the second voltage-regulator diode.
Further, branch road is provided between the negative pole of the positive pole of the voltage input end and the first voltage-regulator diode, it is described Branch road passes through the 7th resistance eutral grounding.
Further, branch road, the branch road are provided between the positive pole of first voltage-regulator diode and the positive pole of diode Pass through the 8th resistance eutral grounding.
Further, branch road is provided between the colelctor electrode of first NPN triode and the base stage of the second NPN triode, The branch road passes through the 9th resistance eutral grounding.
Further, the base stage of first NPN triode passes through the second capacity earth.
Brief description of the drawings
Fig. 1 is the circuit diagram of over-and under-voltage protection circuit described in the utility model.
Embodiment
Below in conjunction with the accompanying drawing in the utility model embodiment, the technical scheme in the utility model embodiment is carried out Clearly and completely describe, it is clear that described embodiment is only a part of embodiment of the utility model, rather than whole Embodiment.Based on the embodiment in the utility model, those of ordinary skill in the art are not under the premise of creative work is made The every other embodiment obtained, belongs to the scope of the utility model protection.
Embodiment:A kind of over-and under-voltage protection circuit, including voltage input end, the voltage input end pass through overvoltage protection Circuit, under-voltage protecting circuit and control circuit connection voltage output end, the overvoltage crowbar include the first voltage-regulator diode D1, the positive pole of the voltage input end connects the first voltage-regulator diode D1 negative pole, the negative pole ground connection of the voltage input end, institute The first voltage-regulator diode D1 positive pole connection first resistor R1 one end is stated, the first resistor R1 other ends pass through second resistance R2 Ground connection, the first resistor R1 other ends are also by the base stage of 3rd resistor R3 the first NPN triode Q1s of connection, the under-voltage guarantor Protection circuit includes the second voltage-regulator diode D2, and the positive pole of the voltage input end connects the second voltage-regulator diode D2 negative pole, institute The second voltage-regulator diode D2 cathode connecting diode D3 positive pole is stated, the negative pole of the diode D3 is connected by the 4th resistance R4 The colelctor electrode of the first NPN triode Q1 and the second NPN triode Q2 base stage are connect, the control circuit includes the poles of the first NPN tri- Pipe Q1, the second NPN triode Q2 and PNP triode Q3, the grounded emitter of first NPN triode Q1, the first NPN Triode Q1 colelctor electrode connects the second NPN triode Q2 base stage, and the colelctor electrode of the second NPN triode Q2 passes through the 5th Resistance R5 and the 6th resistance R6 connection voltage output ends positive pole, the collector emitter ground connection of the second NPN triode Q2, PNP triode Q3 base stage is connected between the 5th resistance R5 and the 6th resistance R6 provided with branch, the PNP triode Q3's Colelctor electrode connects the positive pole of voltage output end, and the emitter stage of the PNP triode Q3 connects the negative pole of voltage output end, the electricity The negative pole of pressure output end is grounded by the first electric capacity C1.
The breakdown voltage of the first voltage-regulator diode D1 is more than the second voltage-regulator diode D2 breakdown voltage.
Branch road is provided between the positive pole of the voltage input end and the first voltage-regulator diode D1 negative pole, the branch road passes through 7th resistance R7 is grounded, and branch road, the branch are provided between the positive pole of the first voltage-regulator diode D2 and diode D3 positive pole Road is grounded by the 8th resistance R7, is set between the colelctor electrode of first NPN triode Q1 and the second NPN triode Q2 base stage There is branch road, the branch road is grounded by the 9th resistance R9, the base stage of first NPN triode Q1 is connect by the second electric capacity C2 Ground, the 7th resistance R7, the 8th resistance R8, the 9th resistance R9 and the second electric capacity C2 effects are protection circuit, it is to avoid circuit Middle electric current is excessive or voltage is excessive.
The operation principle of the present embodiment:Following three kinds of situations can be produced in the circuit course of work:1)When voltage is less than first When voltage-regulator diode D1 and the second voltage-regulator diode D2 breakdown voltage, under-voltage protecting circuit, overvoltage crowbar are in open circuit State, so as to cause the second NPN triode Q2 base stage to be in low level state, the second NPN triode Q2 disconnects, so as to cause PNP triode Q3 disconnects, so as to cause voltage output end not have voltage output.2)When voltage higher than the first voltage-regulator diode D1 with During the second voltage-regulator diode D2 breakdown voltage, under-voltage protecting circuit, overvoltage crowbar are in channel status, the first NPN tri- Pole pipe Q1 base stage is in high level state, the conducting of the first NPN triode Q1, the second NPN triode Q2 base earth, second NPN triode Q2 disconnects, so as to cause PNP triode Q3 to disconnect, so as to cause voltage output end not have voltage output.3)Work as electricity Force down when the first voltage-regulator diode D1 is but higher than the second voltage-regulator diode D2, under-voltage protecting circuit is in channel status, overvoltage Protection circuit is in off state, and the base stage of the first NPN triode Q1 is in low level state, and the first NPN triode Q1 disconnects, Second NPN triode Q2 base stage is in high level state, the second NPN triode Q2 conductings, so as to cause PNP triode Q3 to lead It is logical, so as to cause voltage output end to have voltage output.
The beneficial effects of the utility model are:The utility model passes through the first voltage-regulator diode and the second voltage-regulator diode The break-make of effect control overvoltage crowbar and under-voltage protecting circuit, so that when realizing over-pressed or under-voltage, circuit disconnects, so that Electrical appliance is protected, this circuit design is simple, it is convenient to process and power supply production cost be reduced.

Claims (6)

1. a kind of over-and under-voltage protection circuit, including voltage input end, it is characterised in that the voltage input end is protected by overvoltage Protection circuit, under-voltage protecting circuit and control circuit connection voltage output end, the overvoltage crowbar include the pole of the first voltage stabilizing two Pipe, the positive pole of the voltage input end connects the negative pole of the first voltage-regulator diode, and the negative pole ground connection of the voltage input end is described Positive pole connection first resistor one end of first voltage-regulator diode, the first resistor other end is grounded by second resistance, described The first resistor other end also connects the base stage of the first NPN triode by 3rd resistor, and the under-voltage protecting circuit includes second Voltage-regulator diode, the positive pole of the voltage input end connects the negative pole of the second voltage-regulator diode, second voltage-regulator diode The positive pole of cathode connecting diode, the negative pole of the diode by the 4th resistance connect the first NPN triode colelctor electrode and The base stage of second NPN triode, the control circuit includes the first NPN triode, the second NPN triode and PNP triode, institute The grounded emitter of the first NPN triode is stated, the colelctor electrode of first NPN triode connects the base stage of the second NPN triode, The colelctor electrode of second NPN triode connects the positive pole of voltage output end, described second by the 5th resistance and the 6th resistance The collector emitter ground connection of NPN triode, PNP triode is connected between the 5th resistance and the 6th resistance provided with branch Base stage, the colelctor electrode of the PNP triode connects the positive pole of voltage output end, the emitter stage connection voltage of the PNP triode The negative pole of output end, the negative pole of the voltage output end passes through the first capacity earth.
2. over-and under-voltage protection circuit according to claim 1, it is characterised in that the breakdown potential of first voltage-regulator diode Breakdown voltage of the pressure more than the second voltage-regulator diode.
3. over-and under-voltage protection circuit according to claim 1, it is characterised in that the positive pole of the voltage input end and first Branch road is provided between the negative pole of voltage-regulator diode, the branch road passes through the 7th resistance eutral grounding.
4. over-and under-voltage protection circuit according to claim 1, it is characterised in that the positive pole of first voltage-regulator diode with Branch road is provided between the positive pole of diode, the branch road passes through the 8th resistance eutral grounding.
5. over-and under-voltage protection circuit according to claim 1, it is characterised in that the colelctor electrode of first NPN triode Branch road is provided between the base stage of the second NPN triode, the branch road passes through the 9th resistance eutral grounding.
6. over-and under-voltage protection circuit according to claim 1, it is characterised in that the base stage of first NPN triode is led to Cross the second capacity earth.
CN201720156248.6U 2017-02-21 2017-02-21 A kind of over-and under-voltage protection circuit Active CN206498183U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201720156248.6U CN206498183U (en) 2017-02-21 2017-02-21 A kind of over-and under-voltage protection circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201720156248.6U CN206498183U (en) 2017-02-21 2017-02-21 A kind of over-and under-voltage protection circuit

Publications (1)

Publication Number Publication Date
CN206498183U true CN206498183U (en) 2017-09-15

Family

ID=59805493

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201720156248.6U Active CN206498183U (en) 2017-02-21 2017-02-21 A kind of over-and under-voltage protection circuit

Country Status (1)

Country Link
CN (1) CN206498183U (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019080198A1 (en) * 2017-10-24 2019-05-02 佛山市顺德区美的电热电器制造有限公司 Electromagnetic induction type wireless power supply system and load sudden-change protection circuit therefor

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019080198A1 (en) * 2017-10-24 2019-05-02 佛山市顺德区美的电热电器制造有限公司 Electromagnetic induction type wireless power supply system and load sudden-change protection circuit therefor
US11101645B2 (en) 2017-10-24 2021-08-24 Foshan Shunde Midea Electrical Heating Appliances Manufacturing Co., Ltd. Electromagnetic induction type wireless power supply system and load sudden-change protection circuit thereof

Similar Documents

Publication Publication Date Title
CN103855678B (en) Overvoltage and undervoltage protection circuit of drive power source
CN103024973B (en) LED (Light-Emitting Diode) lamp and overcurrent protection circuit thereof
CN103812147B (en) Battery charging controller
CN204258271U (en) A kind of under-voltage protective switch of the short circuit supply unit
CN104298331A (en) Power supply circuit for power supply control chip
CN206498183U (en) A kind of over-and under-voltage protection circuit
CN205039517U (en) Overvoltage protection circuit
CN202503261U (en) Protective device of input voltage fluctuation
CN207541476U (en) One kind carries the external circuit breaker control circuit of combined floodgate detection function electric energy meter
CN206332432U (en) Dc bus under-voltage protecting circuit of the low cost with isolation self-locking
CN208862634U (en) A kind of power supply switching power supply circuit
CN209150713U (en) A kind of signal output apparatus and device
CN207530535U (en) A kind of voltage control circuit for automatic transfer switch controller
CN202513560U (en) Television, television power supply and television metal oxide semiconductor (MOS) tube short-circuit protection circuit
CN207638320U (en) A kind of protection circuit of variable frequency microwave power supply
CN204559106U (en) A kind of convertible frequency air-conditioner and electrolytic capacitor overvoltage crowbar thereof
CN205016987U (en) BMS activates circuit
CN202421457U (en) Motor over-current detection circuit
CN204928112U (en) Direct current surge suppression circuit and DC power supply power supply system
CN206061217U (en) The intelligent protection circuit of buffering transient high-current
CN106211479B (en) A kind of intelligent protection circuit for buffering transient high-current
CN201868933U (en) Control circuit for primary-side feedback constant-voltage current-limiting RCC charger
CN204517360U (en) Excess voltage protection
CN204425184U (en) A kind of two-supply circuit
CN204859016U (en) AC -DC converting circuit

Legal Events

Date Code Title Description
GR01 Patent grant
GR01 Patent grant