CN206364505U

CN206364505U - A kind of power supply short-circuit protection circuit

Info

Publication number: CN206364505U
Application number: CN201720053932.1U
Authority: CN
Inventors: 胡雪松
Original assignee: BEIJING WEIGUAN ELECTRIC Co Ltd
Current assignee: BEIJING WEIGUAN ELECTRIC Co Ltd
Priority date: 2017-01-10
Filing date: 2017-01-10
Publication date: 2017-07-28
Anticipated expiration: 2027-01-10

Abstract

The utility model discloses a kind of power supply short-circuit protection circuit for belonging to power-supply device technical field; including power source protective module; the power source protective module includes overcurrent protection module and short circuit protection module, and the two ends of overcurrent protection module and short circuit protection module are all connected with power supply output module, power supply feedback module respectively.Protection circuit is directly embedded into original current supply circuit module by the utility model, and defencive function is realized by original energy supply control module, it is to avoid cause device damage when electrical equipment and short-circuit power source internal.

Description

A kind of power supply short-circuit protection circuit

Technical field

The utility model belongs to power-supply device technical field, and in particular to a kind of power supply short-circuit protection circuit.

Background technology

Power supply uses an essential part as electrical equipment, is always one of the important guarantee that electrical equipment runs well.Open The features such as powered-down source has small volume, lightweight, conversion efficiency is high, is widely used in Industry Control, communication office, family disappears Take etc. in various electronic equipments.It is especially various to protect but power supply has different technical specifications and index with the difference of electronic equipment Protective function, short-circuit protection more receives much attention as most important of which function.For short-circuit protection, it is common practice to Output end detects voltage or electric current, when output voltage is too high, too low or during too high electric current, makes circuit be stopped to reach short circuit The purpose of protection；This occurs all the way for the Switching Power Supply of multiple-channel output direct current voltage simultaneously as long as output end has Problem will influence the normal work of whole Switching Power Supply.

System is in the case of output end loop short circuit, and power switch will be turned off rapidly, prevent excessive electric current is burnt out from setting It is standby.When Switching Power Supply has multiple-channel output branch road, it is desirable to which the output of shut-off does not interfere with other output loops.Sometimes, power supply Short circuit phenomenon occurs all the way for certain in output loop, and can not perceive the fault loop obvious fault by external environment, Now equipment is general is also running well, and corresponding protection circuit is also not turned on protecting a certain in work, but external equipment Short circuit occurs for road, so as to cause power source internal temperature to raise rapidly, beyond the requirement of security regulations, power supply is remained at pole Worked under high-temperature, add the loss of source element, overheat operation ultimately results in power supply damage, or even trigger fire etc..

Utility model content

In view of the shortcomings of the prior art, the utility model provides a kind of power supply short-circuit protection circuit.

A kind of power supply short-circuit protection circuit, including power source protective module, the power source protective module include overcurrent protection mould Block and short circuit protection module；The two ends of overcurrent protection module and short circuit protection module are all anti-with power supply output module, power supply respectively Present module connection；The power supply output module is connected with power transfer module, the power transfer module and energy supply control module It is connected, the power supply feedback module is connected with the energy supply control module.

The short circuit protection module includes PMOS Q1, triode Q2Q3Q4, diode D1D2D3, electric capacity C1 and resistance R1、R2、R3、R4、R5、R6、R7、R8、R9；PMOS driving circuit by triode Q2 colelctor electrode by connecting resistance R3, then PMOS Q1 is driven with R1 partial pressures, triode Q2 grounded collector, base stage is contacted and power supply by resistance R4 diodes D2 Feedback circuit is connected with power supply bleeder circuit.

The principle of the utility model control power supply output is as follows：When electrical equipment is in running order, power supply normal work is protected Circuit does not work, inactivity consumption etc..When short circuit occurs for power circuit, electric voltage exception caused by short circuit starts protection circuit Work, and failure is fed back into the feedback circuit of power supply, the control module of power supply is transferred to by the feedback circuit of power supply, is closed The output module of power supply, so as to reach stopping element manipulation, output of cutting off the electricity supply, protect power circuit components do not burn and Overheat, the situation that high temperature and blast are burnt does not occur.

Beneficial effect：The utility model is realized in the power module of power-supply system, and the protection circuit of neotectonics is direct It is embedded into original current supply circuit module, by feedback, realizes defencive function by original energy supply control module, it is to avoid electricity consumption Device loss caused by causing device damage, component temperature too high when equipment and short-circuit power source internal, protection electrical equipment and electricity The normal lasting work of source circuit.

Brief description of the drawings

Fig. 1 is modular structure schematic diagram of the present utility model；

Fig. 2 is the circuit theory diagrams of short circuit protection module in the utility model.

Embodiment

The utility model is described further with specific embodiment below in conjunction with the accompanying drawings.

Embodiment 1

As shown in figure 1, energy supply control module is connected with power transfer module, power supply feedback module respectively, power supply output mould Block is connected with power transfer module, power source protective module, output power supply module respectively.Externally fed module provides required civil power To Power Entry Module, the voltage electricity of specification needed for civil power is converted into electrical equipment by energy supply control module, power transfer module Stream, is exported by power supply output module and is used to electrical equipment；If there is abnormal, power source protective module inspection in electrical equipment in electric operation Exception is measured, energy supply control module is fed back to by power supply feedback module, power supply is closed, electrical equipment is protected, while controlling output mould Block disconnects output loop.

As shown in Fig. 2 the present invention includes short circuit protection module in fig. 2, triode Q2, voltage-stabiliser tube ZD1, electric capacity are utilized C1 and resistance R3, R4, R5 construction short-circuit protection circuit, wherein resistance R3, R4 is respectively triode Q2 emitter stage, base bias Resistance.Triode Q1, resistance R1, R2 are the partial circuit in power supply output module；Triode Q3, optocoupler PC1 feed back for power supply Partial circuit in module.Triode Q2 emitter stage is grounded by connecting voltage-stabiliser tube ZD1 and electric capacity C1 parallel circuit, three poles Pipe Q2 base stage is connected by resistance with FET Q1, and triode Q2 colelctor electrode passes through resistance R5 and the feedback circuit of power supply It is connected.FET Q1 grid is connected by resistance R2, R3 and triode Q2 emitter stage.Due to triode Q2 current collection Pole is connected to the feedback circuit of power supply, so being the break-make of controllable triode by voltage.When the output module of power supply occurs Short circuit, feeds back to voltage signal the feedback circuit of power supply, signal is given power supply by feedback circuit by the conducting of triode Control chip, is cut off the electricity supply output by the control module of power supply.

Fig. 2 operation principle is：When input VDC it is upper electric after R2, R7 partial pressure obtain it is electric after with Q3 combinations of states pass through diode D2 and resistance R4 drive triode Q2, because C1 needs to be charged by R5 after electricity on input, are reached in charging voltage When driving Q3 to diode D3 conducting voltage, Q2 is first turned on, R1 and R3 partial pressures driving PMOS, now exports Vout ends There is voltage output；The output end D poles of PMOS drive triode Q4 by resistance R8, so that C1 discharges, Q3 is still within cutting Only state, output state is kept；When output Vout ends have the short circuit to occur, Q4 ON-OFFs, C1 starts again at charging, when reaching D3 During cut-in voltage, Q3 conductings, D2 shut-offs, Q2 cut-offs, PMOS Q1 cut-offs, output shut-off.

Claims

1. a kind of power supply short-circuit protection circuit, including power source protective module, it is characterised in that the power source protective module included Flow protection module and short circuit protection module；The two ends of overcurrent protection module and short circuit protection module all export mould with power supply respectively Block, the connection of power supply feedback module；The power supply output module is connected with power transfer module, the power transfer module and power supply Control module is connected, and the power supply feedback module is connected with the energy supply control module.

2. power supply short-circuit protection circuit according to claim 1, it is characterised in that the short circuit protection module includes PMOS Pipe Q1, triode Q2 Q3 Q4, diode D1 D2 D3, electric capacity C1 and resistance R1, R2, R3, R4, R5, R6, R7, R8, R9； PMOS driving circuit drives PMOS Q1, triode by triode Q2 colelctor electrode by connecting resistance R3, then with R1 partial pressures Q2 grounded collector, base stage is contacted by resistance R4 diodes D2 to be connected with the feedback circuit and power supply bleeder circuit of power supply Connect.