CN205882679U - Protective circuit - Google Patents
Protective circuit Download PDFInfo
- Publication number
- CN205882679U CN205882679U CN201620019876.5U CN201620019876U CN205882679U CN 205882679 U CN205882679 U CN 205882679U CN 201620019876 U CN201620019876 U CN 201620019876U CN 205882679 U CN205882679 U CN 205882679U
- Authority
- CN
- China
- Prior art keywords
- comparison module
- module
- resistance
- protection circuit
- diode
- 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
Abstract
The utility model discloses a protective circuit, include: at least one first relatively module, at least one second be module, signal locking and level conversion module relatively, to every first relatively module, when should first relatively module detecting out an incoming signal and being lighter than first threshold value, should first relatively module and signal locking and level conversion module intercommunication, signal locking and level conversion module switch on, block power output, and when should first relatively module detecting out an incoming signal and being not less than first threshold value, this is first, and compare module and the signal locks and intercommunication of level conversion module breaks off, recovering power output, to every second module relatively, when this second comparison module detected out the 2nd incoming signal and is greater than the second threshold, this second is module and signal locking and level conversion module intercommunication relatively, and signal locking and level conversion module module switch on, blockade power output. This protective circuit simple structure, with low costs, stability height, safe and reliable, protection are effectual, are fit for being all kinds of switching power supply's protective circuit, improvement switching power supply's security and reliability.
Description
Technical field
This utility model relates to field of switch power, particularly relates to a kind of protection circuit.
Background technology
Direct-current switch power supply is an important branch of Development of Power Electronic Technology, and direct-current switch power supply is increasingly widely applied.Direct-current switch power supply includes the translation circuit that power electronic devices forms, corresponding control circuit and the protection circuit designed for protection Switching Power Supply inherently safe and payload security.
The protection circuit of direct-current switch power supply generally includes input undervoltage protection circuit, output overvoltage protection circuit, output overcurrent protection circuit, temperature protection circuit etc..
At present; in the design of direct-current switch power supply; it is all by individually designed for above-mentioned a few class protection circuits; input undervoltage protection circuit, output overvoltage protection circuit, output overcurrent protection circuit, temperature protection circuit are the most individually designed, and each several part uses different circuit modular structures, and the circuit therefore designed comparatively disperses; can not unified circuitry structure; being not easy to carry out equation design, and the digital circuit protecting the many employings of lock circuit to be similar to trigger etc realizes, circuit is more complicated.
Utility model content
In view of in prior art, all kinds of protection circuits of direct-current switch power supply are individually designed; each several part uses different circuit modular structures; therefore the circuit designed comparatively disperses; can not unified circuitry structure; it is not easy to carry out equation design; and the digital circuit protecting the many employings of lock circuit to be similar to trigger etc realizes, the problem that circuit is more complicated, it is proposed that this utility model is to provide a kind of protection circuit overcoming the problems referred to above or solving the problems referred to above at least in part.
This utility model provides a kind of protection circuit, including:
At least one first comparison module, at least one second comparison module, semaphore lock and level switch module；
For each first comparison module, when this first comparison module detects the first input signal less than first threshold, this first comparison module connects with semaphore lock and level switch module, semaphore lock and level switch module conducting, block power supply output, when this first comparison module detects the first input signal not less than first threshold, this first comparison module disconnects with the connection of semaphore lock and level switch module, recovers power supply output；
For each second comparison module, when this second comparison module detects the second input signal more than Second Threshold, this second comparison module connects with semaphore lock and level switch module, semaphore lock and level switch module conducting, block power supply output.
Wherein, for each first comparison module, this first comparison module includes the first switching diode, second switch diode, the first Zener diode, the second Zener diode, the first resistance, the second resistance.
Preferably,
The negative pole of the first switching diode and the negative pole of the first Zener diode connect, and the positive pole of the first switching diode and the first input signal connect；
The positive pole of the first Zener diode is connected with the negative pole of second switch diode, and is connected to zero level by the first resistance；
The positive pole of second switch diode and the positive pole of the second Zener diode connect；
The negative pole of the second Zener diode is connected with the base stage of semaphore lock and the PNP triode of level switch module, and be connected to the emitter-base bandgap grading of PNP triode by the second resistance and logic voltage provides point, and it is connected to the silicon controlled anode of semaphore lock and level switch module by the 4th resistance of semaphore lock and level switch module.
Wherein, for each second comparison module, this second comparison module includes potentiometer, the first electric capacity, comparator, the 3rd switching diode, the 3rd resistance, the second electric capacity.
Preferably,
One end of potentiometer connects datum, and the other end connects zero level, and centre tap connects the negative terminal of comparator；
The anode of comparator and the second input signal connect, and the outfan of comparator and the positive pole of the 3rd switching diode connect；
The negative pole of the 3rd switching diode is connected with the silicon controlled trigger electrode of semaphore lock and level switch module, and is connected to zero level by the 3rd resistance；
First electric capacity is in parallel with potentiometer；
Second electric capacity and the 3rd resistor coupled in parallel.
Wherein, semaphore lock and level switch module include controllable silicon, the 4th resistance, PNP triode, the 5th resistance, the 3rd electric capacity.
Preferably,
Silicon controlled anode is connected to negative pole and the base stage of PNP triode of the second Zener diode of the first comparison module by the 4th resistance；
The negative pole of the 3rd switching diode of silicon controlled trigger electrode and the second comparison module connects；
The colelctor electrode of PNP triode is connected to zero level by the 5th resistance；
The base stage of PNP triode is connected to the negative pole of the second Zener diode of the first comparison module；
3rd electric capacity and the 5th resistor coupled in parallel.
Wherein, the first input signal includes: voltage, electric current, temperature.
Wherein, the second input signal includes: voltage, electric current, temperature.
Preferably, in parallel between the first comparison module.
Preferably, in parallel between the second comparison module.
This utility model has the beneficial effect that:
Terminal by means of this utility model embodiment, solve all kinds of protection circuits of direct-current switch power supply in prior art individually designed, each several part uses different circuit modular structures, therefore the circuit designed comparatively disperses, can not unified circuitry structure, it is not easy to carry out equation design, and the digital circuit protecting the many employings of lock circuit to be similar to trigger etc realizes, the problem that circuit structure is more complicated, pass through this utility model, all kinds of protection circuits are attached in a protection circuit, this protection circuit simple in construction, low cost, stability is high, safe and reliable, protected effect is good, it is suitable for doing the protection circuit of all kinds of Switching Power Supply, improve the safety and reliability of Switching Power Supply.
Described above is only the general introduction of technical solutions of the utility model, in order to better understand technological means of the present utility model, and can be practiced according to the content of description, and in order to above and other objects, features and advantages of the present utility model can be become apparent, below especially exemplified by detailed description of the invention of the present utility model.
Accompanying drawing explanation
By reading the detailed description of hereafter preferred implementation, various other advantage and benefit those of ordinary skill in the art be will be clear from understanding.Accompanying drawing is only used for illustrating the purpose of preferred implementation, and is not considered as restriction of the present utility model.And in whole accompanying drawing, it is denoted by the same reference numerals identical parts.In the accompanying drawings:
Fig. 1 is the structural representation of the protection circuit of this utility model embodiment；
Fig. 2 is the structural representation of multiple first comparison modules of this utility model embodiment；
Fig. 3 is the structural representation of multiple second comparison modules of this utility model embodiment；
Fig. 4 is the electrical block diagram of the first comparison module of this utility model embodiment；
Fig. 5 is the electrical block diagram of the second comparison module of this utility model embodiment；
Fig. 6 is semaphore lock and the electrical block diagram of level switch module of this utility model embodiment；
Fig. 7 is the structural representation of the Switching Power Supply main circuit of this utility model embodiment；
Fig. 8 is the detailed construction schematic diagram of the protection circuit of this utility model embodiment.
Detailed description of the invention
It is more fully described the exemplary embodiment of the disclosure below with reference to accompanying drawings.Although accompanying drawing showing the exemplary embodiment of the disclosure, it being understood, however, that may be realized in various forms the disclosure and should not limited by embodiments set forth here.On the contrary, it is provided that these embodiments are able to be best understood from the disclosure, and complete for the scope of the present disclosure can be conveyed to those skilled in the art.
Below in conjunction with accompanying drawing and embodiment, this utility model is further elaborated.Should be appreciated that specific embodiment described herein, only in order to explain this utility model, does not limit this utility model.
Protection circuit embodiment
According to embodiment of the present utility model, provide a kind of protection circuit, Fig. 1 is the structural representation of the protection circuit of this utility model embodiment, as shown in Figure 1, protection circuit according to this utility model embodiment includes: at least one first comparison module (the first comparison module 1, first comparison module 2, ..., first comparison module N), at least one second comparison module (the second comparison module 1, second comparison module 2, ..., second comparison module M), semaphore lock and level switch module 10, hereinafter the modules of this utility model embodiment is described in detail.
For each first comparison module, this first comparison module is connected with semaphore lock and level switch module 10, when this first comparison module detects the first input signal less than first threshold, this first comparison module connects with semaphore lock and level switch module, semaphore lock and level switch module conducting, block power supply output, owing to the first input signal is continually changing, when this first comparison module detects the first input signal not less than first threshold, this first comparison module disconnects with the connection of semaphore lock and level switch module, recovers power supply output.
First input signal can be: voltage, electric current, temperature.
Parallel connection between each first comparison module.
First threshold can change the first Zener diode in the first comparison module according to actual needs, the second Zener diode is arranged, and this utility model embodiment does not limit.
Assume that protection circuit has three the first comparison modules, first comparison module 1, first comparison module 2 and the first comparison module 3, first comparison module 1, between first comparison module 2 and the first comparison module 3 (as shown in Figure 2) the most in parallel, wherein, the input signal of the first comparison module 1 correspondence is input voltage, first threshold is the first input voltage threshold value pre-set, then for the first comparison module 1, first comparison module 1 is connected with semaphore lock and voltage transformation module 10, first comparison module 1 detects when input voltage is less than the first input voltage threshold value, first comparison module 1 connects with semaphore lock and voltage transformation module, semaphore lock and level switch module conducting, block power tube drives signal, block power supply output, play the effect of protection power supply；Owing to input voltage is continually changing, when the first comparison module 1 detects that input voltage is not less than the first input voltage threshold value, the first comparison module 1 disconnects with the connection of semaphore lock and level switch module, recovers power supply output.The input signal of the first comparison module 2 correspondence is input current, first threshold is the first input current threshold value pre-set, then for the first comparison module 2, first comparison module 2 is connected with semaphore lock and level switch module 10, first comparison module 2 detects when input current is less than the first input current threshold value, first comparison module 2 connects with semaphore lock and level switch module, semaphore lock and level switch module conducting, block power tube drives signal, block power supply output, play the effect of protection power supply, owing to input current is continually changing, when the first comparison module 2 detects that input current is not less than the first input current threshold value, first comparison module 2 disconnects with the connection of semaphore lock and level switch module, recover power supply output；The input signal of the first comparison module 3 correspondence is input temp, first threshold is the first input temp threshold value pre-set, then for the first comparison module 3, first comparison module 3 is connected with semaphore lock and level switch module 10, first comparison module 3 detects when input temp is less than the first input temp threshold value, first comparison module 3 connects with semaphore lock and level switch module, semaphore lock and level switch module conducting, block power tube drives signal, block power supply output, play the effect of protection power supply, owing to input temp is continually changing, when the first comparison module 3 detects that input temp is not less than the first input temp threshold value, first comparison module 3 disconnects with the connection of semaphore lock and level switch module, recover power supply output.
For each second comparison module, this second comparison module is connected with semaphore lock and level switch module 10, when this second comparison module detects the second input signal more than Second Threshold, this second comparison module connects with semaphore lock and level switch module, semaphore lock and level switch module conducting, block power supply output.
Second input signal can be: voltage, electric current, temperature.
Parallel connection between each second comparison module.
Second Threshold can be arranged according to actual needs, and this utility model embodiment does not limit.
Assume that protection circuit has three the second comparison modules, second comparison module 1, second comparison module 2 and the second comparison module 3, second comparison module 1, between second comparison module 2 and the second comparison module 3 (as shown in Figure 3) the most in parallel, wherein, the input signal of the second comparison module 1 correspondence is voltage, Second Threshold is the second voltage threshold pre-set, then for the second comparison module 1, second comparison module 1 is connected with semaphore lock and level switch module 10, second comparison module 1 detects when input voltage is more than the second voltage threshold, second comparison module 1 connects with semaphore lock and level switch module, semaphore lock and level switch module conducting, block power tube drives signal, thus block power supply output, protection load；The input signal of the second comparison module 2 correspondence is electric current; Second Threshold is the second current threshold pre-set; then for the second comparison module 2; second comparison module 2 is connected with semaphore lock and level switch module 10, and the second comparison module 2 detects when input current is more than the second current threshold, and the second comparison module 2 connects with semaphore lock and level switch module; semaphore lock and level switch module conducting; block power tube drives signal, thus blocks power supply output, protects power supply；The input signal of the second comparison module 3 correspondence is temperature, Second Threshold is the second temperature threshold pre-set, then for the second comparison module 3, second comparison module 3 is connected with semaphore lock and level switch module 10, and the second comparison module 3 detects when input temp is more than the second temperature threshold, and the second comparison module 3 connects with semaphore lock and level switch module, semaphore lock and level switch module conducting, block power tube drives signal, thus blocks power supply output, reduces the temperature of input point.
Pass through this utility model; all kinds of protection circuits are attached in a protection circuit; this protection circuit simple in construction, low cost, stability are high, safe and reliable, protected effect is good, are suitable for doing the protection circuit of all kinds of Switching Power Supply, improve the safety and reliability of Switching Power Supply.
Fig. 4 is the electrical block diagram of the first comparison module of this utility model embodiment, first comparison module includes the first switching diode, second switch diode, first Zener diode, second Zener diode, first resistance, second resistance, as shown in Figure 4, by switching diode D9 (the first switching diode the most mentioned above), Zener diode VD1 (the first Zener diode the most mentioned above), resistance R2 (the first resistance the most mentioned above), switching diode D10 (second switch diode the most mentioned above), Zener diode VD2 (the second Zener diode the most mentioned above), undervoltage detection circuit that resistance R3 (the second resistance the most mentioned above) is constituted and electromotive force comparison circuit, annexation is as follows:
The negative pole of the first switching diode D9 and the negative pole of the first Zener diode VD1 connect, and the positive pole of the first switching diode D9 and the first input signal connect；
The positive pole of the first Zener diode VD1 is connected with the negative pole of second switch diode D10, and is connected to zero level by the first resistance R2；
The positive pole of second switch diode D10 and the positive pole of the second Zener diode VD2 connect；
The negative pole of the second Zener diode VD2 is connected with the base stage of semaphore lock and the PNP triode of level switch module, and be connected to the emitter-base bandgap grading of PNP triode by the second resistance R3 and logic voltage provides point, and it is connected to the silicon controlled anode of semaphore lock and level switch module by the 4th resistance R4 of semaphore lock and level switch module.
Fig. 5 is the electrical block diagram of the second comparison module of this utility model embodiment, second comparison module includes potentiometer, first electric capacity, comparator, 3rd switching diode, 3rd resistance, second electric capacity, as shown in Figure 5, by potentiometer RP1 (potentiometer the most mentioned above), electric capacity C5 (the first electric capacity the most mentioned above), comparator U2 (comparator the most mentioned above), switching diode D11 (the 3rd switching diode the most mentioned above), resistance R5 (the 3rd resistance the most mentioned above), the adjustable comparator circuit of comparison threshold value that electric capacity C7 (the second electric capacity the most mentioned above) is constituted, annexation is as follows:
One end of potentiometer RP1 connects datum, and the other end connects zero level, and centre tap connects the negative terminal of comparator U2；
The anode of comparator U2 and the second input signal connect, and the outfan of comparator U2 and the positive pole of the 3rd switching diode D11 connect；
The negative pole of the 3rd switching diode D11 is connected with the silicon controlled trigger electrode of semaphore lock and level switch module, and is connected to zero level by the 3rd resistance R5；
First electric capacity C5 is in parallel with potentiometer RP1；
Second electric capacity C7 and the 3rd resistance R5 is in parallel.
Fig. 6 is semaphore lock and the electrical block diagram of level switch module of this utility model embodiment, semaphore lock and level switch module include controllable silicon, 4th resistance, PNP triode, 5th resistance, 3rd electric capacity, as shown in Figure 6, by controllable silicon TR1 (controllable silicon the most mentioned above), resistance R4 (the 4th resistance the most mentioned above), PNP triode VT3 (PNP triode the most mentioned above), resistance R6 (the 5th resistance the most mentioned above, protection locking that electric capacity C8 (the 3rd electric capacity the most mentioned above) is constituted and level shifting circuit, annexation is as follows:
The anode of controllable silicon TR1 is connected to the base stage of PNP triode VT3 by the 4th resistance R4；
The negative pole of the trigger electrode of controllable silicon TR1 and the 3rd switching diode of the second comparison module connects；
The colelctor electrode of PNP triode VT3 is connected to zero level by the 5th resistance R6；
The base stage of PNP triode VT3 is connected to the negative pole of the second Zener diode of the first comparison module；
3rd electric capacity C8 and the 5th resistance R6 is in parallel.
This utility model embodiment overcome present in prior art each design protection relative distribution such as the protection of direct-current switch power supply input undervoltage, output over-voltage protection, output overcurrent protection circuit, circuit can not multiplexing, be not easy to protect way extension；Lock circuit uses problem and the defect of digital flip-flop circuit; a kind of general protective circuit structure for direct-current switch power supply input undervoltage, output overvoltage, output overcurrent etc. is provided; this structure makes circuit devcie reusability between various protection circuit high; protection locking design is simple; protection circuit extension becomes easy, and Protection parameters easily changes.
This utility model embodiment for convenience of description, this utility model is described as a example by first comparison module, two the second comparison modules, but meets the circuit of this utility model annexation still in protection domain of the present utility model.
Below in conjunction with the accompanying drawings the technical scheme of this utility model embodiment is described in further detail:
Fig. 7 is the structural representation of the Switching Power Supply main circuit of this utility model embodiment; Fig. 8 is the detailed construction schematic diagram of the protection circuit of this utility model embodiment; wherein; main power circuit is double-transistor flyback formula switching power circuit; pwm chip is TL494, is not limited thereto power circuit structure and this pwm chip in actual application.
In conjunction with Fig. 7, main power circuit part is illustrated, the sampled point of main clear and definite protection circuit, for aid illustration part of the present utility model.As it is shown in fig. 7, commutation diode D1, D2, D3, D4 and electrochemical capacitor C1 are current rectifying and wave filtering circuit, AC-input voltage is transformed to the DC voltage of pulsation；Metal-oxide-semiconductor VT1, VT2, fast recovery diode D5, D6, high frequency transformer T1, fast recovery diode D7, electrochemical capacitor C3 constitute the switch change-over main power circuit of double-transistor flyback, and Main_out nexus is main road output voltage.When metal-oxide-semiconductor VT1, VT2 open, fast recovery diode D7 reversely ends, and the busbar voltage after rectifying and wave-filtering is that the former limit inductance of T1 is charged, and stores energy；When metal-oxide-semiconductor VT1, VT2 close, transformer secondary output winding polarity overturns, and fast recovery diode D7 is open-minded, and the energy that inductance stores is fed to output by secondary windings.Pwm chip sampling and outputting voltage in Fig. 8 and send pulse drive signal through isolation rear drive metal-oxide-semiconductor VT1 and VT2, plays the control action of regulated output voltage by closed loop regulation.Wherein TR (current transformer), resistance R1, electric capacity C2 constitute primary current sample circuit, because out-put supply is constant pressure source, be equivalent to sampling for output electric current, simply there is certain proportionate relationship with output size of current in the size of current of this point sampling；The auxiliary winding of high frequency transformer T1 and fast recovery diode D8, electrochemical capacitor C4 constitute accessory power supply, on the one hand power for the pwm chip TL494 in Fig. 8, on the other hand as the sampled point of bus under-voltage protection.Wherein Main_out nexus is the sampled point for output voltage protection, can be input to protection circuit below (in this enforcements explanation directly using output voltage as protecting sampled voltage) after this voltage or this voltage being carried out dividing potential drop according to protection magnitude of voltage size.
Fig. 8 is the structural representation of protection circuit, as shown in Figure 8, switching diode D9, Zener diode VD1, resistance R2, switching diode D10, Zener diode VD2, resistance R3 constitutes the first comparison circuit, potentiometer RP1, electric capacity C5, comparator U2, switching diode D11, resistance R5, adjustable second comparison circuit 1 of comparison threshold value that electric capacity C7 is constituted, potentiometer RP2, electric capacity C6, comparator U3, switching diode D12, resistance R5, electric capacity C7 constitutes the second comparison circuit 2, controllable silicon TR1, resistance R4, PNP triode VT3, resistance R6, electric capacity C8 constitutes semaphore lock and level shifting circuit.
The structure chart of Fig. 8 is this utility model utility model point, and protection circuit is formed by with lower part, and input undervoltage detects and electromotive force compares, output overvoltage, excessively flow point set and compare, protecting locking and level conversion.The input of protection circuit derive from Fig. 7 three sampled points.Wherein switching diode D9, Zener diode VD1, resistance R2, switching diode D10, the undervoltage detection circuit of Zener diode VD2, resistance R3 composition and electromotive force comparison circuit；The adjustable comparator circuit of comparison threshold value that potentiometer RP1, electric capacity C5, comparator U2, switching diode D11, resistance R5, electric capacity C7 are constituted, potentiometer RP2, electric capacity C6, comparator U3, switching diode D12, resistance R5, electric capacity C7 constitute another and compare the adjustable comparator circuit of threshold value；The locking protection being made up of controllable silicon TR1, resistance R4, PNP triode VT3, resistance R6, electric capacity C8 and level shifting circuit；The signal that protection circuit finally exports goes the dead zone function pin (4) controlling U1 (TL494) to realize.Described from module above, the level shifting circuit that three kinds of protections common parts VT3, C8, R6 are constituted；Output overvoltage and output overcurrent have shared R5, C7, TR1, R4 lock circuit the most simultaneously；Similar voltage protection, the comparison circuit part of current protection can be extended, and increase protection way.
TL494 chip is Control of Voltage cake core, 12 feet are energization pins, 14 feet are the voltage stabilizing output pin of 5V, and 9 feet are pulse output pin, and 4 feet are dead zone function pin, when 4 foot inputs are for low level, 9 feet have normal pulse output, and power supply normally works, when 4 foot inputs are for high level, the pulse output of 9 feet is just blocked, thus closes power supply output.
In terms of input undervoltage, output overvoltage and output overcurrent three, this utility model embodiment is described below.
Input undervoltage: during input undervoltage; the electric current of switch power supply power tube and transformator can increase; when working more than the regular hour; can because crossing the damage of thermally-induced power switch pipe or the damage of transformator, voltage low to a certain extent time, also result in Switching Power Supply and can not carry out full power output; the under-voltage protection of power input to be carried out; closing switch power supply exports, and voltage to be entered recovers normal, and power supply should be able to recover output automatically.In conjunction with Fig. 7 and Fig. 8, when AC-input voltage is normal, busbar voltage after rectifying and wave-filtering is higher, on high frequency transformer T1 auxiliary winding, Zener diode VD1 can be punctured by the voltage Vol_aux after rectifying and wave-filtering, resistance R2 has voltage, due to the existence of this voltage, switching diode D10, stabilivolt VD2, PNP triode VT3 can not turn on, the current collection of VT3 extremely low level, the level of 4 feet of input U1 is low level, and controller normally works；When AC-input voltage is too low, busbar voltage is relatively low, stabilivolt VD1 can not be punctured by the magnitude of voltage of the Vol_aux (the first input signal the most mentioned above) after T1 auxiliary winding rectifying and wave-filtering, therefore resistance R2, switching diode D10, stabilivolt VD2, PNP triode VT3 form path, VT3 saturation conduction, current collection extremely high pressure, makes the level of 4 feet of input U1 be blocked close to 5V, the pulse output of 9 feet；When input undervoltage disappears when, stabilivolt VD1 is the most breakdown, and PNP triode VT3 becomes again cut-off state, drives signal normally to export, and power supply normally works, and therefore input undervoltage protection can self-recoverage in the case of not power-off.
Output overvoltage: when Switching Power Supply output overvoltage, illustrates that Switching Power Supply self occurs in that fault, and load can be caused expendable infringement, overvoltage protection to be done by overvoltage output, turns off output, and this kind of protection needs locking, turns back on after inspection.In conjunction with Fig. 7 and Fig. 8, when main output voltage is normal, output voltage Main_out voltage is less than the reference voltage of comparator U2 negative input end, and comparator is output as low level, D11 is not turned on, the triggering pin of IGCT is low level, and IGCT is obstructed, the base stage nonpassage of PNP triode VT3, it is not turned on, VT3 colelctor electrode obtains low level, and the level of 4 feet of input U1 is low level, drives output normal；When main output overvoltage; output voltage Main_out voltage (the second input signal the most mentioned above) is higher than the reference voltage of comparator negative terminal input; comparator U1 is output as high level; D11 turns on; the triggering end level of TR1 is high level; therefore controllable silicon TR1 conducting; VT3 is also switched on; output driving is blocked, and owing to TR1 has latching effect, fault-signal disappears; circuit all will be in protection; therefore output over-voltage protection has lock function, it is necessary to restart power supply, could recover output under non-failure conditions.
Output overcurrent: during switch power source output overcurrent, illustrates that load there occurs problem, now must turn off Switching Power Supply output, and lock, turn back on, otherwise Switching Power Supply can be caused damage after inspection.In conjunction with Fig. 7 and Fig. 8, when main output is only flowed, for detecting the reference voltage less than comparator U3 negative input end of the voltage Cur_sen after the former limit of transformator T1 lays out current transformer conditioning, comparator is output as low level, D12 is not turned on, the triggering pin of IGCT is low level, and IGCT is obstructed, the base stage nonpassage of PNP triode VT3, it is not turned on, VT3 colelctor electrode obtains low level, and the level of 4 feet of input U1 is low level, drives output normal；When main output overcurrent; for detecting the reference voltage higher than the input of comparator negative terminal of the voltage Cur_sen voltage after the former limit of transformator T1 lays out current transformer conditioning; comparator U1 is output as high level; D11 turns on; the triggering end level of TR1 is high level; therefore controllable silicon TR1 conducting; VT3 is also switched on; output driving is blocked, and owing to TR1 has latching effect, fault-signal disappears; circuit all will be in protection; therefore output overcurrent protection has lock function, it is necessary to restart power supply, could recover output under non-failure conditions.
Temperature protection circuit is for the protection circuit preventing the device that the caloric value such as switching tube or transformator is big from arranging because of the too high damage of temperature, and design principle and structure have been described above, and repeat no more here.
The circuit of this utility model embodiment can revise Protection parameters when migration utilizes, such as, revise stabilivolt VD1 and the VD2 magnitude of voltage of under-voltage detection part, adjustable under-voltage protection value size；Threshold size for overvoltage protection and overcurrent protection can regulate, can extend similar overvoltage, cross flow ratio compared with protection circuit way.
Use the protection circuit of this utility model embodiment; compared with prior art; this utility model takes full advantage of switching diode, audion, Zener diode and silicon controlled characteristic; the general protective circuit structure of design; input undervoltage, output overvoltage, output overcurrent protection etc. can be attached in one piece of core circuit; changed into concentrating by dispersion, three kinds of protection common sparing devices；Utilize the latching effect after control machines to replace the lock circuit structure of flip-flop type, it is achieved protection locking function, make circuit become simple；Based on this kind of protection circuit structure; the parameter of the element be also equipped with protecting way easily to extend, only changing employing is not required to change circuit structure and just can reuse; making protecting circuit designed possess the advantage of equation formula design, this protection circuit is highly suitable in the direct-current switch power supply of different capacity grade.
Obviously, those skilled in the art can carry out various change and modification without deviating from spirit and scope of the present utility model to this utility model.So, if these amendments of the present utility model and modification belong within the scope of this utility model claim and equivalent technologies thereof, then this utility model is also intended to comprise these change and modification.
In description mentioned herein, illustrate a large amount of detail.It is to be appreciated, however, that embodiment of the present utility model can be put into practice in the case of not having these details.In some instances, it is not shown specifically known method, structure and technology, in order to do not obscure the understanding of this description.
Similarly, it is to be understood that, one or more in order to simplify that the disclosure helping understands in each utility model aspect, in description to exemplary embodiment of the present utility model above, each feature of the present utility model is grouped together in single embodiment, figure or descriptions thereof sometimes.But, should not be construed to the method for the disclosure reflect an intention that this utility model the most required for protection requires feature more more than the feature being expressly recited in each claim.More precisely, as the following claims reflect, utility model aspect is all features less than single embodiment disclosed above.Therefore, it then follows claims of detailed description of the invention are thus expressly incorporated in this detailed description of the invention, the most each claim itself is as independent embodiment of the present utility model.
Those skilled in the art are appreciated that and the block combiner in embodiment can be become a module, and can put them into multiple submodule or subelement or sub-component in addition.In addition at least some in such feature and/or process or unit excludes each other, can use any combination that all features disclosed in this specification (including adjoint claim, summary and accompanying drawing) and so disclosed any method or all processes of client or unit are combined.Unless expressly stated otherwise, each feature disclosed in this specification (including adjoint claim, summary and accompanying drawing) can be replaced by the alternative features providing identical, equivalent or similar purpose.
In addition, those skilled in the art it will be appreciated that, although embodiments more described herein include some feature included in other embodiments rather than further feature, but the combination of the feature of different embodiment means to be within the scope of this utility model and form different embodiments.Such as, in the following claims, one of arbitrarily can mode the using in any combination of embodiment required for protection.
It should be noted that this utility model is illustrated rather than by above-described embodiment this utility model is limited, and those skilled in the art can design alternative embodiment without departing from the scope of the appended claims.In the claims, any reference marks that should not will be located between bracket is configured to limitations on claims.Word " comprises " and does not excludes the presence of the element or step not arranged in the claims.Word "a" or "an" before being positioned at element does not excludes the presence of multiple such element.This utility model by means of including the hardware of some different elements and can realize by means of properly programmed computer.If in the unit claim listing equipment for drying, several in these devices can be specifically to be embodied by same hardware branch.Word first, second and third use do not indicate that any order.Can be title by these word explanations.
Claims (11)
1. a protection circuit, it is characterised in that include,
At least one first comparison module, at least one second comparison module, semaphore lock and level switch module；
For each first comparison module, when this first comparison module detects the first input signal less than first threshold, this first comparison module connects with described semaphore lock and level switch module, described semaphore lock and level switch module conducting, block power supply output, when this first comparison module detects described first input signal not less than first threshold, this first comparison module disconnects with the connection of described semaphore lock and level switch module, recovers power supply output；
For each second comparison module, when this second comparison module detects the second input signal more than Second Threshold, this second comparison module connects with described semaphore lock and level switch module, described semaphore lock and level switch module conducting, block power supply output.
2. protection circuit as claimed in claim 1; it is characterized in that; for each first comparison module, this first comparison module includes the first switching diode, second switch diode, the first Zener diode, the second Zener diode, the first resistance, the second resistance.
3. protection circuit as claimed in claim 2, it is characterised in that
The negative pole of described first switching diode is connected with the negative pole of described first Zener diode, and the positive pole of described first switching diode is connected with described first input signal；
The positive pole of described first Zener diode is connected with the negative pole of described second switch diode, and is connected to zero level by described first resistance；
The positive pole of described second switch diode is connected with the positive pole of described second Zener diode；
The negative pole of described second Zener diode is connected with the base stage of described semaphore lock and the PNP triode of level switch module, and be connected to the emitter-base bandgap grading of described PNP triode by described second resistance, and it is connected to the silicon controlled anode of described semaphore lock and level switch module by the 4th resistance.
4. protection circuit as claimed in claim 1, it is characterised in that for each second comparison module, this second comparison module includes potentiometer, the first electric capacity, comparator, the 3rd switching diode, the 3rd resistance, the second electric capacity.
5. protection circuit as claimed in claim 4, it is characterised in that
One end of described potentiometer connects datum, and the other end connects zero level, and centre tap connects the negative terminal of described comparator；
The anode of described comparator is connected with described second input signal, and the outfan of described comparator is connected with the positive pole of described 3rd switching diode；
The described negative pole of the 3rd switching diode is connected with the silicon controlled trigger electrode of described semaphore lock and level switch module, and is connected to zero level by described 3rd resistance；
Described first electric capacity is in parallel with described potentiometer；
Described second electric capacity and described 3rd resistor coupled in parallel.
6. protection circuit as claimed in claim 1, it is characterised in that described semaphore lock and level switch module include controllable silicon, the 4th resistance, PNP triode, the 5th resistance, the 3rd electric capacity.
7. protection circuit as claimed in claim 6, it is characterised in that
Described silicon controlled anode is connected to negative pole and the base stage of described PNP triode of the second Zener diode of described first comparison module by described 4th resistance；
Described silicon controlled trigger electrode is connected with the negative pole of the 3rd switching diode of described second comparison module；
The colelctor electrode of described PNP triode is connected to zero level by described 5th resistance；
The base stage of described PNP triode is connected to the negative pole of the second Zener diode of described first comparison module；
Described 3rd electric capacity and described 5th resistor coupled in parallel.
8. the protection circuit as according to any one of claim 1 to 7, it is characterised in that described first input signal includes: voltage, electric current, temperature.
9. the protection circuit as according to any one of claim 1 to 7, it is characterised in that described second input signal includes: voltage, electric current, temperature.
10. the protection circuit as according to any one of claim 1 to 7, it is characterised in that in parallel between the first comparison module.
11. protection circuits as according to any one of claim 1 to 7, it is characterised in that in parallel between the second comparison module.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620019876.5U CN205882679U (en) | 2016-01-08 | 2016-01-08 | Protective circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620019876.5U CN205882679U (en) | 2016-01-08 | 2016-01-08 | Protective circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN205882679U true CN205882679U (en) | 2017-01-11 |
Family
ID=57686343
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201620019876.5U Active CN205882679U (en) | 2016-01-08 | 2016-01-08 | Protective circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN205882679U (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108574259A (en) * | 2018-06-22 | 2018-09-25 | 深圳市高胜科研电子有限公司 | A kind of protective device of direct current supply, system and control method |
| TWI644495B (en) * | 2017-11-24 | 2018-12-11 | 和碩聯合科技股份有限公司 | Input protection circuit |
| CN109245051A (en) * | 2018-08-28 | 2019-01-18 | 出门问问信息科技有限公司 | A kind of supply convertor |
| CN112725833A (en) * | 2020-12-31 | 2021-04-30 | 珠海格力电器股份有限公司 | Electrolysis control circuit, control method and disinfectant manufacturing device |
| CN114019373A (en) * | 2021-11-01 | 2022-02-08 | 常州机电职业技术学院 | Efficient servo motor automatic test system |
-
2016
- 2016-01-08 CN CN201620019876.5U patent/CN205882679U/en active Active
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI644495B (en) * | 2017-11-24 | 2018-12-11 | 和碩聯合科技股份有限公司 | Input protection circuit |
| CN108574259A (en) * | 2018-06-22 | 2018-09-25 | 深圳市高胜科研电子有限公司 | A kind of protective device of direct current supply, system and control method |
| CN109245051A (en) * | 2018-08-28 | 2019-01-18 | 出门问问信息科技有限公司 | A kind of supply convertor |
| CN112725833A (en) * | 2020-12-31 | 2021-04-30 | 珠海格力电器股份有限公司 | Electrolysis control circuit, control method and disinfectant manufacturing device |
| CN112725833B (en) * | 2020-12-31 | 2023-10-24 | 珠海格力电器股份有限公司 | Electrolytic control circuit, control method and disinfectant manufacturing device |
| CN114019373A (en) * | 2021-11-01 | 2022-02-08 | 常州机电职业技术学院 | Efficient servo motor automatic test system |
| CN114019373B (en) * | 2021-11-01 | 2022-06-07 | 常州机电职业技术学院 | Efficient servo motor automatic test system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN205882679U (en) | Protective circuit | |
| CN103683931B (en) | A kind of power-switching circuit | |
| CN203289341U (en) | Flyback switch power supply circuit | |
| CN102013802B (en) | BOOST circuit with short circuit protection function | |
| CN104283441B (en) | A kind of dc source and the method that dc source is provided | |
| CN202652595U (en) | LED drive circuit and LED circuit comprising same | |
| CN103545803B (en) | Device power supply (DPS) interface circuit protection device | |
| CN105610129B (en) | Over voltage protects control circuit | |
| CN107845998B (en) | Input power supply health detection and management circuit in power supply parallel redundancy system | |
| CN103474965A (en) | Low-cost alternating-current input overvoltage protection circuit and switching power supply | |
| CN106961094B (en) | The system of input undervoltage and overvoltage protection is provided for supply convertor | |
| CN205453099U (en) | Sampling circuit and mistake, undervoltage protection control circuit | |
| CN203787956U (en) | Surge voltage suppression circuit | |
| CN105337263A (en) | Output overvoltage protection circuit and method for DC/DC converter | |
| CN110994567A (en) | Direct current power grid fault current controller | |
| CN105680839B (en) | A kind of three level driving circuit of I types | |
| WO2023004952A1 (en) | Vehicle-mounted power supply circuit, and vehicle | |
| CN108539968A (en) | Switching Power Supply and its control method | |
| CN203398768U (en) | Low-cost AC input overvoltage protection circuit and switching power supply | |
| CN104319739A (en) | DC surge voltage clamping circuit with reversal connection protection | |
| CN102711323B (en) | LED lamp drive circuit | |
| CN204118704U (en) | A kind of input abnormal pressure overvoltage crowbar | |
| CN107658857A (en) | A kind of switch power over-voltage protection circuit and method | |
| CN203406776U (en) | DC power supply | |
| CN204118706U (en) | A kind of multiple-channel output high reliability overvoltage crowbar |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant |