A kind of Switching Power Supply hiccup protections and delay protection circuit
Technical field
The invention relates to a kind of Switching Power Supply hiccup protections and delay protection circuit.
Background technology
In the middle of the power supply practical application, a lot of protections all need to make the circuit of having the hiccups.Prior art is general adopt with each independently protective circuit do respectively the circuit of having the hiccups and maybe all protective circuit signals all be aggregated in the middle of the circuit of having the hiccups.The former circuit is very complicated, and the latter is relatively simple, but the latter still needs to solve the problem that signal is arranged in pairs or groups and sequential cooperates between various protective circuits, and not only design difficulty is large, and the cost of the power supply that increases and the difficulty of production, has reduced the reliability of power supply.And final power supply also needs to do the protection delay circuit, so also exists every kind of protective circuit to make the complexity of protection time-delay.
Summary of the invention
For above-mentioned technological deficiency, the invention provides a kind of Switching Power Supply hiccup protections and delay protection circuit, has solved that protection is had the hiccups and the time-delay demand of protective circuit, and circuit structure is simple.
It is as described below that the invention solves the technical scheme that its technical problem adopts: a kind of Switching Power Supply hiccup protections and delay protection circuit, it is characterized in that, and comprising:
The power work accumulator, this circuit be follow-up protection have the hiccups and shut down the time-delay prepare, delay circuit power supply and other circuit separately, can misoperation when having guaranteed machine, after the delay circuit onset, do not change the delay circuit operating state because of external status;
The power work state detection circuit, this circuit realizes namely finishing by a delay circuit delay protection of all circuit, so the signal that detects must be that power work just exists, and the signal that power supply is not worked and just disappeared;
The delay circuit action delay circuit that comes into force, this circuit are realized power supply purpose that delay circuit just moves after the shutdown really, the misoperation when avoiding power input voltage or load variations to cause that power supply is larger adjusting;
Relatively confirm to carry out shutdown circuit, the delay circuit action delay comes into force behind the circuit, this circuit operation, power supply shutdown;
Turning-off delay circuit during this circuit is carried out, is in off-mode, avoids occurring instantaneous start or repeated switching, reaches the purpose that protection is had the hiccups regularly and protected time-delay.
Described power work accumulator is made of diode D22, resistance R 24 and capacitor C 17; Described power work state detection circuit is made of resistance R 88, resistance R 58 and triode Q15; The described delay circuit action delay circuit that comes into force is made of resistance R 39 and capacitor C 24; Described relatively affirmation is carried out shutdown circuit and is made of triode Q14; Described turning-off delay circuit is made of capacitor C 17 and resistance R 51, and behind the power work, the DRA energy is stored in the capacitor C 17 by diode D22, resistance R 24; DRA passes through resistance R 88, triode Q15, resistance R 58 to triode Q14; After the DRA no-output, triode Q15 is not open-minded, and the DRA energy on the capacitor C 17 gives capacitor C 24 chargings by resistance R 39, after capacitor C 24 voltages reach the door capable of being opened voltage limit Gth of triode Q14, triode Q14 is open-minded, and after the power supply shutdown, the energy of capacitor C 17 is by resistance R 51 discharges.
Described power work state detection circuit replaces with the mos pipe.
Described relatively affirmation is carried out shutdown circuit and is replaced with comparator.
The invention according to said structure; its beneficial effect is; the invention is had the hiccups protection and is protected time-delay together integrated, has namely finished the delay circuit of whole all protections of power supply and the circuit of having the hiccups by a simple delay circuit, and circuit structure is simpler.And the sequencing control problem of the time time-delay circuit operation that do not have power work, greatly simplified design sequential difficulty.Avoid the design iterations delay circuit, reduced the power supply cost, increased power supply reliability.
Description of drawings
Below in conjunction with accompanying drawing and embodiment the invention is described further.
Fig. 1 is the invention circuit structure block diagram;
Fig. 2 is the invention embodiment one circuit theory diagrams;
Fig. 3 is the invention embodiment two circuit theory diagrams;
Fig. 4 is the invention embodiment three-circuit schematic diagram.
Embodiment
As shown in Figure 1, a kind of Switching Power Supply hiccup protections and delay protection circuit comprise five circuit, the one, and power work accumulator, power supply only have later on ability energy storage of work, have the hiccups and shut down to delay time for later protection and prepare; Its delay circuit power supply and other circuit separately can misoperations when having guaranteed machine.The 2nd, the power work state detection circuit, it guarantee a delay circuit just finish all the protection latency issues; The 3rd, the delay circuit action delay circuit that comes into force, this circuit guarantee that the power supply rear delay circuit that really shut down just moves; The 4th, relatively confirm to carry out shutdown circuit, come into force behind the circuit by the delay circuit action delay, circuit operation is carried out in shutdown, the power supply shutdown; The 5th, turning-off delay circuit, during this circuit was carried out, no matter whether the external circuit operating state satisfied compressor start up condition, all is in off-mode, in order to avoid instantaneous start or repeated switching occur, reached the regular effect of having the hiccups and protecting time-delay of protection.
Embodiment one
As shown in Figure 2, behind the power work, DRA energy (DRA takes from the drive output signal of power supply PWM or takes from Transformer Winding etc.) is stored in the capacitor C 17 by diode D22, resistance R 24, and capacitor C 17 voltages reach DRA voltage and finish energy storage.Behind the power work, so that the G of triode Q14 is very low, be failure to actuate by protection by resistance R 88, triode Q15, resistance R 58 for DRA.After the DRA no-output, triode Q15 is not open-minded, and the energy on the capacitor C 17 gives capacitor C 24 chargings by resistance R 39, until capacitor C 24 voltages reach the Gth voltage of triode Q14, the time-delay circuit that comes into force is finished.After capacitor C 24 voltages reached the Gth voltage of triode Q14, triode Q14 was open-minded, and the OFF signal is carried out start.After the power supply shutdown, the energy of capacitor C 17 is by resistance R 51 discharges, and the RC constant that two elements forms and the Gth of DRA voltage and triode Q14 determine delay time.
Embodiment two
As shown in Figure 3, wherein the power work state detection circuit in above-described embodiment one replaces with the mos pipe.
Embodiment three
As shown in Figure 4, under the basis of embodiment two, will relatively confirm to carry out shutdown circuit and replace with comparator.
Above content is the further description of the invention being done in conjunction with concrete preferred implementation, can not assert that the implementation of this invention is confined to these explanations.For the invention person of an ordinary skill in the technical field, under the prerequisite that does not break away from the invention design, can also make some simple deduction or replace, all should be considered as belonging to the protection range of the invention.