CN218549737U - Control circuit for accelerating discharge of capacitor on input power supply - Google Patents

Abstract

The utility model relates to a control circuit for accelerating capacitor discharge on an input power supply, which comprises a fuse F1 connected with the anode of an external DC power supply, the other end connected with a piezoresistor RT1 and a TVS tube TVS1, the piezoresistor RT1 and the TVS tube TVS1 are both connected with the cathode of the external DC power supply, and the cathode of the external DC power supply is grounded; a power supply detection circuit is also connected between the fuse F1 and the negative electrode of the external direct current power supply; common mode inductance L1 connects load and ground connection, and common mode inductance L1 connects power inductance L2, connects the load through power inductance L2, is equipped with a plurality of filter capacitance between common mode inductance L1's the third end and the fourth end connection load's circuit, and common mode inductance L1 ground connection and connection diode D1 respectively also are equipped with a plurality of filter capacitance between common mode inductance L1's the second end and the first end. The capacitor accelerated discharge method and the capacitor accelerated discharge device can solve the problems of accelerated discharge of the capacitor after the system is powered off.

Description

Control circuit for accelerating discharge of capacitor on input power supply

Technical Field

The utility model relates to the technical field of circuits, concretely relates to a control circuit that is used for input power supply to go up electric capacity discharge with higher speed.

Background

In the field of industrial control, capacitors with different sizes are arranged on a control circuit and used for power filtering, particularly, in a circuit with high power ripple requirements, the capacitance added on a power line is large, but the large capacitance can enable the control system to continue working by the electricity stored on the capacitor after the system is introduced into power failure, so that when the power-down time is short, the power failure reset is insufficient, and the system is powered on abnormally.

Therefore, the prior art is generally realized by using a power-down detection circuit, when power-down is detected, a system power supply is cut off, and the method needs the IO pin of a CPU for control and needs software for matching realization; or the method is realized by adding the capacitor to a load, the discharge of the capacitor is accelerated by calculating a load resistor according to the capacitance, and the method also works all the time when the capacitor works, so that the energy is lost.

In summary, a control circuit for accelerating the discharge of a capacitor on an input power supply is needed to solve the above-mentioned problems.

SUMMERY OF THE UTILITY MODEL

The utility model aims at the above-mentioned problem that exists among the prior art, provide a control circuit that is used for input power supply to go up with higher speed electric capacity and discharges.

In order to realize the purpose of the utility model, the utility model adopts the following technical scheme: a fuse F1, a diode D1, a common mode inductor L1 and a power inductor L2 are sequentially connected with a control circuit for accelerating the discharge of a capacitor on an input power supply;

one end of the fuse F1, which is far away from the diode D1, is connected with the anode of an external direct-current power supply, the other end of the fuse F1 is also connected with the first end of the piezoresistor RT1 and the first end of the TVS tube TVS1, the second end of the piezoresistor RT1 and the second end of the TVS tube TVS1 are both connected with the cathode of the external direct-current power supply, and the cathode of the external direct-current power supply is grounded;

a power supply detection circuit is connected between the fuse F1 and the negative electrode of the external direct-current power supply, the power supply detection circuit detects power failure through a photoelectric coupler U1, and the power supply detection circuit further comprises a discharge loop so as to realize rapid discharge of residual electric quantity of the capacitor;

the load is connected and ground connection to common mode inductance L1's third end, and common mode inductance L1's fourth end connection power inductance L2's first end, connect the load through power inductance L2, be equipped with a plurality of filter capacitance between common mode inductance L1's third end and common mode inductance L1's the fourth end connection load's the circuit, common mode inductance L1's second end ground connection respectively and connect diode D1's first end, also be equipped with a plurality of filter capacitance between common mode inductance L1's second end and the common mode inductance L1's the first end.

The working principle and the beneficial effects are as follows: 1. compared with the prior art, the external direct-current power supply is output to a load through the fuse F1, the diode D1, the common-mode inductor L1 and the power inductor L2, the piezoresistor RT1 and the TVS tube TVS1 mainly play a role in overvoltage protection, a plurality of filter capacitors can play a good role in filtering, the power supply detection circuit detects power failure through the photoelectric coupler U1, rapid discharging of residual electric quantity of the capacitors is realized through the discharging loop, the power supply power failure can be detected under the condition that functions such as system EMC (electro magnetic compatibility) and the like are not influenced, the effect of accelerating discharging after power failure is realized, the power supply and power failure of the system are more reliable, the whole circuit is simple, and the realization difficulty is low;

2. compared with the prior art, the method does not adopt the existing mode of calculating the load resistance according to the capacitance, so that the load resistance always works when the work is not caused, and energy white loss is not caused.

Further, a capacitor C1 and a capacitor C2 are respectively connected between the first end of the common mode inductor L1 and the second end of the common mode inductor L1.

Further, a capacitor C3 and a capacitor C4 are connected between the third end of the common mode inductor L1 and the fourth end of the common mode inductor L1, and a capacitor C5 and a capacitor C6 are connected between the second end of the power inductor L2 and the third end of the common mode inductor L1.

Furthermore, one end of the capacitor C6, which is connected to the second end of the power inductor L2, is also connected to a power supply VCC _ PWR.

Furthermore, the capacitor C1, the capacitor C2, the capacitor C3, the capacitor C4, the capacitor C5, and the capacitor C6 form a filter circuit. Can play a good role in filtering.

Further, the capacitor C2, the capacitor C3, the capacitor C4, the capacitor C5, and the capacitor C6 are all ceramic capacitors.

Further, the capacitor C1 and the capacitor C5 are electrolytic capacitors.

Further, the power detection circuit comprises a resistor R1, a photoelectric coupler U1 and a PNP triode Q1, the second end of the diode D1 is connected to the first end of the resistor R1, the second end of the resistor R1 is connected to the first end of the photoelectric coupler U1, the first end of the capacitor C7 and the first end of the diode D2, the second end of the capacitor C7 and the second end of the diode D2 are connected to the negative electrode of the external direct current power supply and the second end of the photoelectric coupler U1, the second end of the photoelectric coupler U1 is connected to the negative electrode of the external direct current power supply, the third end of the photoelectric coupler U1 is connected to the first end of the zener diode D3 and the first end of the PNP triode Q1, the second end of the zener diode D3 and the third end of the PNP triode Q1 are grounded and connected to the second end of the resistor R4, the first end of the resistor R4 is connected to the first end of the zener diode D3 and the first end of the PNP triode Q1, the first end of the PNP triode U1 is connected to the first end of the resistor R2, the second end of the resistor R2 and the second end of the PNP triode Q3 are grounded and the second end of the resistor R3 are connected to the second end of the resistor R3, and the second end of the PNP triode Q1 are connected to the second end of the resistor R3, respectively, and the second end of the resistor R1 are connected to the PNP triode Q1.

Further, the diode D1 and the diode D2 are schottky diodes.

Further, the fuse F1 is a self-recovery fuse.

Drawings

Fig. 1 is a schematic diagram of the circuit structure of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art all belong to the protection scope of the present invention.

It will be understood by those skilled in the art that in the present disclosure, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship indicated in the drawings for ease of description and simplicity of description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be considered limiting.

As shown in fig. 1, the control circuit for accelerating the discharge of the capacitor on the input power supply includes a self-recovery fuse F1, a diode D1, a common mode inductor L1, and a power inductor L2, which are connected in sequence;

one end of the self-recovery fuse F1, which is far away from the diode D1, is connected with an anode DC + of an external direct-current power supply, the other end of the self-recovery fuse F1 is also connected with a first end of a piezoresistor RT1 and a first end of a TVS (transient voltage suppressor) 1, a second end of the piezoresistor RT1 and a second end of the TVS1 are both connected with a cathode DC-of the external direct-current power supply, and the cathode of the external direct-current power supply is grounded (GND _ PWR _ IN);

the self-recovery fuse F1 and the negative pole DC-of an external direct current power supply are connected with a power supply detection circuit, the power supply detection circuit detects power failure through a photoelectric coupler U1, and the power supply detection circuit further comprises a discharging loop to realize rapid discharging of residual electric quantity of a capacitor.

In this embodiment, the power detection circuit includes resistance R1, photoelectric coupler U1 and PNP triode Q1, diode D1's second end connecting resistance R1's first end, this resistance R1's second end is connected with photoelectric coupler U1's first end respectively, electric capacity C7's first end and diode D2's first end, electric capacity C7's second end and diode D2's second end all connect outside direct current power supply negative pole DC-and photoelectric coupler U1's second end, photoelectric coupler U1's second end connects outside direct current power supply negative pole DC-, and photoelectric coupler U1's third end is connected with zener diode D3's first end and PNP triode Q1's first end (base) respectively, zener diode D3's second end and PNP triode Q1's third end (collecting electrode) all divide ground connection and connecting resistance R4's second end respectively, this resistance R4's first end connects zener diode D3's first end and PNP triode Q1's first end respectively, photoelectric coupler U1's first end and PNP triode Q1's first end (collecting electrode) are connected with the first end of resistor R2, the first end of resistor R3 and the fourth end of PNP triode Q3's emitter (emitter connection respectively, resistor R3's first end and second end connect.

The third end of the common mode inductor L1 is connected with a load and is Grounded (GND), the fourth end of the common mode inductor L1 is connected with the first end of the power inductor L2, the load is connected through the power inductor L2, a capacitor C3 and a capacitor C4 are connected between the third end of the common mode inductor L1 and the fourth end of the common mode inductor L1 respectively, a capacitor C5 and a capacitor C6 are connected between the second end of the power inductor L2 and the third end of the common mode inductor L1 respectively, one end of the capacitor C6 connected with the second end of the power inductor L2 is also connected with a power supply VCC _ PWR, the second end of the common mode inductor L1 is grounded (GND _ PWR _ IN) and connected with the first end of the diode D1 respectively, and a capacitor C1 and a capacitor C2 are connected between the first end of the common mode inductor L1 and the second end of the common mode inductor L1 respectively.

In the present embodiment, the capacitor C1, the capacitor C2, the capacitor C3, the capacitor C4, the capacitor C5 and the capacitor C6 form a filter circuit. Can play a good role in filtering.

Preferably, the capacitor C2, the capacitor C3, the capacitor C4, the capacitor C5 and the capacitor C6 are all ceramic capacitors, and the capacitor C1 and the capacitor C5 are large-capacity electrolytic capacitors.

Preferably, the diode D1 and the diode D2 are schottky diodes.

Thus, an external direct current power supply (DC +, DC-) is output to a load through a self-recovery fuse F1, a diode D1, a common mode inductor L1 and a power inductor L2, a voltage dependent resistor RT1 and a TVS tube TVS1 mainly play a role of overvoltage protection, a filter circuit is composed of a capacitor C1, a capacitor C2, a capacitor C3, a capacitor C4, a capacitor C5 and a capacitor C6, in order to achieve a good filter effect, the capacities of the electrolytic capacitors C1 and C5 are both large and multiple, so that residual electric quantity still exists at two ends of the capacitor after the power supply is powered off, the load cannot be powered off in time, a power supply detection circuit is composed of the resistor R1, the resistor R2, the capacitor C7, the diode D2, a photoelectric coupler U1 and a voltage stabilizing tube D3, the capacitor C7 mainly plays a filtering role, the diode D2 mainly prevents the photoelectric coupler U1 from being burnt out by reverse connection of the power supply, PNP triode Q1 and resistor R2, resistor R4 forms the switching discharge circuit, when the positive pole DC + of external direct current power has electricity, through resistor R1, photoelectric coupler U1 input 1 foot (first end) is got electric, make photoelectric coupler U1 work, power VCC _ PWR is through resistor R2, photoelectric coupler U1 output end (third end and fourth end), stabilivolt D3 and resistor R4 form the return circuit, make photoelectric coupler U1 output 3 feet keep the high level, PNP triode Q1 handles and ends work, when power DC + cuts off the power, photoelectric coupler U1 inputs 1 foot (first end) low level, photoelectric coupler U1 does not work, PNP triode Q1 handles the conducting state, all electric capacity residual electric quantity forms the discharge return circuit through resistor R1, PNP triode Q1, resistor R4 and discharges rapidly, until the residual electric quantity finishes the work of discharge circuit.

Because the photoelectric coupler U1 is adopted for detection, the front ground plane and the rear ground plane of the common mode inductor L1 are not influenced mutually, the common mode inductor L1 still has an inhibition effect on EMC, the optical coupler transmits light, the EMC transmits electric signals, the ground wires on two sides are separated through the optical coupler (GND _ PWR _ IN and GND IN the figure 1), the electric signals are required to pass through a common mode inductor L1 loop, and the inhibition effect of the common mode inductor L1 on the EMC is guaranteed.

When the current is available, the base electrodes of the PNP triode Q1 and the base electrode Q1 are high in level, the triodes are not conducted, and the resistor R3 does not have current flowing through, so that the electric energy is not consumed.

The part of the utility model which is not described in detail is the prior art, so the utility model does not detail the part.

It is understood that the terms "a" and "an" should be interpreted as meaning that a number of one element or element is one in one embodiment, while a number of other elements is one in another embodiment, and the terms "a" and "an" should not be interpreted as limiting the number.

Although the use of the term in the present text is used more often, the possibility of using other terms is not excluded. These terms are used merely to more conveniently describe and explain the nature of the present invention; they are to be construed in a manner that is inconsistent with the spirit of the invention.

The present invention is not limited to the above-mentioned best mode, and any person can obtain other products in various forms under the teaching of the present invention, but any change in shape or structure is made, and all the technical solutions that are the same as or similar to the present application fall within the protection scope of the present invention.

Claims (10)

1. A control circuit for accelerating the discharge of a capacitor on an input power supply is characterized by comprising a fuse F1, a diode D1, a common mode inductor L1 and a power inductor L2 which are connected in sequence;

one end, far away from the diode D1, of the fuse F1 is connected with the anode of an external direct-current power supply, the other end of the fuse F1 is also connected with the first end of a piezoresistor RT1 and the first end of a TVS tube TVS1, the second end of the piezoresistor RT1 and the second end of the TVS tube TVS1 are both connected with the cathode of the external direct-current power supply, and the cathode of the external direct-current power supply is grounded;

a power supply detection circuit is connected between the fuse F1 and the negative electrode of the external direct-current power supply, the power supply detection circuit detects power failure through a photoelectric coupler U1, and the power supply detection circuit further comprises a discharge loop so as to realize rapid discharge of residual electric quantity of a capacitor;

the third end of common mode inductance L1 connects load and ground connection, just common mode inductance L1's fourth end is connected power inductance L2's first end, through power inductance L2 connects the load, common mode inductance L1's third end with be equipped with a plurality of filter capacitance between the circuit of common mode inductance L1's fourth end connection load, common mode inductance L1's second end ground connection respectively and connect diode D1's first end, common mode inductance L1's second end with also be equipped with a plurality of filter capacitance between common mode inductance L1's the first end.

2. The control circuit of claim 1, wherein a capacitor C1 and a capacitor C2 are respectively connected between the first end of the common mode inductor L1 and the second end of the common mode inductor L1.

3. The control circuit of claim 2, wherein a capacitor C3 and a capacitor C4 are connected between the third terminal of the common-mode inductor L1 and the fourth terminal of the common-mode inductor L1, respectively, and a capacitor C5 and a capacitor C6 are connected between the second terminal of the power inductor L2 and the third terminal of the common-mode inductor L1, respectively.

4. The control circuit of claim 3, wherein the end of the capacitor C6 connected to the second end of the power inductor L2 is further connected to a power supply VCC _ PWR.

5. The control circuit of claim 4, wherein the capacitor C1, the capacitor C2, the capacitor C3, the capacitor C4, the capacitor C5 and the capacitor C6 form a filter circuit.

6. The control circuit of claim 4, wherein said capacitor C2, said capacitor C3, said capacitor C4, said capacitor C5, and said capacitor C6 are all ceramic capacitors.

7. The control circuit of claim 4, wherein the capacitor C1 and the capacitor C5 are electrolytic capacitors.

8. The control circuit according to any one of claims 1 to 7, wherein the power detection circuit comprises a resistor R1, a photo-coupler U1 and a PNP transistor Q1, the second terminal of the diode D1 is connected to the first terminal of the resistor R1, the second terminal of the resistor R1 is connected to the first terminal of the photo-coupler U1, the first terminal of the capacitor C7 and the first terminal of the diode D2, the second terminal of the capacitor C7 and the second terminal of the diode D2 are connected to the negative terminal of the external dc power supply and the second terminal of the photo-coupler U1, the second terminal of the photo-coupler U1 is connected to the negative terminal of the external dc power supply, the third terminal of the photo-coupler U1 is connected to the first terminal of a zener diode D3 and the first terminal of the PNP transistor Q1, the second terminal of the zener diode D3 and the first terminal of the PNP transistor Q1 are connected to ground and the second terminal of the resistor R4, the first terminal of the resistor R4 is connected to the first terminal of the zener diode D3 and the first terminal of the PNP transistor Q1, and the fourth terminal of the resistor R3 are connected to ground, the first terminal of the PNP transistor Q2 and the first terminal of the resistor R3 are connected to ground, respectively.

9. The control circuit of claim 8, wherein the diode D1 and the diode D2 are schottky diodes.

10. The control circuit for accelerating the discharge of a capacitor on an input power supply of any one of claims 1 to 7, wherein said fuse F1 is a self-healing fuse.

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