CN2733709Y

CN2733709Y - Switching power supply apparatus

Info

Publication number: CN2733709Y
Application number: CN 200420033819
Authority: CN
Inventors: 彭军
Original assignee: Sichuan Changhong Electric Co Ltd
Current assignee: Sichuan Changhong Electric Co Ltd
Priority date: 2004-05-31
Filing date: 2004-05-31
Publication date: 2005-10-12
Anticipated expiration: 2014-05-31

Abstract

The utility model relates to a switching power supply apparatus which relates to the electronic technology, particularly switching power supply apparatuses. The utility model comprises a primary power supply circuit, a first power supply circuit, a second power supply circuit and a control circuit, wherein the primary power supply circuit provides the first power supply circuit and the second power supply circuit with the primary power supply voltage; the first power supply circuit provides a host machine with the service voltage; the second power supply circuit provides a readiness machine with the voltage; the control circuit controls the first power supply circuit according to commands; the second power supply circuit provides power supply support for the control circuit. The utility model has the advantages that the utility model can conveniently realize the power supply switching of the working state and the readiness state of the host machine, besides, the utility model has simple circuit, low cost and low readiness power consumption.

Description

Switching power unit

Technical field

The utility model relates to electronic technology, relates in particular to switching power unit.

Background technology

At present, DVD COMBO (as: DVD+RW, DVD+VCR+RW etc.) is becoming the main product in market, and it regularly records, puts and requirement such as demonstration arranged for when the standby CPU and the power supply of VFD display screen to the requirement of power supply to reach.Prior art adopts the required whole voltages of transformer output, turn-offs useless voltage with switch when standby, not only causes cost to increase, the secondary circuit complexity, and also stand-by power consumption is also than higher.

The utility model content

Technical problem to be solved in the utility model is, a kind of switching power unit is provided, and can realize that master/slave circuit supply switches.

The utility model solve the technical problem the technical scheme that is adopted, and a kind of switching power unit is provided, and comprising: the primary power circuit provides initial supply voltage to first power circuit and second source circuit; First power circuit provides host work voltage; The second source circuit provides standby voltage; Control circuit is according to commands for controlling first power circuit; Described second source circuit provides the power supply support for control circuit.

Described control circuit comprises a processor, and described processor is according to the operating state of commands for controlling first power circuit that receives.Described first power circuit comprises first transformer, and the elementary winding of described first transformer connects the primary power circuit, the secondary winding output voltage.Described control circuit also comprises first control chip, and described processor is controlled first power circuit by first control chip.Described control circuit comprises an optocoupler, the control termination processor of described optocoupler, and feedback winding one end of first transformer connects the input of optocoupler by diode, the other end ground connection of feedback winding, output termination first control chip of optocoupler.Also have a feedback circuit, described feedback circuit connects the output and first control chip of first power circuit.Described processor is a single-chip microcomputer.

The beneficial effects of the utility model are, can realize easily that the power supply between host work state and the holding state switches, and circuit are simple, and cost is low, and stand-by power consumption is low.

The utility model is described in further detail below in conjunction with the drawings and specific embodiments.

Description of drawings

Fig. 1 is a circuit block diagram of the present utility model.

Fig. 2 is the circuit diagram of the utility model embodiment.

Fig. 3 is the concrete circuit diagram of the utility model embodiment.

Embodiment

As shown in Figure 1, the utility model comprises primary power 3, first power circuit 1, second source circuit 2 and control circuit, primary power is connected with the second source circuit with first power circuit, the second source circuit is the control circuit power supply, control circuit is connected with first power circuit, controls the operating state of first power circuit.

Described first power circuit comprises first transformer, and first power circuit provides the working power of main frame, and the second source circuit is the control circuit power supply, and the power supply of holding state is provided.

As shown in Figure 2, connect an end of the elementary winding of first transformer in first power circuit 1 behind the power rectifier of input, the first Secondary winding of transformer output voltage, as the host work power supply, another termination control chip IC1 of elementary winding; Also have a buffer circuit in parallel with elementary winding, primary power is also received the elementary winding of second transformer of second source circuit, another termination control chip IC2 of the elementary winding of second transformer.

Control circuit comprises the feedback winding and the control chip IC1 of a single-chip microcomputer, optocoupler, first transformer, and single-chip microcomputer is controlled the operating state of first power circuit by optocoupler.One end ground connection of first power circuit feedback winding, the other end connects the input of optocoupler, the output termination control chip IC1 of optocoupler by diode.

SNUBBER CIRCUIT (buffer circuit), FEEDBACK CIRCUIT (feedback circuit) are all prior art among Fig. 2, and its concrete form is seen Fig. 3.

Fig. 3 has provided the concrete structure of circuit, exchanges input and connects A1, A3 2 points, and A1 is by the elementary winding contact A2 of transformer, and A3 is by Secondary winding of transformer contact A4, and A1 meets A3 by an electric capacity, and A2 is by electric capacity winding A4.The B1 point passes through capacity earth behind rectification circuit.Between B1 and the B2,, constitute buffer circuit by connecting with diode again after resistance and the electric capacity parallel connection.B1 also connects the B2 point through the elementary winding of first transformer.B2 process inductance connects the DRAIN pin of control chip IC1, and IC1 selects KA5Q0565 for use, and the DRAIN pin passes through capacity earth, GND ground connection, FB is by capacity earth, and SVNC passes through grounding through resistance, the feedback winding one end ground connection of first transformer, another termination C3 point, C3 connects the SVNC pin by two diodes.An output of first transformer connects the FB pin of control chip IC1 by an optocoupler.Second transformer is output as the stand-by circuit power supply that has single-chip microcomputer, and single-chip microcomputer connects the C2 point by an optocoupler, and the C2 point connects the base stage of triode Q5, the collector electrode of Q5 connects the base stage of Q6, C3 connects the C4 point by a diode, and C4 is by capacity earth, and C4 also resistance connects the base stage of Q6.C4 also connects the collector electrode of Q6, and the emitter of Q6 connects the C1 point, and C1 connects the VCC pin of control chip IC1, and VCC passes through capacity earth.C1 also connects the B1 point by resistance.

The output of second transformer is received the circuit board of being with CPU (perhaps single-chip microcomputer) by plug T1, is the CPU power supply, and the output of CPU is promptly controlled the output signal of power supply and also received control chip IC1 by plug T1.Specifically, connect the C2 point by optocoupler K1.

In the utility model, the concrete connected mode between CPU that relates to or single-chip microcomputer and the control chip belongs to current techique, does not repeat them here.

When complete machine is in holding state, the first transformer no-output that provides power supply to support for main frame, so main frame do not work, the stand-by circuit that has processor is in running order.When processor sent enabled instruction, by optocoupler control control chip IC1, control chip IC1 controlled the first power circuit work, and output voltage is supported main frame, and main frame is started working, and has realized the different power supplies of holding state and operating state.

Claims

1, switching power unit is characterized in that, comprising:

The primary power circuit provides initial supply voltage to first power circuit and second source circuit;

First power circuit provides host work voltage;

The second source circuit provides standby voltage;

Control circuit is according to commands for controlling first power circuit;

Described second source circuit provides the power supply support for control circuit.

2, switching power unit as claimed in claim 1 is characterized in that, described control circuit comprises a processor, and described processor is according to the operating state of commands for controlling first power circuit that receives.

3, switching power unit as claimed in claim 2 is characterized in that, described first power circuit comprises first transformer, and the elementary winding of described first transformer connects the primary power circuit, the secondary winding output voltage.

4, switching power unit as claimed in claim 3 is characterized in that, described control circuit also comprises first control chip, and described processor is controlled first power circuit by first control chip.

5, switching power unit as claimed in claim 4, it is characterized in that, described control circuit comprises an optocoupler, the control termination processor of described optocoupler, feedback winding one end of first transformer connects the input of optocoupler by diode, the other end ground connection of feedback winding, output termination first control chip of optocoupler.

6, switching power unit as claimed in claim 4 is characterized in that, also has a feedback circuit, and described feedback circuit connects the output and first control chip of first power circuit.

As claim 2,3,4,5 or 6 described switching power units, it is characterized in that 7, described processor is a single-chip microcomputer.