CN101814823B - Low power consumption circuit using circuit starting resistor as bleeder resistor - Google Patents

Abstract

The invention discloses a low power consumption circuit using a circuit starting resistor as a bleeder resistor. The low power consumption circuit is connected into a power supply main circuit; the power supply main circuit comprises a control chip, a starting resistor connected with the control chip, and an X capacitor arranged at the front end of the power supply main circuit, wherein the low power consumption circuit comprises a voltage detection circuit connected into the power supply main circuit, a reference voltage circuit, a voltage comparison circuit, and an execution circuit for converting the starting resistor into the bleeder resistor of the X capacitor to perform voltage bleeding. The voltage at the X capacitor end is detected by using the voltage detection circuit, the detected voltage is compared with the voltage of the reference voltage circuit by using the voltage comparison circuit, and an electronic product of the execution circuit is controlled by the comparison result to convert the starting resistor connected with the control chip into the bleeder resistor of the X capacitor to perform voltage bleeding during normal power on and off. The low power consumption circuit has low power loss, and enables the X capacitor in the circuit to discharge as required after the power supply is pulled out.

Description

A kind of low consumption circuit that utilizes circuit starting resistor as bleeder resistance

Technical field the present invention relates to a kind of power circuit, relates in particular to a kind of low consumption circuit that utilizes circuit starting resistor as bleeder resistance.

X electric capacity in the various consumer electronics product power circuits of background technology is to be parallel to power input in order to filtering L, the filter capacitor of the difference mode signal between the N line.For the sake of security; The safety of various consumer electronics products requires product voltage on the X electric capacity after pulling out power line to release; Its way generally is the L at power input, parallelly connected more a string bleeder resistance between the N line, and the product of the resistance of this bleeder resistance and X electric capacity is generally less than 1 second; Select 0.47uF like X electric capacity, then the bleeder resistance maximum of corresponding parallel connection reaches 2M ohm.

Above-mentioned this bleeder resistance with the parallel connection of X electric capacity that appends can satisfy the requirement that the safety standard is released to the voltage on the X electric capacity; But will increase the power loss of electronic product simultaneously; Particularly under the electronic product holding state, it is bigger than normal that its power loss accounts for the ratio of total stand-by power consumption, for example: when input ac voltage is 240V; Stand-by power consumption under holding state is about the electronic product of 0.1W; The power consumption of the bleeder resistance that it is parallelly connected with X electric capacity is about 0.0288W, and its ratio that accounts for total stand-by power consumption reaches 28.8%, wastes many energy.And effort is all being done for improving the efficiency utilization in countries in the world at present; The energy-conservation mechanism of various countries has formulated start power consumption and the stand-by power consumption of more and more stricter efficiency standard with strictness control electronic product; Therefore; In order to reduce the electronic product power loss, must reduce or cancel the power loss that causes because of X electric capacity bleeder resistance.

Summary of the invention the object of the invention provide a kind of starting resistance that utilizes the Switching Power Supply control chip as X electric capacity bleeder resistance, can effectively reduce the low consumption circuit of electronic product power consumption.

The present invention adopts following scheme to realize: low consumption circuit of the present invention is connected in the electric power main circuit; Said electric power main circuit comprises control chip, the starting resistance that links to each other with control chip, is located at the X electric capacity of electric power main circuit front end; Wherein low consumption circuit comprises voltage detecting circuit, reference voltage circuit, voltage comparator circuit, executive circuit; The X capacitance terminal that is connected in said voltage detecting circuit detects X electric capacity voltage; Said reference voltage circuit is connected in the electric power main circuit and for voltage comparator circuit reference voltage is provided; Said voltage comparator circuit links to each other with voltage detecting circuit and reference voltage circuit respectively and carries out voltage ratio; Said executive circuit links to each other with electric power main circuit and voltage comparator circuit respectively, and said executive circuit converts said starting resistance into X electric capacity when electric power main circuit access failure power supply bleeder resistance carries out voltage and releases.

Said voltage detecting circuit comprises coupling capacitance, current-limiting resistance, the half-wave rectifying circuit that electrically connects successively; Said half-wave rectifying circuit comprises diode, voltage stabilizing didoe, detection sampling capacitor, and said detection sampling capacitor two ends also are parallel with the sampling capacitor bleeder resistance.

Said reference voltage circuit comprises voltage stabilizing didoe and the voltage regulation resistance that links to each other with this voltage stabilizing didoe negative pole, and said voltage regulation resistance links to each other with the energization pins of said control chip again.

Said voltage comparator circuit comprises a PNP triode; The collector electrode resistance grounded of said PNP triode; The emitter of said PNP triode connects the positive pole of the voltage stabilizing didoe in the said reference voltage circuit, and the base stage of said PNP triode links to each other with said half-wave rectifying circuit output again.

Said executive circuit comprises the diode that negative pole links to each other with starting resistance one end; This diode cathode is connected to the X capacitance terminal; The said starting resistance other end links to each other with the collector electrode of a NPN triode; The base stage of said NPN triode links to each other through the collector electrode of the said PNP triode in base resistance and the said voltage comparator circuit, and the emitter of said NPN triode is ground connection again.

The starting resistance that utilization of the present invention links to each other with control chip is as X electric capacity bleeder resistance; Utilize voltage detecting circuit to detect X capacitance terminal voltage; The voltage that detected voltage is outputed to voltage comparator circuit and reference voltage circuit and provides compares, and the starting resistance that is linked to each other by comparative result control executive circuit utilization and control chip again carries out the normal boot-strap operation and when electric power main circuit is not connected power supply, X electric capacity carried out voltage and release when start.

The invention has the beneficial effects as follows: the starting resistance that utilization of the present invention links to each other with control chip is as X electric capacity bleeder resistance; Both guaranteed that electronic product can meet the requirement that the safety standard is discharged to the X electric capacity in the circuit during electric power main circuit access failure power supply after pulling out power line; Again because of not increasing extra bleeder resistance at X electric capacity two ends; The power loss of entire circuit is low, and the present invention can energy savings, is fit to promote the use of.

Description of drawings combines accompanying drawing that the present invention is done further elaboration at present:

Fig. 1 is circuit theory diagrams of the present invention.

Embodiment is as shown in Figure 1; The present invention is connected in the electric power main circuit 1; The starting resistance 13 that electric power main circuit 1 comprises control chip 11, is located at the X electric capacity 12 of electric power main circuit 1 front end, links to each other with control chip 11; Low consumption circuit comprises voltage detecting circuit 2, reference voltage circuit 3, voltage comparator circuit 4, executive circuit 5; Said voltage detecting circuit 2 is connected in X electric capacity 12 ends and detects X electric capacity 12 voltage; Said reference voltage circuit 3 is connected in the electric power main circuit 1 and for voltage comparator circuit 4 reference voltage is provided; Said voltage comparator circuit 4 links to each other with voltage detecting circuit 2 and reference voltage circuit 3 respectively and carries out voltage ratio, and said executive circuit 5 links to each other with electric power main circuit 1 and voltage comparator circuit 4 respectively, and said executive circuit 5 converts said starting resistance 13 into X electric capacity 12 when electric power main circuit 1 access failure power supply bleeder resistance carries out voltage and releases.

Said voltage detecting circuit 2 comprises coupling capacitance C957, current-limiting resistance R959, the half-wave rectifying circuit 21 that electrically connects successively; Said half-wave rectifying circuit 21 comprises diode D945, voltage stabilizing didoe ZD943, detects sampling capacitor C958, and said detection sampling capacitor C958 two ends also are parallel with sampling capacitor bleeder resistance R960.

Said reference voltage circuit 3 comprises voltage stabilizing didoe ZD942 and the voltage regulation resistance R958 that links to each other with voltage stabilizing didoe ZD942 negative pole, and said voltage regulation resistance R958 links to each other with the energization pins of control chip 11 again; During the electronic product operate as normal, the voltage of half-wave rectifying circuit 21 outputs of voltage detecting circuit 2 output is higher than the reference voltage that reference voltage circuit 3 provides.

Said voltage comparator circuit 4 comprises a PNP triode Q942; The collector electrode of this PNP triode Q942 is through resistance R 961 ground connection; The emitter of this PNP triode Q942 connects the positive pole of the voltage stabilizing didoe ZD942 in the said reference voltage circuit 3, and the base stage of this PNP triode Q942 links to each other with said half-wave rectifying circuit 21 outputs again; During the electronic product operate as normal, the voltage of half-wave rectifying circuit 21 outputs of voltage detecting circuit 2 output is higher than the reference voltage that reference voltage circuit 3 provides, and this PNP triode Q942 ends.

Said executive circuit 5 comprises the diode D946 that negative pole links to each other with starting resistance 13 1 ends; Diode D946 positive pole is connected to X electric capacity 12 ends; Starting resistance 13 other ends link to each other with the collector electrode of a NPN triode Q943; The base stage of NPN triode Q943 links to each other through the collector electrode of the PNP triode Q942 in base resistance R962 and the said voltage comparator circuit 4, and the emitter of NPN triode Q943 is ground connection again.Starting resistance 13 comprises two continuous resistance R 948, R949, and X electric capacity 12 comprises capacitor C 917, C918.

When the electronic product normal boot-strap moves; Half-wave rectifying circuit 21 outputs of voltage detecting circuit 2 have voltage; And this moment is because the voltage that filter capacitor is still uncharged, reference voltage circuit 3 provides in the electric power main circuit 1 that control chip 11 power supply pin link is zero; PNP triode Q942 is ended; Thereby NPN triode Q943 is also ended, the alternating voltage of power input input through diode D946, starting resistance 13 be input to the high voltage startup pin of control chip 11 and give filter capacitor charging in the electric power main circuit 1 that is connected in control chip 11 power supply pin, up to accomplishing the starting up, electronic product begins normal operation.

When the electronic product operate as normal; Half-wave rectifying circuit 21 outputs of voltage detecting circuit 2 have voltage; But be higher than the reference voltage that reference voltage circuit 3 provides, thus PNP triode Q942 end, thereby NPN triode Q943 is also ended; When making electronic product keep the normal boot-strap operation, can not increase power loss.

After electronic product is pulling out power line; Voltage detecting circuit 2 does not have the alternating voltage input; Voltage on the detection sampling capacitor C958 in the voltage detecting circuit 2 is through the sampling capacitor bleeder resistance R960 decline of releasing, when the voltage on detecting sampling capacitor C958 is lower than the reference voltage that reference voltage circuit 3 provides, and PNP triode Q942 conducting; Thereby NPN triode Q943 conducting, the CE Exchange Settlement that the voltage on the X electric capacity 12 leads to diode D946, resistance R 948, R949, NPN triode Q943 bleeds off.

Claims (1)

1. low consumption circuit that utilizes circuit starting resistor as bleeder resistance; It is connected in the electric power main circuit; Said electric power main circuit comprises control chip, the starting resistance that links to each other with control chip, is located at the X electric capacity of electric power main circuit front end; It is characterized in that: low consumption circuit comprises voltage detecting circuit, reference voltage circuit, voltage comparator circuit, executive circuit; The X capacitance terminal that is connected in said voltage detecting circuit detects X electric capacity voltage; Said reference voltage circuit is connected in the electric power main circuit and for voltage comparator circuit reference voltage is provided; Said voltage comparator circuit links to each other with voltage detecting circuit and reference voltage circuit respectively and carries out voltage ratio, and said executive circuit links to each other with electric power main circuit and voltage comparator circuit respectively, and said executive circuit converts said starting resistance into the bleeder resistance of X electric capacity when electric power main circuit access failure power supply;

Said voltage detecting circuit comprises coupling capacitance, current-limiting resistance, the half-wave rectifying circuit that electrically connects successively; Said half-wave rectifying circuit comprises diode, voltage stabilizing didoe, detection sampling capacitor, and said detection sampling capacitor two ends also are parallel with the sampling capacitor bleeder resistance;

Said reference voltage circuit comprises voltage stabilizing didoe and the voltage regulation resistance that links to each other with this voltage stabilizing didoe negative pole, and said voltage regulation resistance links to each other with the energization pins of said control chip again;

Said voltage comparator circuit comprises a PNP triode; The collector electrode resistance grounded of said PNP triode; The emitter of said PNP triode connects the positive pole of the voltage stabilizing didoe in the said reference voltage circuit, and the base stage of said PNP triode links to each other with said half-wave rectifying circuit output again;

Said executive circuit comprises the diode that negative pole links to each other with starting resistance one end; This diode cathode is connected to the X capacitance terminal; The said starting resistance other end links to each other with the collector electrode of a NPN triode; The base stage of said NPN triode links to each other through the collector electrode of the said PNP triode in base resistance and the said voltage comparator circuit, and the emitter of said NPN triode is ground connection again.

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