CN201504186U - Switch power supply low standby loss control circuit capable of automatically detecting load - Google Patents
Switch power supply low standby loss control circuit capable of automatically detecting load Download PDFInfo
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- CN201504186U CN201504186U CN2009202193997U CN200920219399U CN201504186U CN 201504186 U CN201504186 U CN 201504186U CN 2009202193997 U CN2009202193997 U CN 2009202193997U CN 200920219399 U CN200920219399 U CN 200920219399U CN 201504186 U CN201504186 U CN 201504186U
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- power supply
- switching power
- main switch
- resistance
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Abstract
The utility model discloses a switch power supply low standby loss control circuit capable of automatically detecting load, which comprises a main switch tube Sm, a driving circuit thereof, a circuit for automatically detecting the load state and a power supplying circuit, wherein the main switch tube Sm and the driving circuit thereof are connected to a switch power supply in series. The main switch tube Sm is used for controlling the whole switch power supply to be on or off. The main switch tube Sm is controlled to switch on or off according to the results that load states are automatically detected. When the switch power supply is not connected to a load, the main switch tube Sm is switched off, the power supplying of the switch power supply is cut off, the output voltage is zero, and the part zero stand-by loss of the switch power supply is realized. After the load is connected, the main switch tube Sm is switched on, and the switch power supply is on normally. The switch power supply low standby loss control circuit does not need a special control iron sheet, has the advantages of simple design, low cost, small self loss and high reliability, and is suitable for various switch power supplies.
Description
Technical field
The utility model relates to electric and electronic technical field, is specifically related to a kind of low standby loss control circuit of switching power supply that can detect load condition automatically.
Background technology
Along with various electric appliance and electronic products popularizing in work and life, the application scenario of Switching Power Supply is very extensive.Because increasing product has had idle function (as remote control switch, WOL, timing switch, intelligent switch etc.), the idling consumption of Switching Power Supply becomes a very important waste.According to statistics, idling consumption has accounted for 3%～13% of residential electricity consumption.Along with the global energy growing tension, various countries have formulated relevant policy and measure one after another and have limited and reduce standby energy consumption, as " 1W plan ", " Energy Star " of the U.S. of International Energy Agency (IEA), the blue angels in Europe etc.Require rated power to be no more than 0.3W less than the power supply standby power of 50W at present, rated power is no more than 0.5W greater than 50W and less than the power supply idling consumption of 250W, and As time goes on, will be more and more stricter to the requirement of idling consumption.
The method that is used to reduce the Switching Power Supply idling consumption at present mainly is divided into two kinds: first kind is control Switching Power Supply operating frequency when unloaded, comprises the default formula control of pulse, batch (-type) control and turn-off time adjustable type control etc.By reducing switching frequency, effectively reduce switching loss and drive loss, thereby reduce idling consumption.But control circuit maintenance work requires the expenditure of energy during the standby, and switching loss and drive loss still exist, so be difficult to satisfy the idling consumption requirement of increasingly stringent.Second kind is to increase auxiliary converter, and the main power source converter is not worked during the standby, auxiliary converter work, and the size of idling consumption is determined by auxiliary converter fully.But cooperation between auxiliary converter and the main power source converter and switching need design special control strategy or switch controller, cause this method cost height, control complexity, do not have universality.
In view of the shortcoming of above-mentioned prior art, demand urgently needing a kind of technical scheme that is suitable for the reduction idling consumption of all kinds Switching Power Supply, can realize the target of Switching Power Supply zero idling consumption.
The utility model content
The purpose of this utility model is to overcome the prior art above shortcomings, and a kind of low standby loss control circuit of switching power supply that can detect load automatically is provided.The utility model is by detecting the state of load, and making the output voltage of Switching Power Supply when non-loaded is zero, realizes Switching Power Supply part zero idling consumption.And when load inserted, Switching Power Supply can normally start work.The utility model circuit oneself power consumption is little, and is very little to the operating efficiency influence of Switching Power Supply.Concrete technical scheme is as follows:
A kind of low standby loss control circuit of switching power supply that can detect load condition automatically comprises the automatic testing circuit of load condition, power supply circuits, main switch S
mWith main switch S
mDrive circuit, the main circuit of described Switching Power Supply comprises filter, rectifier bridge, input filter capacitor C
i, DC/DC converter, output capacitance C
oWith sampling resistor R
S, it is characterized in that described Switching Power Supply power supply is by main switch S
mControl, main switch S
mSource electrode and Switching Power Supply main circuit in the negative output terminal of rectifier bridge link to each other main switch S
mDrain electrode and the input filter capacitor C in the Switching Power Supply main circuit
iNegative terminal link to each other; As main switch S
mConducting, the Switching Power Supply normal power supply; Main switch S
mTurn-off the output of Switching Power Supply no-voltage.
Above-mentioned can detect in the low standby loss control circuit of switching power supply of load condition described main switch S automatically
mDrive circuit be by the first transformer T
1Secondary winding, the second transformer T
2First secondary winding W
1, the first switching tube S
1, second switch pipe S
2, the first rectifier bridge BD
1, the second rectifier bridge BD
2, first capacitor C
1, second capacitor C
2, first resistance R
1, second resistance R
2, the first voltage stabilizing didoe Z
1, the second voltage stabilizing didoe Z
2Constitute the first transformer T with optocoupler OC
1The secondary winding and the first rectifier bridge BD
1Input link to each other the first rectifier bridge BD
1Positive output end and main switch S
mGate pole, the first switching tube S
1Drain electrode, second switch pipe S
2Gate pole, the collector output of optocoupler OC, first resistance R
1An end, first capacitor C
1Anode and voltage stabilizing didoe Z
1Negative electrode link to each other; The first rectifier bridge BD
1Negative output terminal and main switch S
mSource electrode, the first switching tube S
1Source electrode, second switch pipe S
2Source electrode, the emitter output of optocoupler OC, first resistance R
1The other end, first capacitor C
1Negative terminal and voltage stabilizing didoe Z
1Anode link to each other; The second transformer T
2First secondary winding W
1With the second rectifier bridge BD
2Input link to each other the second rectifier bridge BD
2The positive output end and the first switching tube S
1Gate pole, second switch pipe S
2Drain electrode, second resistance R
2An end, second capacitor C
2Anode and voltage stabilizing didoe Z
2Negative electrode link to each other the second rectifier bridge BD
2The negative output terminal and the first rectifier bridge BD
1Negative output terminal, second resistance R
2The other end, second capacitor C
2Negative terminal, voltage stabilizing didoe Z
2Anode link to each other.
Above-mentioned can detect in the low standby loss control circuit of switching power supply of load condition automatically, after the non-loaded or original load of Switching Power Supply is cut, and the first switching tube S
1Conducting or optocoupler OC work, main switch S
mGate voltage is reduced to opens below the threshold voltage main switch S
mTurn-off the Switching Power Supply no-output; When Switching Power Supply has load, the first switching tube S
1Turn-off main switch S
mGate voltage raises, main switch S
mConducting.Second switch pipe S
2Conducting simultaneously makes the first switching tube S
1Gate voltage keep low level, when preventing the Switching Power Supply operate as normal because of the first switching tube S
1Open by mistake and lead to and cause the shutoff of Switching Power Supply mistake.
Above-mentioned can detect in the low standby loss control circuit of switching power supply of load condition automatically, and before described Switching Power Supply started, the load condition testing circuit was by the second transformer T
2Second secondary winding W
2, the 3rd rectifier bridge BD
3Constitute the second transformer T
2Second secondary winding W
2With the 3rd rectifier bridge BD
3Input link to each other the 3rd rectifier bridge BD
3Positive output end link to each other the 3rd rectifier bridge BD with the cathode output end of Switching Power Supply
3Negative output terminal link to each other with the cathode output end of Switching Power Supply.
Above-mentioned can detect in the low standby loss control circuit of switching power supply of load condition automatically, and the load condition testing circuit changed the second transformer T by detecting the situation of load impedance before Switching Power Supply started
2First secondary winding W
1The size of induced electromotive force; When non-loaded when linking to each other with Switching Power Supply, the second rectifier bridge BD
2The output high level, the first switching tube S
1Conducting makes main switch S
mTurn-off; When load links to each other with Switching Power Supply, the second rectifier bridge BD
2Output low level, the first switching tube S
1Turn-off, make main switch S
mConducting.
Above-mentioned can detect in the low standby loss control circuit of switching power supply of load condition automatically, and the load condition testing circuit after the normal startup of described switching tube power supply is by diode D, the first triode Q
1, the second triode Q
2, the 3rd triode Q
3, the 3rd resistance R
3, the 4th resistance R
4, the 5th resistance R
5, the 6th resistance R
6, the 7th resistance R
7Constitute with optocoupler OC; The anode input of optocoupler OC and the 3rd triode Q
3Collector electrode and resistance R
4An end link to each other negative electrode input and resistance R
3An end connect; Resistance R
3The other end and the 3rd triode Q
3Emitter, the second triode Q
2Emitter, the first triode Q
1Emitter and the Switching Power Supply main circuit in sampling resistor R
SLow level end link to each other; The 3rd triode Q
3The base stage and the second triode Q
2Collector electrode, resistance R
5An end connect; The second triode Q
2The base stage and the first triode Q
1Collector electrode, resistance R
6An end link to each other the first triode Q
1Base stage and anode, the resistance R of diode D
7An end connect; Resistance R
4The other end, resistance R
5The other end, resistance R
6The other end, resistance R
7The other end link to each other with the cathode output end of Switching Power Supply; The negative electrode of diode D and the cathode output end of Switching Power Supply, sampling resistor R
SThe high level end link to each other.
Above-mentioned can detect in the low standby loss control circuit of switching power supply of load condition automatically, the load condition testing circuit that described switching tube power supply is normal after starting when the Switching Power Supply band carries operate as normal, sampling resistor R
SOn pressure drop be high level, the first triode Q
1Conducting, the second triode Q
2Turn-off the 3rd triode Q
3Conducting, optocoupler OC ends, and output keeps high impedance, main switch S
mKeep conducting; If carve at a time and remove load, sampling resistor R
SOn pressure drop become low level, the first triode Q
1Turn-off diode Q
2Conducting, the 3rd triode Q
3Turn-off, optocoupler OC conducting, the output Low ESR is given main switch S
mGate voltage provides discharge loop; As main switch S
mGate voltage be reduced to its threshold voltage when following, main switch S
mTurn-off.
Above-mentioned can detect in the low standby loss control circuit of switching power supply of load condition automatically, and the power supply of described control circuit is by electrodeless electric capacity C
X1, C
X2With the first transformer T
1Former limit winding, the second transformer T
2Former limit winding dividing potential drop realize capacitor C
X1An end and the first transformer T
1The end of the same name of former limit winding links to each other, capacitor C
X1The other end with exchange input L bus and link to each other the first transformer T
1The different name end of former limit winding with exchange input N bus and link to each other; Capacitor C
X2An end and the second transformer T
2The end of the same name of former limit winding links to each other, capacitor C
X2The other end with exchange input N bus and link to each other the second transformer T
2The different name end of former limit winding with exchange input N bus and link to each other.
Compared with prior art, the utility model circuit does not need special control chip, and simplicity of design, cost is low, own loss is little, reliability is high, is applicable to various Switching Power Supplies.The 100W Switching Power Supply of the utility model circuit is adopted in checking by experiment, and its minimum idling consumption only be about 25mW, far below the idling consumption requirement of " Energy Star (V) " (≤0.5W).When the non-loaded connection of Switching Power Supply, the utility model circuit cuts off the power supply input of Switching Power Supply fully, and making switch power source output voltage is zero, and this moment, the idling consumption of Switching Power Supply only was the own loss of this utility model circuit; No matter when insert load, Switching Power Supply all can normally start work.
Description of drawings
Figure
1For detecting the structure chart of the low standby loss control circuit of switching power supply of load condition in the utility model embodiment automatically, the part among the figure outside the frame of broken lines is the Switching Power Supply main circuit.
Fig. 2 a～Fig. 2 d is that input ac voltage is V
In=
115V
ACThe time, the main waveform of test piece, wherein, when Fig. 2 a is starting under no load, main switch S
mGate voltage (Ch1), the first switching tube S
1Gate voltage (Ch3) and the waveform of switch power source output voltage (Ch4);
When Fig. 2 b is the bringing onto load startup, main switch S
mGate voltage (Ch 1), the gate voltage (Ch 3) of the first switching tube S1 and the waveform of switch power source output voltage (Ch 4);
Fig. 2 c be from zero load when inserting load variations, main switch S
mGate voltage (Ch 1), the first switching tube S
1Gate voltage (Ch 3) and the waveform of switch power source output voltage (Ch 4);
When Fig. 2 d changes for be downloaded to zero load from band, main switch S
mGate voltage (Ch 1), the first switching tube S
1Gate voltage (Ch 3) and the waveform of switch power source output voltage (Ch 4).
Fig. 3 a～Fig. 3 d is that input ac voltage is V
In=
230V
ACThe time, the main waveform of test piece, wherein, when Fig. 3 a is starting under no load, main switch S
mGate voltage (Ch 1), the first switching tube S
1Gate voltage (Ch 3) and the waveform of switch power source output voltage (Ch 4);
When Fig. 3 b is the bringing onto load startup, main switch S
mGate voltage (Ch 1), the first switching tube S
1Gate voltage (Ch 3) and the waveform of switch power source output voltage (Ch 4);
Fig. 3 c be from zero load when inserting load variations, main switch S
mGate voltage (Ch 1), the first switching tube S
1Gate voltage (Ch 3) and the waveform of switch power source output voltage (Ch 4);
When Fig. 3 d changes for be downloaded to zero load from band, main switch S
mGate voltage (Ch 1), the first switching tube S
1Gate voltage (Ch 3) and the waveform of switch power source output voltage (Ch 4).
Embodiment
Below in conjunction with accompanying drawing concrete enforcement of the present utility model is described further.
A kind of low standby loss control circuit of switching power supply that can detect load condition automatically in the present embodiment as shown in Figure 1, mainly comprises the main switch S that is serially connected in the Switching Power Supply main circuit
mAnd drive circuit, the automatic testing circuit of load condition and power supply circuits.
As Fig. 1, main switch S
mBe serially connected on the Switching Power Supply current supply circuit.Main switch S
mDuring conducting, the Switching Power Supply operate as normal; Main switch S
mDuring shutoff, the Switching Power Supply outage can not be worked, and output voltage is zero, and idling consumption also is zero.
Main switch S
mDrive circuit, be by the first transformer T
1Secondary winding, the second transformer T
2First secondary winding W
1, the first switching tube S
1, second switch pipe S
2, the first rectifier bridge BD
1, the second rectifier bridge BD
2, first capacitor C
1, second capacitor C
2, first resistance R
1, second resistance R
2, voltage stabilizing didoe Z
1, voltage stabilizing didoe Z
2Constitute with optocoupler OC.As the first switching tube S
1When conducting or optocoupler OC work, main switch S
mGate voltage drops to opens below the threshold voltage main switch S
mTurn-off; As the first switching tube S
1Turn-off main switch S
mGate voltage raises, and makes main switch S
mOpen-minded, second switch pipe S
2Open-minded simultaneously.Second switch pipe S
2After the conducting, the first switching tube S
1Turn-off, guarantee main switch S
mCan be because of the first switching tube S
1Mislead and the mistake shutoff.
Load condition testing circuit before Switching Power Supply starts is by the second transformer T
2Second secondary winding W
2, rectifier bridge BD
3Constitute.T-shape equivalent theory based on transformer, transformer secondary induced electromotive force can equivalence be the dividing potential drop of former limit input voltage on equiva lent impedance, therefore the change of transformer load impedance that secondary connects, the equiva lent impedance that can directly influence transformer changes, and also just has influence on the size of transformer secondary induced electromotive force.If the secondary winding of transformer connects load, because of load impedance much smaller than excitatory impedance, so the dividing potential drop on the load impedance is little, corresponding induced electromotive force is also little; If the secondary of transformer open circuit, situation is then opposite.Switching Power Supply starts preceding load condition testing circuit according to above-mentioned principle design in the utility model, the second transformer T
2First secondary winding W
1With second secondary winding W
2Turn ratio is fixed, therefore, and the second transformer T
2First secondary winding W
1Induced electromotive force can be with second secondary winding W
2Induced electromotive force change and change.When load connects, winding W
2Induced electromotive force diminish winding W then because of connecting load
1Also corresponding the diminishing of induced electromotive force, this induced electromotive force is through the second rectifier bridge BD
2After the rectification, if less than the first switching tube S
1Open threshold voltage, the then first switching tube S
1Not conducting; When non-loaded connection, winding W
2Induced electromotive force increase winding W
1The also corresponding increase of induced electromotive force, this induced electromotive force is through the second rectifier bridge BD
2After the rectification, if greater than the first switching tube S
1Open threshold voltage, the then first switching tube S
1Conducting.S
1After the conducting, make main switch S
mGate voltage reduce to low level, main switch S
mTurn-off, Switching Power Supply does not have power supply, realizes zero idling consumption.The Switching Power Supply of mentioning in the utility model starts the back loading testing circuit, is by diode D, the first triode Q
1, the second triode Q
2, the 3rd triode Q
3, resistance R
3, resistance R
4, resistance R
5, resistance R
6, resistance R
7Constitute with optocoupler OC.Described Switching Power Supply starts the back loading testing circuit after the normal startup of Switching Power Supply, by the sampling resistor R of sense switch power supply
SOn pressure drop judge that load connects situation.The sampled voltage signal is through diode D, the first triode Q
1, the second triode Q
2, the 3rd triode Q
3, resistance R
3, resistance R
4, resistance R
5, resistance R
6, resistance R
7The amplifying circuit of forming is used to control optocoupler OC after amplifying.When Switching Power Supply bringing onto load operate as normal, sampling resistor R
SOn pressure drop be high level, the first triode Q
1Conducting, the second triode Q
2Turn-off the 3rd triode Q
3Conducting, therefore, the 3rd triode Q
3Collector voltage be low level, can't drive optocoupler OC, the optocoupler output is a high impedance, main switch S
mKeep conducting; If carve the load of removing Switching Power Supply, sampling resistor R at a time
SOn pressure drop become low level, the first triode Q
1Turn-off diode Q
2Conducting, the 3rd triode Q
3Turn-off, therefore, the 3rd triode Q
3Collector voltage be high level, drive the light-emitting diode conducting of optocoupler OC, the optocoupler output is a Low ESR, is main switch S
mGate voltage discharge loop is provided, make its shutoff.
The power supply of the control circuit in the present embodiment derives from ac bus, capacitor C
X1, C
X2With the first transformer T
1, T
2Former limit windings in series, make the first transformer T
1, T
2Former limit obtain a lower dividing potential drop, guarantee that the own loss of utility model circuit is very little.
The enforcement of the circuit of present embodiment mainly is divided into five kinds of situations:
Situation one: when switch power supply no-load starts, rectifier bridge BD
3Output keep high impedance, the first rectifier bridge BD
1, the second rectifier bridge BD
2Output voltage all begin to rise.The first rectifier bridge BD
1, the second rectifier bridge BD
2The output voltage rise time is respectively by first capacitor C
1, first resistance R
1With second capacitor C
2, second resistance R
2Size decision.Adjust first resistance R
1, first capacitor C
1, second resistance R
2, second capacitor C
2Size, make the second rectifier bridge BD
2The rise of output voltage speed ratio first rectifier bridge BD
1Output voltage fast guaranteed the first rectifier bridge BD
1Output voltage rises to main switch S
mOpen before the threshold voltage value the second rectifier bridge BD
2Output voltage risen to the first switching tube S
1Open threshold voltage, S
1Conducting in advance makes main switch S
mGate voltage be low level, main switch S
mKeep turn-offing, the current supply circuit of Switching Power Supply is by main switch S at this moment
mCut off, output voltage is zero.Shown in Fig. 2 a, Fig. 3 a.
Situation two: when the Switching Power Supply bringing onto load starts, the second transformer T
2The first secondary winding W
1On the situation of induced electromotive force during also much smaller than zero load.This electromotive force is through the second rectifier bridge BD
2After the rectification, magnitude of voltage is lower than the first switching tube S
1Open threshold voltage, the first switching tube S
1Keep off state.The first rectifier bridge BD
1The output high level makes main switch S
mWith second switch pipe S
2Conducting simultaneously, second switch pipe S
2After the conducting, make the first switching tube S
1Gate voltage remain low level, S
1Turn-off.Shown in Fig. 2 b, Fig. 3 b.
Situation three: when switch power supply no-load starts back access load, because the second transformer T
2Equiva lent impedance reduce, make the second transformer T
2The first secondary winding W
1Induced electromotive force also reduce, correspondingly, the second rectifier bridge BD
2Output voltage drop to the first switching tube S
1Open below the threshold voltage the first switching tube S
1Turn-off.At this moment, the first rectifier bridge BD
1Output voltage rise main switch S
mWith second switch pipe S
2Conducting simultaneously.Second switch pipe S
2After the conducting, make the first switching tube S
1Gate voltage remain low level, when preventing the Switching Power Supply operate as normal because of the first switching tube S
1Open by mistake and lead to and cause the shutoff of Switching Power Supply mistake.Shown in Fig. 2 c, Fig. 3 c.
Situation four: when the Switching Power Supply band carried operate as normal, the testing circuit of load condition was by detecting sampling resistor R
SOn voltage swing judge loading condition.If the work of Switching Power Supply bringing onto load, sampling resistor R
SOn voltage reduce to high level, the 3rd triode Q
3Current collection low level very, be not enough to drive optocoupler OC, do not influence main switch S
mWork, Switching Power Supply keeps normal operating conditions; If carve at a time and remove load, the voltage drop of sampling resistor becomes low level, then the 3rd triode Q
3Current collection high level very, drive the light-emitting diode of optocoupler OC, the output of optocoupler OC becomes Low ESR, is main switch S
mGate voltage discharge loop is provided, the gate voltage of switching tube is reduced to rapidly opens below the threshold voltage main switch S
mTurn-off, the output voltage of Switching Power Supply is reduced to zero gradually, enters the low idling consumption pattern, as Fig. 2 d, Fig. 3 d.
Situation five: as described in situation four, the Switching Power Supply operate as normal is if at a time remove load, main switch S
mTurn-off, switch power source output voltage is by the electrochemical capacitor C of output
oProvide, and descend gradually.If in this process, insert load once more, this moment output capacitance C
oTo load discharge, output voltage can be reduced to zero moment, at this moment, and the second transformer T
2, rectifier bridge BD
3The load detecting circuit of forming is started working, and as described in situation two, the Switching Power Supply band carries startup.
In order to verify the function of the utility model circuit, test piece adopts a power supply adaptor (model is AD10048P3) of Yada Electronics Co., Ltd's manufacturing, and its major parameter is: input voltage V
In=100～240Vac, 50/60Hz; Specified direct current output 48V/2.08A.Before and after improving the idling consumption Pin (W) of each test (Test) of this sample and mean value Avg the results are shown in Table 1, table 2, contrast finds that behind employing the utility model circuit, the idling consumption of Switching Power Supply obviously reduces, minimum idling consumption is 25.36mW.Far below " Energy Star 2.0 " desired standard (≤0.5W).
Table 1
Table 2
It is V that Fig. 2 a～Fig. 2 d, Fig. 3 a～Fig. 3 d is respectively input ac voltage
In=
115VaC/
23During 0VaC, main switch S
mAnd S
1Gate voltage and the output voltage V of Switching Power Supply
OuT waveform: among each figure, be main switch S topmost
mGate voltage waveform (Ch
1), the centre is the first switching tube S
1Gate voltage waveform (Ch
3), the bottom is the waveform (Ch4) of output voltage.Wherein,
Fig. 2 a, the voltage waveform of each point when Fig. 3 a is the circuit No Load Start are at main switch S
mGate voltage reaches to be opened before the threshold voltage, the first switching tube S
1Gate voltage reached it and opened threshold voltage, the first switching tube S
1Open-minded, main switch S
mKeep turn-offing, switch power source output voltage is zero, corresponding foregoing situation one.
The voltage waveform of each point when Fig. 2 b, Fig. 3 b start for band carries, the first switching tube S
1Gate voltage be lower than and open threshold voltage, the first switching tube S
1Be in off state, main switch S
mGate voltage rise to gradually open threshold voltage after, main switch S
mConducting, second switch pipe S simultaneously
2Also conducting is the first switching tube S
1Gate voltage be limited in low level, Switching Power Supply output rated voltage, corresponding foregoing situation two.
Fig. 2 c, Fig. 3 c are the voltage waveform from No Load Start each point when inserting load variations, after Switching Power Supply inserts load, and the first switching tube S
1Gate voltage drop to zero, main switch S
mGate voltage rise gradually, drive main switch S
mOpen-minded, Switching Power Supply starts, output rated voltage, corresponding foregoing situation three.
To be Switching Power Supply carry the voltage waveform of work each point when zero load changes from band for Fig. 2 d, Fig. 3 d, after the load of Switching Power Supply is removed, and main switch S
mGate voltage quickly fall to zero, main switch S
mTurn-off, simultaneously the first switching tube S
1Gate voltage rise the first switching tube S rapidly
1Conducting.The output voltage of Switching Power Supply will drop to zero gradually.
Find out that from experimental result the utility model can effectively reduce the idling consumption of Switching Power Supply, do not influence the service behaviour of Switching Power Supply.
Claims (8)
1. the low standby loss control circuit of switching power supply that can detect load condition automatically comprises the automatic testing circuit of load condition, power supply circuits, main switch (S
m) and main switch (S
m) drive circuit, the main circuit of described Switching Power Supply comprises filter, rectifier bridge, input filter capacitor (C
i), DC/DC converter, output capacitance (C
o) and sampling resistor (R
S), it is characterized in that described Switching Power Supply power supply is by main switch (S
m) control, main switch (S
m) source electrode and Switching Power Supply main circuit in the negative output terminal of rectifier bridge link to each other main switch (S
m) drain electrode and the input filter capacitor (C in the Switching Power Supply main circuit
i) negative terminal link to each other; As main switch (S
m) conducting, the Switching Power Supply normal power supply; Main switch (S
m) turn-off the output of Switching Power Supply no-voltage.
2. a kind of low standby loss control circuit of switching power supply that can detect load condition automatically according to claim 1 is characterized in that described main switch (S
m) drive circuit be by the first transformer (T
1) secondary winding, the second transformer (T
2) first secondary winding (W
1), the first switching tube (S
1), second switch pipe (S
2), the first rectifier bridge (BD
1), the second rectifier bridge (BD
2), the first electric capacity (C
1), the second electric capacity (C
2), the first resistance (R
1), the second resistance (R
2), the first voltage stabilizing didoe (Z
1), the second voltage stabilizing didoe (Z
2) and optocoupler (OC) formation, the first transformer (T
1) the secondary winding and the first rectifier bridge (BD
1) input link to each other the first rectifier bridge (BD
1) positive output end and main switch (S
m) gate pole, the first switching tube (S
1) drain electrode, second switch pipe (S
2) gate pole, the collector output of optocoupler (OC), the first resistance (R
1) an end, the first electric capacity (C
1) anode and voltage stabilizing didoe (Z
1) negative electrode link to each other; First rectifier bridge (the BD
1) negative output terminal and main switch (S
m) source electrode, the first switching tube (S
1) source electrode, second switch pipe (S
2) source electrode, the emitter output of optocoupler (OC), the first resistance (R
1) the other end, the first electric capacity (C
1) negative terminal and voltage stabilizing didoe (Z
1) anode link to each other; Second transformer (the T
2) first secondary winding (W
1) and the second rectifier bridge (BD
2) input link to each other the second rectifier bridge (BD
2) the positive output end and the first switching tube (S
1) gate pole, second switch pipe (S
2) drain electrode, the second resistance (R
2) an end, the second electric capacity (C
2) anode and voltage stabilizing didoe (Z
2) negative electrode link to each other the second rectifier bridge (BD
2) the negative output terminal and the first rectifier bridge (BD
1) negative output terminal, the second resistance (R
2) the other end, the second electric capacity (C
2) negative terminal, voltage stabilizing didoe (Z
2) anode link to each other.
3. the low standby loss control circuit of switching power supply that can detect load condition automatically according to claim 2 is characterized in that after the non-loaded or original load of Switching Power Supply is cut the first switching tube (S
1) conducting or optocoupler (OC) work, main switch S
mGate voltage is reduced to opens below the threshold voltage main switch (S
m) turn-off the Switching Power Supply no-output; When Switching Power Supply has load, the first switching tube (S
1) turn-off main switch (S
m) the gate voltage rising, main switch (S
m) conducting; Second switch pipe (S
2) conducting simultaneously, make the first switching tube (S
1) gate voltage keep low level, when preventing the Switching Power Supply operate as normal because of the first switching tube (S
1) open by mistake logical and cause the Switching Power Supply mistake to be turn-offed.
4. a kind of low standby loss control circuit of switching power supply that can detect load condition automatically according to claim 1 is characterized in that, before described Switching Power Supply started, the load condition testing circuit was by the second transformer (T
2) second secondary winding (W
2), the 3rd rectifier bridge (BD
3) constitute the second transformer (T
2) second secondary winding (W
2) and the 3rd rectifier bridge (BD
3) input link to each other the 3rd rectifier bridge (BD
3) positive output end link to each other the 3rd rectifier bridge (BD with the cathode output end of Switching Power Supply
3) negative output terminal link to each other with the cathode output end of Switching Power Supply.
5. a kind of low standby loss control circuit of switching power supply that can detect load condition automatically according to claim 4 is characterized in that, the load condition testing circuit changed the second transformer (T by detecting the situation of load impedance before Switching Power Supply started
2) first secondary winding (W
1) the size of induced electromotive force; When non-loaded when linking to each other with Switching Power Supply, the second rectifier bridge (BD
2) the output high level, the first switching tube (S
1) conducting, make main switch (S
m) turn-off; When load links to each other with Switching Power Supply, the second rectifier bridge (BD
2) output low level, the first switching tube (S
1) turn-off, make main switch (S
m) conducting.
6. a kind of low standby loss control circuit of switching power supply that can detect load condition automatically according to claim 1 is characterized in that, the load condition testing circuit after the normal startup of described switching tube power supply is by diode (D), the first triode (Q
1), the second triode (Q
2), the 3rd triode (Q
3), the 3rd resistance (R
3), the 4th resistance (R
4), the 5th resistance (R
5), the 6th resistance (R
6), the 7th resistance (R
7) and optocoupler (OC) formation; The anode input of optocoupler (OC) and the 3rd triode (Q
3) collector electrode and resistance (R
4) an end link to each other negative electrode input and resistance (R
3) an end connect; Resistance (R
3) the other end and the 3rd triode (Q
3) emitter, the second triode (Q
2) emitter, the first triode (Q
1) emitter and the Switching Power Supply main circuit in sampling resistor (R
S) low level end link to each other; The 3rd triode (Q
3) the base stage and the second triode (Q
2) collector electrode, resistance (R
5) an end connect; Second triode (the Q
2) the base stage and the first triode (Q
1) collector electrode, resistance (R
6) an end link to each other the first triode (Q
1) base stage and anode, the resistance (R of diode (D)
7) an end connect; Resistance (R
4) the other end, resistance (R
5) the other end, resistance (R
6) the other end, resistance (R
7) the other end link to each other with the cathode output end of Switching Power Supply; The negative electrode of diode (D) and the cathode output end of Switching Power Supply, sampling resistor (R
S) the high level end link to each other.
7. a kind of low standby loss control circuit of switching power supply that can detect load condition automatically according to claim 6, it is characterized in that, the load condition testing circuit that described switching tube power supply is normal after starting when the Switching Power Supply band carries operate as normal, sampling resistor (R
S) on pressure drop be high level, the first triode (Q
1) conducting, the second triode (Q
2) turn-off the 3rd triode (Q
3) conducting, optocoupler (OC) ends, and output keeps high impedance, main switch (S
m) the maintenance conducting; If carve at a time and remove load, sampling resistor (R
S) on pressure drop become low level, the first triode (Q
1) turn-off diode (Q
2) conducting, the 3rd triode (Q
3) turn-off, optocoupler (OC) conducting, the output Low ESR is given main switch (S
m) gate voltage provides discharge loop; As main switch (S
m) gate voltage be reduced to its threshold voltage when following, main switch (S
m) turn-off.
8. according to each described a kind of low standby loss control circuit of switching power supply that can detect load condition automatically of claim 1～7, it is characterized in that the power supply of described control circuit is by the first electrodeless electric capacity (C
X1), the second electrodeless electric capacity (C
X2) and the first transformer (T
1) former limit winding, the second transformer (T
2) former limit winding dividing potential drop realize the first electrodeless electric capacity (C
X1) an end and the first transformer (T
1) end of the same name of former limit winding links to each other the first electrodeless electric capacity (C
X1) the other end with exchange input (L) bus and link to each other the first transformer (T
1) former limit winding the different name end with exchange input (N) bus and link to each other; Second electrodeless electric capacity (the C
X2) an end and the second transformer (T
2) end of the same name of former limit winding links to each other the first electrodeless electric capacity (C
X2) the other end with exchange input (N) bus and link to each other the second transformer (T
2) former limit winding the different name end with exchange input (N) bus and link to each other.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009202193997U CN201504186U (en) | 2009-10-12 | 2009-10-12 | Switch power supply low standby loss control circuit capable of automatically detecting load |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009202193997U CN201504186U (en) | 2009-10-12 | 2009-10-12 | Switch power supply low standby loss control circuit capable of automatically detecting load |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201504186U true CN201504186U (en) | 2010-06-09 |
Family
ID=42455114
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2009202193997U Expired - Lifetime CN201504186U (en) | 2009-10-12 | 2009-10-12 | Switch power supply low standby loss control circuit capable of automatically detecting load |
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| Country | Link |
|---|---|
| CN (1) | CN201504186U (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102035411A (en) * | 2010-07-19 | 2011-04-27 | 四川九州电子科技股份有限公司 | Single power supply buck standby circuit |
| CN102457184A (en) * | 2010-10-25 | 2012-05-16 | 盛群半导体股份有限公司 | Voltage conversion device |
| CN102625525A (en) * | 2011-01-31 | 2012-08-01 | 东芝照明技术株式会社 | Floodlight lighting apparatus, lighting device, and method for lighting floodlight |
| CN101674026B (en) * | 2009-10-12 | 2012-12-05 | 华南理工大学 | Low standby loss control circuit of switching power supply capable of automatically detecting load |
| CN109818569A (en) * | 2017-11-18 | 2019-05-28 | 丰郅(上海)新能源科技有限公司 | Method for being restarted after the parallel turning off system of photovoltaic module and shutdown |
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2009
- 2009-10-12 CN CN2009202193997U patent/CN201504186U/en not_active Expired - Lifetime
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101674026B (en) * | 2009-10-12 | 2012-12-05 | 华南理工大学 | Low standby loss control circuit of switching power supply capable of automatically detecting load |
| CN102035411A (en) * | 2010-07-19 | 2011-04-27 | 四川九州电子科技股份有限公司 | Single power supply buck standby circuit |
| CN102035411B (en) * | 2010-07-19 | 2012-12-05 | 四川九州电子科技股份有限公司 | Single power supply buck standby circuit |
| CN102457184A (en) * | 2010-10-25 | 2012-05-16 | 盛群半导体股份有限公司 | Voltage conversion device |
| CN102457184B (en) * | 2010-10-25 | 2014-02-26 | 盛群半导体股份有限公司 | Voltage conversion device |
| CN102625525A (en) * | 2011-01-31 | 2012-08-01 | 东芝照明技术株式会社 | Floodlight lighting apparatus, lighting device, and method for lighting floodlight |
| CN102625525B (en) * | 2011-01-31 | 2014-12-24 | 东芝照明技术株式会社 | Floodlight lighting apparatus, lighting device, and method for lighting floodlight |
| CN109818569A (en) * | 2017-11-18 | 2019-05-28 | 丰郅(上海)新能源科技有限公司 | Method for being restarted after the parallel turning off system of photovoltaic module and shutdown |
| CN109818569B (en) * | 2017-11-18 | 2021-06-08 | 丰郅(上海)新能源科技有限公司 | Parallel type turn-off system for photovoltaic module and method for restarting after turn-off |
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| C14 | Grant of patent or utility model | ||
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| AV01 | Patent right actively abandoned |
Granted publication date: 20100609 Effective date of abandoning: 20091012 |
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| RGAV | Abandon patent right to avoid regrant |