CN203537596U - Micro power consumption LED illumination power supply - Google Patents

Abstract

Provided is a micro power consumption LED illumination power supply. A main circuit does not employ the PWM (pulse width modulation). The micro power consumption LED illumination power supply is characterized in that the micro power consumption LED illumination power supply comprises a voltage reduction circuit and a constant current circuit, a commercial power is connected to the voltage reduction circuit and outputs a direct current low voltage, and the direct current low voltage is connected to the constant current circuit, outputs a constant current and drives an LED to shine. According to the micro power consumption LED illumination power supply, the reduction of the luminescence efficiency due to over-high current or over-high temperature is prevented, a main device of the illumination power supply works at a power frequency and does not generate high frequency loss and EMI interferences, a luminous tube does not flash, and 90% of the cost, size, weight and power consumption are reduced compared with the conventional LED power supply.

Description

Micro-power consumption LED mains lighting supply

Technical field

The present invention relates to a kind of micro-power consumption LED mains lighting supply.

Background technology

Tradition LED mains lighting supply present situation, has three kinds of situations:

1) adopt resistance step-down, be mainly used in small-power illumination, efficiency is very low, is only 5% left and right;

2) adopt capacitance decompression, be mainly used in small-power illumination, power factor is very low, is only 5% left and right;

3) adopt Switching Power Supply mode, be mainly used in the larger illumination of power, efficiency and power factor are less than 80%.

Width modulation type switching power supply, for unipolarity rectangular pulse, its direct current average voltage Uo depends on the width of rectangular pulse, and pulse is wider, and its direct current average voltage level is just higher.Direct current average voltage Uo can be calculated by formula, i.e. Uo=Um * T1/T.In formula, Um is rectangular pulse maximum voltage value; T is the rectangular pulse cycle; T1 is rectangular pulse width.

As can be seen from the above equation, when Um and T are when constant, direct current average voltage Uo will be directly proportional to pulse width T 1.Like this, as long as make pulse duration with the increasing and narrow down of stabilized voltage power supply output voltage, just can reach the object of burning voltage.

The shortcoming of this pulse-width modulation type stabilized voltage power supply maximum is that efficiency is relatively low, and circuit is complicated, produces strong EMI and disturbs, and electrical network is caused to severe contamination.

LED mains lighting supply feature

From characteristic curve, can find out, after LED conducting, the tiny change of forward voltage will cause the very big variation of electric current, ambient temperature, LED ageing time etc. also will be affected, and the output of the light of LED is directly relevant to the electric current passing through, when input voltage, ambient temperature change, must keep keeping constant by the electric current of LED.

From characteristic curve, can find out, when LED junction temperature raises, the luminous intensity of its output will reduce, and vice versa, and when junction temperature rises to 100 while spending, the luminous intensity of White LED is down to initial value 80%.

Summary of the invention

Burst pulse before and after the sinusoidal wave zero crossing of micro-power consumption LED photo power utilization civil power, obtain suitable voltage, adopt the new method that produces constant current simultaneously, object is energy-conservation and environmental protection, for realizing intelligent control of LED, optimal design is proposed, for LED is used more superior guarantee is provided in different operating environment.Micro-power consumption LED mains lighting supply, has avoided because electric current is excessive or save warm too high reduction luminous efficiency; This mains lighting supply main device is operated in power frequency, does not produce high-frequency loss and EMI and disturbs, and luminous tube does not flash, and cost, volume, weight, power consumption are compared and all reduced 90% with traditional LED power supply.

Micro-power consumption LED mains lighting supply has comprised schematic circuit, symmetrical output circuit, transformer output circuit etc., is described in detail as follows:

Fig. 1 is the schematic circuit of micro-power consumption LED mains lighting supply, and V1 is amplitude 311V civil power, and driving signal V2, V3, V4, V5 is all the square wave of cycle 20ms, pulsewidth 1ms, delay time successively: 0ms, 9ms, 10ms, 19ms.Between positive half period, when the 1ms of sine voltage zero passage front and back, V2, V3 high level, civil power V1 forms loop by D1, NPN field effect transistor Q1, R5 to ground, get respectively the sine voltage in 1ms interval, forward sinusoidal wave zero passage front and back, two direct impulses in resistance R 5; Between negative half-cycle, when the 1ms of sine voltage zero passage front and back, V4, V5 low level, civil power V1 forms loop by D2, PNP field effect transistor Q2, R5 to ground, get respectively the sine voltage in 1ms interval, negative sense sinusoidal wave zero passage front and back, two direct impulses in resistance R 5 after one-period, obtain positive and negative four positive negative pulse stuffing voltages in resistance R 5.The potential pulse ripple obtaining in resistance R 5 is the some of sine voltage, and pulsewidth 1ms is positioned at before and after sinusoidal wave zero passage, and two unidirectional pulse ripples before and after zero passage, form a positive negative pulse stuffing ripple, pulsewidth 2ms, and adjacent two impulse waves are symmetrical about the longitudinal axis.

As shown in Fig. 2 simulation waveform, each point voltage of getting corresponding with the driving voltage of each power MOS pipe, it is all the 1ms spike before and after sinusoidal wave zero passage, at sinusoidal wave one-period, only get four peaking voltages that near 1ms zero passage is wide, sine voltage distortion can be do not caused, the sine waveform factor can be greatly improved on the contrary.

Electric network pollution, power factor is low, and main cause is that capacitive load causes, the feature of capacitive load is only to utilize near the interval voltage of sinusoidal crest, only have this interval just to have outflow of bus current, and rest interval does not have outflow of bus current completely, this just causes power factor low.This power supply utilizes near the interval voltage of sinusoidal wave trough just, makes this conventionally not have the interval that electric wave flows out also to have outflow of bus current completely, has not only developed a large treasure-house of the energy, greatly improves power factor and the electric network pollution degree of electrical network simultaneously.

Main circuit does not adopt PWM pulse-width modulation, and micro-power consumption LED mains lighting supply is comprised of reduction voltage circuit and constant-current circuit, and civil power enters reduction voltage circuit, output DC low-voltage, and DC low-voltage enters constant-current circuit, output constant current, driving LED is luminous:

Reduction voltage circuit comprises comparator LM339 and power MOS pipe Q1, diode D1, D2, D3, D4 forms rectifier bridge B1, the ac input end of rectifier bridge B1 meets synchronous sine wave signal V2, its direct current output plus terminal connecting resistance R3, its direct current output negative terminal connecting resistance R4, resistance R 3 and resistance R 4 series connection, its intermediate point connects the inverting input of comparator LM339, the anodal connecting resistance R1 of direct voltage V1, its negative pole connecting resistance R5, resistance R 1 and resistance R 5 series connection, its intermediate point connects the in-phase input end of comparator LM339, one positive pole of termination direct voltage V1 and the positive power source terminal of comparator LM339 of resistance R 2, the signal output part of its another termination comparator LM339, connect the grid of power MOS pipe Q1 simultaneously, diode D5, the positive pole of D6, the negative pole of direct voltage V1, the negative power end ground connection of comparator LM339, diode D5, D6, D7, D8 form rectifier bridge B2, the ac input end of rectifier bridge B2 meets civil power V2, and its direct current output plus terminal connects the drain electrode of power MOS pipe Q1, and its direct current output negative terminal connects power MOS pipe Q1 source electrode by resistance R 6, while ground connection, capacitor C 1 is in parallel with resistance R 6,

Constant-current circuit comprises power MOS pipe Q1, Q2 and transformer TX1, the minus earth of direct voltage V2, the drain electrode of its anodal former edge joint power MOS pipe by transformer TX1, power MOS pipe Q1, the parallel branch ground connection that the source electrode of Q2 consists of resistance (R12) and capacitor C 6, the minus earth of capacitor C 6, diode D9, D10, D11, D12 forms rectifier bridge B3, the ac input end of rectifier bridge B3 connects the secondary of transformer TX1, connect the parallel branch that capacitor C 3 and resistance R 2 form simultaneously, its direct current output plus terminal connects capacitor C 4, the positive pole of C5, while connecting resistance R5, its direct current output negative terminal connects the negative pole of capacitor C 4, connect the source electrode of power MOS pipe Q2 simultaneously, resistance R 5 and resistance R 13 series connection, intermediate point connects the positive pole of the utmost point pipe part of optocoupler 4N33 by resistance R 6, the negative pole of the diode part of optocoupler 4N33 is by resistance R 11 ground connection, the emitter of its triode part is by resistance R 10 ground connection, the collector electrode of its triode part connects power Vcc by resistance R 1, simultaneously by capacitor C 10 and voltage stabilizing didoe D5 ground connection, the plus earth of voltage stabilizing didoe, the minus earth of capacitor C 5, the pin INV of control chip UC1825 connects the emitter of the triode part of optocoupler 4N33, pin OUT-A connects the grid of power MOS pipe Q2, pin OUT-B connects the grid of the first power MOS pipe Q1.

Accompanying drawing explanation

Fig. 1 is the schematic circuit of micro-power consumption LED mains lighting supply;

Fig. 2 is the simulation waveform of each point voltage of schematic circuit of micro-power consumption LED mains lighting supply;

Fig. 3 is the simulation waveform of gate drive voltage

Fig. 4 is the simulation waveform of the upper output voltage V p of load resistance R1, R2, Vn;

Fig. 5 is the symmetrical output circuit of direct current;

Fig. 6 is the simulation waveform of symmetrical VD;

Fig. 7 is transformer output circuit;

Fig. 8 is each point voltage simulation waveform of transformer circuit;

Fig. 9 is drive signal generation circuit;

Figure 10 is the simulation waveform that drives signal;

Figure 11 is transformerless output circuit (reduction voltage circuit);

Figure 12 is the simulation waveform of step-down voltage

Figure 13 is symmetrical drive signal generation circuit

Figure 14 is the driving signal simulation waveform of Vc after commutation

Figure 15 is the two-way output circuit of transless

Figure 16 is output voltage simulation waveform

Figure 17 is transformer output circuit

Figure 18 is each point voltage simulation waveform

Figure 19, Figure 20 are the details of unidirectional and two-way output voltage simulation waveform

Figure 19 is the spike simulation waveform details that the steamed bun ripple after rectification cuts down;

Figure 20 is the spike simulation waveform details cutting down from sine wave

Figure 21 is constant-current circuit

Figure 23 is the side circuit that constant current produces

Figure 22 is the simulation waveform of constant-current circuit output current

Embodiment

Micro-power consumption LED mains lighting supply has been utilized near near the sine voltage (trough) in the minimum interval of alternating voltage zero-crossing just, suitably selects metal-oxide-semiconductor to drive the pulsewidth of signal, goes for how low voltage, how lowly just can have.When selecting to drive signal pulsewidth 0.5ms, output symmetrical voltage is 30V left and right, and this voltage also can obtain direct-flow positive voltage after rectification.

Fig. 3 is gate drive voltage V2, V3, V4, V5, simulation waveform, Fig. 4 is the simulation waveform of the upper output voltage V p of load resistance R1, R2, Vn.V2, V3, V4, V5 are interval selection pulses, can see, strobe pulse and output voltage tip interval are corresponding one by one.

Left figure transverse axis upper part signal V2, V3 are alternately, corresponding one by one with the forward output voltage producing in resistance R 5, and under left figure transverse axis, part signal V4, V5 are also alternately, corresponding one by one with the negative sense output voltage producing in resistance R 5.

Fig. 5 is the symmetrical output circuit of direct current, and two source electrodes of Q1, Q2 in Fig. 1 circuit, it separates, and uses large electric capacity in parallel with R5, R6 simultaneously.On resistance R 5, R6, obtain symmetrical direct voltage, Fig. 6 is its simulation waveform.

This circuit all reduces 90% except cost, volume, weight, power consumption, and safe and reliable, can obtain and input ac power auxiliary DC power supply altogether simultaneously, and this point is very important to many application.

Fig. 7 is transformer output circuit, circuit connecting and Fig. 1 be difference slightly: V2, V3 are the square-wave signals of frequency 50Hz, forward pulsewidth 1ms, difference time delay 0ms and 9ms, the 0ms of the positive half cycle of civil power and 9ms are constantly, Q2 saturation conduction, V1 forms loop by the drain-source utmost point of diode, Q2 in the body of former limit P1, the Q1 of transformer TX1 with ground, at transformer primary side, form direct impulse electric current, by magnetic induction, at the identical electric current of TX1 secondary also forming frequency, by D1-D4, form rectifier bridge, become VD Vo.

V4, V5 are the square-wave signals of frequency 50Hz, negative sense pulsewidth 1ms, difference time delay 10ms and 19ms, the 10ms of civil power negative half period and 19ms are constantly, Q1 saturation conduction, V1 forms loop by the drain-source utmost point of diode, Q1 in the body of former limit P1, the Q2 of transformer TX1 with ground, at transformer primary side, forms negative-going pulse electric current, by magnetic induction, at the identical electric current of TX1 secondary also forming frequency, by D1-D4, form rectifier bridge, become VD Vo.

By adjusting the pulsewidth of the no-load voltage ratio of TX1 and V2, V3, V4, V5, the amplitude of adjustable output voltage Vo, transformer output can be used on place that must voltage isolation.Because the former limit of TX1 input voltage is the pulse of positive negative direction, in former limit, there is no direct current composition, the voltage waveform that secondary forms is symmetric double sideband voltage, can adopt bridge rectifier.

Because the input voltage frequency of transformer TX1 is 50Hz, in power conversion, all devices are all operated in power frequency, do not produce high-frequency loss and EMI and disturb; Because the input voltage of transformer TX1 is spike, TX1 can adopt pulse transformer again, can further reduce cost and volume; Because the input voltage of transformer TX1 is Symmetrical pulse, can utilize 4 quadrants of magnetic core magnetization curve, can further reduce power consumption and volume.

Fig. 8 is each point voltage simulation waveform of transformer circuit, respectively output voltage V o, transformer secondary voltage Vs, can see, transformer secondary peak voltage is after magnetic coupling, form series of bilateral band harmonization component, after bridge rectifier filtering, formed DC power supply as shown in simulation waveform.

The side circuit of micro-power consumption LED mains lighting supply has comprised drive signal generation circuit, commutating circuit, symmetrical output circuit, transformerless circuit, has transformer circuit, constant current produces is circuit etc., is described in detail as follows:

Fig. 9 is drive signal generation circuit, after the whole bridge that civil power sine voltage V2 forms through D1-D4, steamed bun wave voltage is through resistance R 1, R4 dividing potential drop, be added in the end of oppisite phase of comparator U1, direct voltage V1 is added in the in-phase end of comparator U1 through resistance R 1, R5 dividing potential drop, suitably the size of regulation voltage R1, can regulate the direct voltage height that is added to comparator in-phase end, according to the performance of comparator and feature, the height of this direct voltage has determined the pulsewidth of output direct impulse Va.

Owing to being added in U1 end of oppisite phase, be forward steamed bun ripple, so at sinusoidal wave zero passage place, originally negative pulse occurs locally, all above transverse axis, the pulsewidth in each pulse is original twice now.

Figure 10 is the simulation waveform that drives signal, forms the pulse of twice pulsewidth in the front and back of zero crossing (N * 10ms), and Here it is interval selection pulse Vc selects sinusoidal wave difference interval, and this example is selected minizone, front and back, sinusoidal wave zero passage place.

Figure 11 is transformerless output circuit (reduction voltage circuit), driving signal (interval selection pulse) Vc that Fig. 9 produces, be added in the grid of Q1, the source electrode connecting resistance R6 of Q1, its drain electrode adds the steamed bun wave voltage after civil power V3 rectification, whenever civil power zero passage place, driving signal Vc is high level, Q1 conducting, and steamed bun ripple forms spike voltage by the drain-source utmost point of Q1 on R6, after driving signal Vc, Q1 cut-off.

Figure 12 is the simulation waveform of reduction voltage circuit, before and after zero crossing (N * 10ms), form spike output voltage, the amplitude of this pulse voltage is directly proportional to driving the pulsewidth of signal Vc, and the pulsewidth of Vc is directly proportional to the direct voltage that is added in Fig. 4 comparator U1 in-phase end, because this direct voltage is adjustable, so produce the amplitude of spike output voltage, be also adjustable.

As the symmetrical output dc voltage of Fig. 5, the large capacitor filtering of spike output voltage, can obtain the direct voltage Vo of different amplitudes.The direct voltage being obtained by transformerless output circuit (reduction voltage circuit),, through pwm power conversion, all devices are not all operated in power frequency, do not produce high-frequency loss and EMI and disturb, and efficiency approaches 100%, and power factor is 1 or is greater than 1.Power factor is greater than 1 and can be regarded as: this circuit not only guarantees that self power factor is 1, can also improve the power factor of other Sneak Circuits simultaneously, and two kinds of factors are added up, and power factor can be recognized for being greater than 1.

Figure 13 is symmetrical drive signal generation circuit, the commutating circuit (being actually a kind of square wave inverter circuit) that Q1-Q4 forms, unidirectional drive signal Vc is converted to two-way driving and advise signal Vcc, wherein V2, V3, V5, V6 are the square-wave signals of cycle 20ms, pulsewidth 1ms, V3, V5 time delay 10ms.

During front 10ms, Q1, Q4 conducting, unidirectional drive signal Vc passes through the drain-source utmost point of Q1, Q4,2 forward burst pulses of 10ms before resistance R 4 is to form; During rear 10ms, Q2, Q3 conducting, unidirectional drive signal Vc, by the drain-source utmost point of Q2, Q3, is 2 negative sense burst pulses that form rear 10ms in resistance R 4; Positive and negative four burst pulses of one-period have just been formed altogether.

Figure 14 is the driving signal simulation waveform of Vc after commutation, and 4 positive and negative burst pulses that form in each cycle, have formed a series of positive and negative driving signal Vcc.

Figure 15 is the two-way output circuit of transless, the positive and negative driving signal Vcc being formed by commutating circuit is added between the grid and source electrode of Q3, Q4, V4 is input civil power, when the positive half cycle of civil power, driving signal are timing, Q4 conducting, by diode, the drain-source utmost point of Q4, R5 in Q3 body, form loop with the civil power during driving signal corresponding, on R5, produce two positive spike voltages corresponding with driving signal; When civil power negative half period, drive signal when negative, Q3 conducting, forms loop with the civil power during driving signal corresponding by diode, the drain-source utmost point of Q3, R5 in Q4 body, produces two negative spike voltages corresponding with driving signal on R5; After one cycle, produce four positive and negative spike voltages corresponding with driving signal on R5, after this reciprocation cycle, produces a succession of positive and negative spike voltage.

Figure 16 is output voltage simulation waveform, and spike output voltage is corresponding one by one with driving signal Vcc, and this voltage strengthens capacitor filtering, can obtain symmetrical bidirectional DC voltage (as the simulation waveform of Fig. 2).

Figure 17 is transformer output circuit, removes the resistance R 5 in Figure 15, and increasing transformer TX1 and rectification circuit thereof is Figure 17, and Q3, Q4 conducting opportunity and current direction are identical with upper figure, no longer repeats.It should be noted that, what in transformer TX1, flow through is Symmetrical electric current, and magnetic core, in magnetization process, does not have remanent magnetism, can utilize four quadrants of magnetization curve simultaneously, needn't degaussing circuit, secondary can adopt bridge rectifier, and circuit is simple and reliable, electric energy loss is little, and efficiency is high, safe and reliable.

Figure 18 is each point voltage simulation waveform, is topmost output dc voltage Vo, and centre is driving voltage Vcc, transformer secondary voltage Vs below, secondary voltage Vs is double-side band pulse voltage, directly uses bridge circuit rectification, and former limit needn't degaussing circuit and DCR circuit.

Figure 19, Figure 20 are the details of unidirectional and two-way output voltage simulation waveform, Figure 19 is the spike voltage waveform cutting down on the steamed bun ripple after rectification, Figure 20 is the spike voltage waveform cutting down from sine wave, and its amplitude is decided by drive the width of signal.

Figure 21 is constant-current circuit, and establishing output-current rating is Io=20A, and V2 is input direct voltage, is the direct voltage Vo that adopts Figure 11, Figure 17 circuit to obtain.Control chip UC1825 output two-way complementary drive signal OUT-A, OUT-B, control the break-make of Q1, Q2, on resistance R 3, R11, produce pulsating current, after capacitor C 3 filtering, form direct current, UC1825 is by the voltage on chip 4N33 sense resistance R11, i.e. electric current I o in perception R3, R11 branch road, when this electric current is greater than rated current 20A, UC1825 adjusts the output pulse width of narrow OUT-A, OUT-B, recovers output current 20A; When this electric current is less than rated current 20A, UC1825 adjusts the output pulse width of wide OUT-A, OUT-B, recovers output current 20A.That is to say, no matter load is how many, and portion can, so that output current keeps rated value 20A, reach the effect of constant current output.

Figure 22 is the simulation waveform of constant-current circuit output current, and output current is 20A, and no matter load variations or input voltage change, and output current all can keep constant.

Figure 23 is the side circuit that constant current produces, and compares with Figure 21, and the direct voltage Vc that the secondary of TX1 produces is superimposed upon on input voltage Vi, forms Vh=Vi+Vc, by Vh, produces continuous current.

The principle that produces constant current is identical with Figure 11 circuit with process, no longer repeats herein.The essence of constant current output is: output current is constant, and such as 5A, output voltage is variable, and such as changing to 100V from 80V, at this moment load resistance will change to 20 Ω from 16 Ω.Output voltage V a in this circuit is set as 80V, meet the situation of least load 16 Ω, bucking voltage Vc is set as 20V, Vh=Va+Vc=80+20=100V, meet the situation of maximum load 20 Ω, when load resistance at 16 Ω when changing between 20 Ω, voltage changes between 80V-100V, and output current is constant, keep constant.

Because voltage Va=80V directly obtains from input voltage, do not participate in actual power conversion, there is no power loss, this part efficiency can regard 100% as, only have Vc=20V to obtain from power conversion, if this part conversion efficiency is 85%, conversion is exactly 97% (calculating is omitted) to the efficiency of complete machine

This circuit all reduces 90% except cost, body weight, power consumption, and safe and reliable, can obtain and input ac power auxiliary DC power supply altogether simultaneously, and this point is very important to many application.

1) there is no high-frequency loss, because main device is operated in power frequency.

2) operating voltage waveform is impulse wave, needn't Industrial Frequency Transformer.

3) for the sine wave of input, only get the most approaching zero very small portion voltage, in fact do not draw input power.

4) output dc voltage efficiency approaches 100%, and power factor approaches or is greater than 1.

Claims (1)

1. a micro-power consumption LED mains lighting supply, main circuit does not adopt PWM pulse-width modulation, it is characterized in that micro-power consumption LED mains lighting supply is comprised of reduction voltage circuit and constant-current circuit, civil power enters reduction voltage circuit, output DC low-voltage, and DC low-voltage enters constant-current circuit, output constant current, driving LED is luminous:

1) reduction voltage circuit comprises comparator LM339 and power MOS pipe Q1, first, two, three, four diode (D1, D2, D3, D4) form rectifier bridge B1, the ac input end of rectifier bridge B1 meets synchronous sine wave signal V2, its direct current output plus terminal connects the 3rd resistance (R3), its direct current output negative terminal connects the 4th resistance (R4), the 3rd resistance (R3) and the series connection of the 4th resistance (R4), its intermediate point connects the inverting input of comparator LM339, the positive pole of direct voltage V1 connects the first resistance (R1), its negative pole connects the 5th resistance (R5), the first resistance (R1) and the series connection of the 5th resistance (R5), its intermediate point connects the in-phase input end of comparator LM339, one positive pole of termination direct voltage V1 and the positive power source terminal of comparator LM339 of the second resistance (R2), the signal output part of its another termination comparator LM339, connect the grid of power MOS pipe Q1 simultaneously, the 5th, six diode (D5, D6) positive pole, the negative pole of direct voltage V1, the negative power end ground connection of comparator LM339, five, six, seven, eight diodes (D5, D6, D7, D8) form rectifier bridge B2, the ac input end of rectifier bridge B2 meets civil power V2, its direct current output plus terminal connects the drain electrode of power MOS pipe Q1, its direct current output negative terminal connects power MOS pipe Q1 source electrode by the 6th resistance (R6), while ground connection, capacitor C 1 is in parallel with the 6th resistance (R6),

2) constant-current circuit comprises first, two power MOS pipe (Q1, Q2) and transformer TX1, the minus earth of direct voltage V2, it is anodal by the former edge joint first of transformer TX1, two power MOS pipe (Q1, Q2) drain electrode, first, two power MOS pipe (Q1, Q2) the parallel branch ground connection that source electrode consists of the 12 resistance (R12) and the 6th electric capacity (C6), the minus earth of the 6th electric capacity (C6), the 9th, ten, 11, 12 diode (D9, D10, D11, D12) form rectifier bridge B3, the ac input end of rectifier bridge B3 connects the secondary of transformer TX1, connect the parallel branch that the 3rd electric capacity (C3) and the second resistance (R2) form simultaneously, its direct current output plus terminal connects the 4th, five electric capacity (C4, C5) positive pole, connect the 5th resistance (R5) simultaneously, its direct current output negative terminal connects the negative pole of the 4th electric capacity (C4), connect the source electrode of the second power MOS pipe (Q2) simultaneously, the 5th resistance (R5) and the series connection of the 13 resistance (R13), intermediate point connects the positive pole of the diode section of optocoupler 4N33 by the 6th resistance (R6), the negative pole of the diode section of optocoupler 4N33 is by the 11 resistance (R11) ground connection, the emitter of its triode portion is by the tenth resistance (R10) ground connection, the collector electrode of its triode portion connects power Vcc by the first resistance (R1), simultaneously by the tenth electric capacity (C10) and voltage stabilizing didoe D5 ground connection, the plus earth of voltage stabilizing didoe D5, the minus earth of the 5th electric capacity (C5), the pin INV of control chip UC1825 connects the emitter of the triode portion of optocoupler 4N33, pin OUT-A connects the grid of the second power MOS pipe (Q2), pin OUT-B connects the grid of the first power MOS pipe (Q1).

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