CN106341048A - Constant voltage switch power supply - Google Patents
Constant voltage switch power supply Download PDFInfo
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- CN106341048A CN106341048A CN201610817295.0A CN201610817295A CN106341048A CN 106341048 A CN106341048 A CN 106341048A CN 201610817295 A CN201610817295 A CN 201610817295A CN 106341048 A CN106341048 A CN 106341048A
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- power supply
- switch
- constant
- voltage
- circuit
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Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33569—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
- H02M3/33576—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements having at least one active switching element at the secondary side of an isolation transformer
- H02M3/33592—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements having at least one active switching element at the secondary side of an isolation transformer having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer
Abstract
The invention discloses a constant voltage switch power supply. The power supply comprises a transformer (1), a main switch tube (Q1), a constant voltage controller (3), a power supply circuit (4), a feedback circuit (5), a current detection resistor (6) and a rectification filtering circuit (7). In the invention, the constant voltage controller is used to actively detect a work voltage provided by a power supply circuit in each switch period, and according to the size of the voltage, charging time of the power supply circuit is decided. When the work voltage provided by the power supply circuit is higher than a preset first reference voltage, the charging time is reduced. When the work voltage provided by the power supply circuit is lower than the preset first reference voltage, the charging time is increased. The work voltage provided by the power supply circuit does not change along with constant voltage switch power supply output power and complex design debugging of the power supply circuit is avoided. In addition, by using the constant voltage switch power supply, a requirement of constant voltage controller work voltage can be reduced; and a standard 5VCMOS technology can be used to manufacture the power supply and production cost is reduced.
Description
Technical field
The present invention relates to constant voltage switch power technology field, particularly to a kind of constant voltage Switching Power Supply.
Background technology
Fig. 1 is a kind of circuit diagram of typical constant voltage Switching Power Supply in prior art, in FIG, Isobarically Control chip 700
Electric power system be made up of assists winding na of resistance 640, electric capacity 650, fly-wheel diode 600 and transformator 100.Its work
Principle is: when constant voltage Switching Power Supply is just opened, electric capacity 650 is charged by resistance 640, and now Isobarically Control chip 700 is in
Stopped status；When the running voltage that electric capacity 650 provides rises to a certain voltage of Isobarically Control chip 700 inner setting, permanent
Pressure control chip 700 is started working, conducting power mos200, and the input winding np of transformator 100 starts to charge up, when input winding
After in np, primary current reaches a certain setting value, Isobarically Control chip 700 closes power mos 200, stores in input winding np
Energy will transition to export in winding ns and assists winding na, respectively output loading and Isobarically Control chip 700 are powered.Permanent
Pressure control chip 700 obtains output voltage situation by optocoupler 800, and determines to open according to output voltage situation next time
In the time of mos200 or input winding np, the peak value of primary current, goes round and begins again.Generally speaking Isobarically Control chip 700 does not have
The height of running voltage vcc being provided according to electric capacity 650 makes corresponding adjustment, the magnitude of voltage master of stable rear running voltage vcc
To be determined by output voltage vo, output umber of turn ns1 and assists winding number of turn na1, vcc ≈ vo*na1/ns1.But due to
Transformator 100 nonideality, the voltage of running voltage vcc not only changes with the change of output voltage, also with output electricity
Stream increase and increase, reduce with the reduction of output current.This lead to running voltage vcc voltage big under different loads
Amplitude of variation, and the operating voltage range of Isobarically Control chip 700 tends not to too greatly, this makes the design of this power supply circuits need
Repeatedly to attempt adjustment and can be only achieved preferable effect.
Content of the invention
In order to solve problem of the prior art, embodiments provide a kind of constant voltage Switching Power Supply.Described technical side
Case is as follows:
Embodiments provide a kind of constant voltage Switching Power Supply, comprising: transformator, main switch, constant-voltage controller, confession
Circuit, feedback circuit, current sense resistor, current rectifying and wave filtering circuit,
The positive pole of current rectifying and wave filtering circuit is connected with one end of input winding of transformator and the first end of power supply circuits respectively,
The negative pole of current rectifying and wave filtering circuit is connected with one end of current sense resistor and constant-voltage controller first pin respectively, and power supply circuits are defeated
Go out end to be connected with constant-voltage controller second pin, the other end of current sense resistor, the second end of power supply circuits and constant voltage control
Device the 4th pin common ground processed,
The other end that transformator inputs winding is connected with the colelctor electrode of main switch, and the base stage of main switch and emitter stage divide
It is not connected with the 5th pin of constant-voltage controller and the 6th pin,
The positive pole that transformator exports winding is connected with the first input end of feedback circuit, and positive pole is defeated with the second of feedback circuit
Enter end ground connection, the first outfan of feedback circuit is connected with the 7th pin of constant-voltage controller, the second output of constant-voltage controller
End ground connection,
Constant-voltage controller be used for the running voltage and default first reference voltage that are provided according to power supply circuits outfan it
Between relation, to control the charging interval of power supply circuits.
In the above-mentioned constant voltage Switching Power Supply of the embodiment of the present invention, described constant-voltage controller includes: integrator, the first blood pressure lowering
Device, the second reducing transformer, first comparator, the second comparator, logic circuit, drive circuit, current source, first switch, second open
Pass, the 3rd switch, the 4th switch,
The first input end of integrator is connected with the outfan of described power supply circuits, and its second input accesses default the
One reference voltage, its outfan is connected with logic circuit, and logic circuit generates the according to the first level signal that integrator exports
One control signal to control the charging interval of power supply circuits,
The normal phase input end of first comparator is connected with one end of current sense resistor, and its negative-phase input passes through series connection the
One reducing transformer is connected with the first outfan of feedback circuit, and its outfan is connected with logic circuit, and logic circuit is according to the first ratio
Compared with device output second electrical level signal generation second control signal to limit the maximum in power supply circuits charging interval,
The normal phase input end of the second comparator is connected with one end of current sense resistor, and its negative-phase input passes through series connection the
One reducing transformer and the second reducing transformer are connected with the first outfan of feedback circuit, and its outfan is connected with logic circuit, logic electricity
Road exports the 3rd control signal according to the three level signal that the second comparator exports, to open the charging of power supply circuits；
The also fixing output recurrent pulses control signal of logic circuit, to control the conducting of first switch, drive circuit divides
It is not connected with first switch, second switch, the 3rd switch, the control end of the 4th switch and logic circuit, for according to logic
The control signal of circuit output, controls first switch, second switch, the 3rd switch, the working condition of the 4th switch；
One end of first switch be connected with power supply circuits outfan by current source and its other end respectively with second switch
One end and the base stage of main switch connect, the other end of second switch ground connection, one end of the 3rd switch and power supply circuits export
End connects and its other end is connected with one end of the 4th switch, and the other end of the 4th switch is with the other end of current sense resistor altogether
With ground connection.
In the above-mentioned constant voltage Switching Power Supply of the embodiment of the present invention, also include: bleeder circuit, described bleeder circuit includes:
First resistor and second resistance, one end of first resistor is connected with one end of the assists winding of transformator, first resistor another
End is connected with one end of second resistance and the 8th pin of constant-voltage controller respectively, and the other end of second resistance is auxiliary with transformator
Help the other end common ground of winding.
In the above-mentioned constant voltage Switching Power Supply of the embodiment of the present invention, described constant-voltage controller also includes: the 3rd comparator, the
The negative-phase input of three comparators is connected with the other end of first resistor and one end of second resistance respectively, and the 3rd comparator is just
Phase input accesses default second reference voltage, and logic circuit is connected with the outfan of the 3rd comparator, for according to the 3rd
The three level signal of comparator output generates super pressure control signal, to realize the overpressure protection of constant voltage Switching Power Supply.
In the above-mentioned constant voltage Switching Power Supply of the embodiment of the present invention, the blood pressure lowering ratio of the first reducing transformer is 1/3, the second blood pressure lowering
The blood pressure lowering ratio of device is 9/10.
In the above-mentioned constant voltage Switching Power Supply of the embodiment of the present invention, described current rectifying and wave filtering circuit includes: rectifier bridge and first
Electric capacity, the input anode incoming transport power supply of rectifier bridge, the positive pole of the first electric capacity is connected with the output head anode of rectifier bridge, the
The negative pole of one electric capacity is all connected with one end of current sense resistor with rectification bridge output end negative pole.
In the above-mentioned constant voltage Switching Power Supply of the embodiment of the present invention, described power supply circuits include: 3rd resistor and the second electricity
Hold, one end that one end of 3rd resistor inputs winding with the positive pole of the first electric capacity and transformator respectively is connected, 3rd resistor another
One end is connected with the positive pole of the second electric capacity and the second pin of constant-voltage controller respectively, and the negative pole of the second electric capacity is electric with current detecting
The other end common ground of resistance.
In the above-mentioned constant voltage Switching Power Supply of the embodiment of the present invention, described feedback circuit includes: photoelectrical coupler and the 3rd
Electric capacity, the first input end of photoelectrical coupler is connected with the positive pole of the output winding of transformator, the second input of photoelectrical coupler
End ground connection, first outfan and the 3rd electric capacity of photoelectrical coupler the 4th pin common ground all with constant-voltage controller.
Technical scheme provided in an embodiment of the present invention has the benefit that
The running voltage that there is provided in each switch periods active detecting power supply circuits by constant-voltage controller is simultaneously big according to it
The little charging interval determining power supply circuits, when the running voltage voltage that power supply circuits provide is higher than default first reference voltage
Reduce the charging interval, when increasing charging when the running voltage voltage that power supply circuits provide is less than default first reference voltage
Between so that the running voltage voltage that provides of power supply circuits is not with the change of constant voltage Switching Power Supply output, it is to avoid power supply electricity
The loaded down with trivial details design debugging in road, additionally, this constant voltage Switching Power Supply can also reduce the requirement of constant-voltage controller running voltage so as to can
5v cmos technique using standard manufactures, and reduces the production cost of constant-current switch power source, also saves except existing constant voltage switch simultaneously
The assists winding in afterflow diode and transformator in power supply, has saved manufacturing cost.
Brief description
For the technical scheme being illustrated more clearly that in the embodiment of the present invention, will make to required in embodiment description below
Accompanying drawing be briefly described it should be apparent that, drawings in the following description are only some embodiments of the present invention, for
For those of ordinary skill in the art, on the premise of not paying creative work, other can also be obtained according to these accompanying drawings
Accompanying drawing.
Fig. 1 is a kind of circuit diagram of constant voltage Switching Power Supply that prior art provides；
Fig. 2 is a kind of circuit diagram of constant voltage Switching Power Supply provided in an embodiment of the present invention；
Fig. 3 is the voltage oscillogram of multiple nodes in a kind of constant voltage switching power circuit provided in an embodiment of the present invention.
Specific embodiment
For making the object, technical solutions and advantages of the present invention clearer, below in conjunction with accompanying drawing to embodiment party of the present invention
Formula is described in further detail.
Embodiment
Embodiments provide a kind of constant voltage Switching Power Supply, referring to Fig. 2, may include that transformator 1, main switch
Q1 (for audion), constant-voltage controller 3, power supply circuits 4, feedback circuit 5, current sense resistor 6, current rectifying and wave filtering circuit 7.
The positive pole of current rectifying and wave filtering circuit 7 input one end of winding np and the first end of power supply circuits 4 with transformator 1 respectively
Connect, the negative pole of current rectifying and wave filtering circuit 7 is connected with one end of current sense resistor 6 and constant-voltage controller 3 first pin vcs respectively
Connect, power supply circuits 4 outfan is connected with constant-voltage controller 3 second pin vcc, the other end of current sense resistor 6, power supply circuits
4 the second end and constant-voltage controller 3 the 4th pin gnd common ground, transformator 1 inputs the other end of winding np and master opens
The colelctor electrode closing pipe q1 connects, the base stage of main switch q1 and emitter stage respectively with the 5th pin vb of constant-voltage controller 3 and the
Six pin ve connect, and the positive pole that transformator 1 exports winding ns is connected with the first input end of feedback circuit 5, and positive pole is electric with feedback
Second input end grounding on road 5, the first outfan of feedback circuit 5 is connected with the 7th pin comp of constant-voltage controller 3, constant voltage
Second output head grounding of controller 3, constant-voltage controller 3 be used for according to power supply circuits 4 outfan provide voltage with default
Relation between first reference voltage, to control the charging interval of power supply circuits 4.
In the present embodiment, the pin that constant-voltage controller 3 uses be respectively the first pin vcs, second pin vcc, the
Four pin gnd, the 5th pin vb, the 6th pin ve, the 7th pin comp, the 8th pin dem.
Transformator 1 is used for inputting the input voltage of winding np according to it, controls the output voltage in its output winding ns；Main
Switching tube q1 is used for the dutycycle controlling transformator 1 to input input voltage (i.e. original edge voltage) in winding np, to adjust transformator 1
Output voltage；Power supply circuits 4 are used for providing running voltage for constant-voltage controller 3；Feedback circuit 5 is used for constant-voltage controller 3
Feedback transformer 1 exports the output voltage in winding ns；Current sense resistor 6 is used for providing and being detected for constant-voltage controller 3
Flow through input winding np in primary current ip.
Constant-voltage controller 3 is used for controlling main switch q1 on and off；The work providing according to power supply circuits 4 is provided
The relation of voltage (i.e. voltage at constant-voltage controller 3 second pin vcc) and default first reference voltage vref_vcc to be adjusted
The charging interval to power supply circuits 4 for the section, that is, when the running voltage voltage that power supply circuits provide is higher than default first reference voltage
Reduce the charging interval, when the running voltage voltage that power supply circuits provide is less than default first reference voltage during vref_vcc
Increase the charging interval during vref_vcc.
Specifically, referring to Fig. 2, constant-voltage controller 3 includes: integrator 31, the first reducing transformer 32, the second reducing transformer 33,
One comparator 34, the second comparator 35, logic circuit 36, drive circuit 37, current source ib, first switch k1, second switch k2,
3rd switch k3, the 4th switch k0.
The outfan of second pin vcc and power supply circuits 4 that the first input end of integrator 31 passes through constant-voltage controller 3 connects
Connect, its second input accesses default first reference voltage vref_vcc, its outfan is connected with logic circuit 36, logic electricity
Road 36 generates the first control signal to control filling of power supply circuits 4 according to the first level signal tch_min that integrator 31 exports
The electric time；
The normal phase input end of first comparator 34 passes through the first pin vcs and the current sense resistor 6 of constant-voltage controller 3
One end connects, and its negative-phase input passes through series connection the first reducing transformer 32 and is connected (Isobarically Control with the first outfan of feedback circuit 5
7th pin comp of device 3 is between the first reducing transformer 32 and the first outfan of feedback circuit 5), its outfan and logic
Circuit 36 connects, and logic circuit generates the second control signal to limit according to the second electrical level signal off that first comparator 34 exports
The maximum in power supply circuits 4 charging interval processed, also controls main switch q1 to close (the i.e. covert output voltage according to transformator 1
Control the dutycycle of main switch q1 so that the output voltage of transformator 1 keeps stable in each cycle)；
The normal phase input end of the second comparator 35 is also by the first pin vcs and the current sense resistor 6 of constant-voltage controller 3
One end connect, its negative-phase input pass through connect the first reducing transformer 32 and the second reducing transformer 33 defeated with the first of feedback circuit 5
Go out end connect (the 7th pin comp of constant-voltage controller 3 be in the first reducing transformer 32 and feedback circuit 5 the first outfan it
Between), its outfan is connected with logic circuit 36, the three level signal pre_ that logic circuit 36 exports according to the second comparator 35
Off exports the 3rd control signal, to open the charging of power supply circuits 4；
The also fixing output recurrent pulses control signal of logic circuit 36, (is controlled with the conducting controlling first switch k1
The conducting of main switch q1), drive circuit 37 respectively with first switch k1, second switch k2, the 3rd switch k3, the 4th switch k0
Control end and logic circuit 36 connect, for the control signal being exported according to logic circuit 36, control first switch k1,
Second switch k2, the 3rd switch k3, the working condition (being switched on or off) of the 4th switch k0；
Current source ib is passed through with second pin vcc of constant-voltage controller 3 (i.e. with power supply circuits 4 in one end of first switch k1
Outfan) connect and its other end be connected with one end of second switch k2 and the base stage of main switch q1 respectively, second switch
The other end ground connection of k2, one end of the 3rd switch k3 and second pin vcc (the i.e. output with power supply circuits 4 of constant-voltage controller 3
End) connect and its other end is connected with one end of the 4th switch k0, the 4th switchs the other end of k0 by constant-voltage controller 3 the
Four pin gnd and the other end common ground of current sense resistor 6.
In the present embodiment, when the conducting of first switch k1, second switch k2 closes, the 3rd switch k3 closes, the 4th switch
During k0 conducting, constant voltage Switching Power Supply is in normal power supply state；When the closing of first switch k1, second switch k2 closes, the 3rd opens
Close k3 conducting, the 4th switch k0 closes, in a period of main switch q1 late release, power supply circuits 4 are charged；When
When one switch k1 closes, second switch k2 turns on, main switch q1 closes.
Further, referring to Fig. 2, this constant voltage Switching Power Supply can also include: bleeder circuit 8, bleeder circuit 8 can wrap
Include: first resistor rf1 and second resistance rf2, one end of first resistor rf1 is connected with one end of assists winding na of transformator 1,
The other end of first resistor rf1 is connected with one end of second resistance rf2, the auxiliary of the other end of second resistance rf2 and transformator 1
The other end common ground of winding na.
Further, constant-voltage controller 3, can also include: the 3rd comparator 38, the negative-phase input of the 3rd comparator 38
It is connected with the other end of first resistor rf1 and one end of second resistance rf2 respectively by the 8th pin dem of constant-voltage controller 3,
The normal phase input end of the 3rd comparator 38 accesses default second reference voltage vref_dem, logic circuit 36 and the 3rd comparator
38 outfan connects, and the three level signal fb_ov for being exported according to the 3rd comparator 38 generates super pressure control signal, with
Realize the overpressure protection of constant voltage Switching Power Supply.
In the present embodiment, this constant voltage Switching Power Supply can be equipped with overpressure protection apparatus, including bleeder circuit 8 and the 3rd ratio
Compared with device 38 it is also possible to not be equipped with overpressure protection apparatus, such transformator 1 can save assists winding na, and of the prior art
Constant voltage Switching Power Supply then must possess assists winding (for controlling power supply circuits to charge), rather than as the constant voltage in the present embodiment is opened
Closing power supply equally can be according to practical situation unrestricted choice.
Alternatively, the blood pressure lowering ratio of the first reducing transformer 32 is 1/3, and the blood pressure lowering ratio of the second reducing transformer 33 is 9/10.I.e.
The absolute value of the voltage vref of one comparator 34 negative-phase input is absolute value of voltage at the 7th pin comp of constant-voltage controller 3
1/3, the absolute value of the voltage vref0 of the second comparator 35 negative-phase input is the voltage of first comparator 34 negative-phase input
The 9/10 of the absolute value of vref.
Specifically, referring to Fig. 2, current rectifying and wave filtering circuit 7 may include that rectifier bridge 71 and the first electric capacity cin, rectifier bridge 71
Input anode passes through to exchange input switch k incoming transport power supply, and the positive pole of the first electric capacity cin is rectified with the output of rectifier bridge 71
Pole connects, and the negative pole of the first electric capacity cin is all connected with one end of current sense resistor 6 with rectifier bridge 71 negative pole of output end.
In the present embodiment, the alternating current power supply accessing constant voltage Switching Power Supply passes through current rectifying and wave filtering circuit 7, can be exported
Smoothly unidirectional current, uses for subsequent conditioning circuit.
Further, power supply circuits 4 may include that 3rd resistor rst and the second electric capacity c0, one end of 3rd resistor rst
It is connected with the positive pole of the first electric capacity cin and one end of transformator 1 input winding np respectively, the other end of 3rd resistor rst is respectively
It is connected with the positive pole of the second electric capacity c0 and second pin vcc of constant-voltage controller 3, the negative pole of the second electric capacity c0 is electric with current detecting
The other end common ground of resistance 6.
In the present embodiment, power supply circuits 4 pass through the second electric capacity c0 provides running voltage, power supply electricity for constant-voltage controller 3
When charging in road 4, it is also to charge for the second electric capacity c0.3rd resistor rst is used for when constant voltage Switching Power Supply just starts, and is second
Electric capacity c0 charges, and now, constant-voltage controller 3 does not have started work.
Specifically, referring to Fig. 2, feedback circuit 5 may include that photoelectrical coupler 51 and the 3rd electric capacity 52, photoelectrical coupler
51 first input end is connected with the positive pole of the output winding ns of transformator 1, the second input end grounding of photoelectrical coupler 51, light
First outfan of electric coupler 51 and the 4th pin gnd common ground of the 3rd electric capacity equal 52 and constant-voltage controller 3.
In the present embodiment, transformator 1 is exported to constant voltage control by the Voltage Feedback of output in winding ns by feedback circuit 5
In 4th pin gnd of device 3 processed, provide with reference to electricity for the negative-phase input for first comparator 34 and the second comparator 35
Pressure.
With reference to Fig. 2 and Fig. 3, the working cycle process of brief description once constant voltage Switching Power Supply.
First, logic circuit 36 fixing output recurrent pulses control signal, drive circuit 37 is according to recurrent pulses control
Signal timing processed controls the voltage von1 of first switch k1 to be adjusted to high level, and meanwhile, drive circuit 37 also can control second to hold
Close k2 and close (voltage voff is adjusted to low level), control the 3rd switch k3 to close (voltage vch is adjusted to low level), control
Make the 4th switch k0 to open (voltage von0 is adjusted to high level), the base stage of such main switch q1 is connected with current source ib,
Main switch q1 turns on, the input winding np energising of transformator 1.
When constant voltage Switching Power Supply is started working, flow through the primary current ip of the input winding np of transformator 1, flow through master and open
Close pipe q1, the 6th pin ve of constant-voltage controller 3, the 4th switch k0, be grounded after the 4th pin gnd of constant-voltage controller 3, then
After passing through current sense resistor 6, a road enters the negative pole of the first electric capacity cin, and the first of another road entrance constant-voltage controller 3 draws
Foot vcs.Voltage at such first pin vcs reduces with the increase of primary current ip (because primary current ip can be the
A negative voltage is generated, the absolute value of this negative voltage increases with the increase of primary current ip) at one pin vcs.
When voltage at the first pin vcs is less than the voltage vref0 of negative-phase input of the second comparator 35, the second ratio
The three level signal pre_off exporting compared with device 35, to control drive circuit 36 to control the second electric capacity c0 to start to charge up, specially
Control first switch k1 to close (time delay closed due to audion, now main switch q1 is still conducting), control the 4th
Switch k0 closes, and controls the 3rd switch k3 to open.Now, primary current ip flow through the 6th pin ve of constant-voltage controller 3, the 3rd
After switch k3, second pin vcc of constant-voltage controller 3, enter into the second electric capacity c0, and the second electric capacity c0 is started to charge up.This
When, constant-voltage controller 3 can determine the charging to the second electric capacity c0 according to the first level signal tch_min of integrator 31 output
Time, specifically, work as the magnitude of voltage at second pin vcc (i.e. node vcc in Fig. 3) place of constant-voltage controller 3 than the first reference
When voltage vref_vcc is big, the charging interval reduces, and the magnitude of voltage at second pin vcc of constant-voltage controller 3 is than the first reference
Voltage vref_vcc hour, the charging interval increases.
And the primary current flowing through the second electric capacity c0 can first be grounded, then after flowing through current sense resistor 6, a road enters
The negative pole of the first electric capacity cin, another road enters the first pin vcs of constant-voltage controller 3.So when the second electric capacity c0 charges,
Voltage at first pin vcs is still reducing.
After terminating between when charging, drive circuit 36 starts to control the 3rd switch k3 to cut out and controls the 4th switch k0 to lead
Logical, now, primary current ip flows through the 6th pin ve of constant-voltage controller 3, the 4th switch k0, the 4th of constant-voltage controller 3 the draws
It is grounded after foot gnd, after then passing through current sense resistor 6, a road enters the negative pole of the first electric capacity cin, and another road enters permanent
First pin vcs of pressure controller 3.Voltage at such first pin vcs continues to reduce (principle is ibid).When the first pin
When voltage at vcs is less than the voltage vref of negative-phase input of first comparator 34, the second electricity of first comparator 34 output
Ordinary mail off, logic circuit 36 controls main switch q1 to close according to second electrical level signal off, and specially drive circuit 37 is controlled
Second switch k2 processed turns on so that the electric charge in main switch q1 base stage is released rapidly, and main switch q1 closes, main switch q1
After closing, primary current ip is not had to produce negative voltage at the first pin vcs so that the voltage at the first pin vcs is rapid
Go up.Now, the energy in the input winding np of transformator 1 is transformed in output loading, so goes round and begins again.
It should be noted that although the absolute value of the voltage vref0 of the second comparator 35 negative-phase input is first comparator
The 9/10 of the absolute value of voltage vref of 34 negative-phase inputs, but due to the electricity at the 7th pin comp of constant-voltage controller 3
Pressure is negative voltage as the voltage at its first pin vcs, and therefore, voltage vref0 is bigger than voltage vref on the contrary.
The embodiment of the present invention passes through the work electricity that constant-voltage controller provides in each switch periods active detecting power supply circuits
Pressure simultaneously determines charging interval of power supply circuits, when the running voltage voltage that power supply circuits provide is higher than default the according to its size
Reduce the charging interval, when the running voltage voltage that power supply circuits provide is less than default first reference voltage during one reference voltage
Increase the charging interval so that the running voltage voltage of power supply circuits offer, not with the change of constant voltage Switching Power Supply output, is kept away
Exempt from the loaded down with trivial details design debugging of power supply circuits, additionally it is possible to reduce the requirement of constant-voltage controller running voltage so as to can use
The 5v cmos technique of standard manufactures, and reduces the production cost of constant-current switch power source, also saves except existing constant voltage Switching Power Supply simultaneously
In afterflow diode and transformator in assists winding, saved manufacturing cost.
The foregoing is only presently preferred embodiments of the present invention, not in order to limit the present invention, all spirit in the present invention and
Within principle, any modification, equivalent substitution and improvement made etc., should be included within the scope of the present invention.
Claims (8)
1. a kind of constant voltage Switching Power Supply it is characterised in that include: transformator (1), main switch (q1), constant-voltage controller (3),
Power supply circuits (4), feedback circuit (5), current sense resistor (6), current rectifying and wave filtering circuit (7),
The positive pole of current rectifying and wave filtering circuit (7) respectively with one end of the input winding (np) of transformator (1) and power supply circuits (4)
One end connects, negative pole one end and the constant-voltage controller (3) first with current sense resistor (6) respectively of current rectifying and wave filtering circuit (7)
Pin (vcs) connects, and power supply circuits (4) outfan is connected with constant-voltage controller (3) second pin (vcc), current sense resistor
(6) the other end, the second end of power supply circuits (4) and constant-voltage controller (3) the 4th pin (gnd) common ground,
The other end that transformator (1) inputs winding (np) is connected with the colelctor electrode of main switch (q1), the base of main switch (q1)
Pole and emitter stage are connected with the 5th pin (vb) of constant-voltage controller (3) and the 6th pin (ve) respectively, transformator (1) output around
The positive pole of group (ns) is connected with the first input end of feedback circuit (5), the second input end grounding of positive pole and feedback circuit (5),
First outfan of feedback circuit (5) is connected with the 7th pin (comp) of constant-voltage controller (3), and the of constant-voltage controller (3)
Two output head groundings,
Constant-voltage controller (3) is used for the running voltage providing according to power supply circuits (4) outfan and default first reference voltage
Between relation, to control the charging interval of power supply circuits (4).
2. constant voltage Switching Power Supply according to claim 1 is it is characterised in that described constant-voltage controller (3) includes: integrator
(31), the first reducing transformer (32), the second reducing transformer (33), first comparator (34), the second comparator (35), logic circuit
(36), drive circuit (37), current source (ib), first switch (k1), second switch (k2), the 3rd switch (k3), the 4th switch
(k0),
The first input end of integrator (31) is connected with the outfan of described power supply circuits (4), and its second input accesses default
The first reference voltage, its outfan is connected with logic circuit (36), logic circuit (36) exported according to integrator (31)
One level signal generates the first control signal to control the charging interval of power supply circuits (4),
The normal phase input end of first comparator (34) is connected with one end of current sense resistor (6), and its negative-phase input passes through string
The first outfan joining the first reducing transformer (32) with feedback circuit (5) is connected, and its outfan is connected with logic circuit (36), logic
Second electrical level signal generation second control signal that circuit (36) exports according to first comparator (34) is to limit power supply circuits (4)
The maximum in charging interval,
The normal phase input end of the second comparator (35) is connected with one end of current sense resistor (6), and its negative-phase input passes through string
Join the first reducing transformer (32) and the second reducing transformer (33) is connected with the first outfan of feedback circuit (5), its outfan and logic
Circuit (36) connects, and logic circuit (36) generates the 3rd according to the three level signal that the second comparator (35) exports and controls letter
Number, to open the charging of power supply circuits (4)；
The also fixing output recurrent pulses control signal of logic circuit (36), to control the conducting of first switch (k1), drives electricity
Road (37) respectively with first switch (k1), second switch (k2), the 3rd switch (k3), the 4th switch (k0) control end and
Logic circuit (36) connects, and for the control signal exporting according to logic circuit (36), controls first switch (k1), second switch
(k2), the 3rd switch (k3), the working condition of the 4th switch (k0)；
One end of first switch (k1) is connected with power supply circuits (4) outfan by current source (ib) and its other end is respectively with
The base stage of one end of two switches (k2) and main switch (q1) connects, the other end ground connection of second switch (k2), the 3rd switch
(k3) one end is connected with power supply circuits (4) outfan and its other end is connected with one end of the 4th switch (k0), the 4th switch
(k0) the other end and the other end common ground of current sense resistor (6).
3. constant voltage Switching Power Supply according to claim 2 is it is characterised in that also include: bleeder circuit (8), described partial pressure
Circuit (8) includes: the auxiliary of first resistor (rf1) and second resistance (rf2), one end of first resistor (rf1) and transformator (1)
One end of winding (na) connects, other end one end and the constant-voltage controller with second resistance (rf2) respectively of first resistor (rf1)
(3) the 8th pin (dem) connects, the other end of the assists winding (na) of the other end of second resistance (rf2) and transformator (1)
Common ground.
4. constant voltage Switching Power Supply according to claim 3, it is characterised in that described constant-voltage controller (3), also includes: the
Three comparators (38), the negative-phase input other end and the second resistance with first resistor (rf1) respectively of the 3rd comparator (38)
(rf2) one end connects, and the normal phase input end of the 3rd comparator (38) accesses default second reference voltage, logic circuit (36)
It is connected with the outfan of the 3rd comparator (38), the three level signal for being exported according to the 3rd comparator (38) generates superpressure
Control signal, to realize the overpressure protection of constant voltage Switching Power Supply.
5. constant voltage Switching Power Supply according to claim 2 is it is characterised in that the blood pressure lowering ratio of the first reducing transformer (32) is 1/
3, the blood pressure lowering ratio of the second reducing transformer (33) is 9/10.
6. constant voltage Switching Power Supply according to claim 1 is it is characterised in that described current rectifying and wave filtering circuit (7) includes: rectification
Bridge (71) and the first electric capacity (cin), the input anode incoming transport power supply of rectifier bridge (71), the positive pole of the first electric capacity (cin)
Be connected with the output head anode of rectifier bridge (71), the negative pole of the first electric capacity (cin) and rectifier bridge (71) negative pole of output end all with electric
One end of stream detection resistance (6) connects.
7. constant voltage Switching Power Supply according to claim 6 is it is characterised in that described power supply circuits (4) include: 3rd resistor
(rst) and the second electric capacity (c0), one end of 3rd resistor (rst) is defeated with the positive pole of the first electric capacity (cin) and transformator (1) respectively
The one end entering winding (np) connects, other end positive pole and the Isobarically Control with the second electric capacity (c0) respectively of 3rd resistor (rst)
The second pin (vcc) of device (3) connects, the other end common ground of the negative pole of the second electric capacity (c0) and current sense resistor (6).
8. constant voltage Switching Power Supply according to claim 1 is it is characterised in that described feedback circuit (5) includes: photoelectric coupling
The output winding (ns) of device (51) and the 3rd electric capacity (52), the first input end of photoelectrical coupler (51) and transformator (1) is just
Pole connects, the second input end grounding of photoelectrical coupler (51), and the first outfan of photoelectrical coupler (51) and the 3rd electric capacity are equal
(52) the 4th pin (gnd) common ground with constant-voltage controller (3).
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| CN201610817295.0A CN106341048B (en) | 2016-09-12 | 2016-09-12 | A kind of constant pressure Switching Power Supply |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI812476B (en) * | 2022-05-13 | 2023-08-11 | 大陸商昂寶電子（上海）有限公司 | power converter |
| CN117498510A (en) * | 2024-01-03 | 2024-02-02 | 唐泽制动器(天津)有限公司 | Constant voltage charging circuit of electric vehicle battery |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102097937A (en) * | 2011-01-07 | 2011-06-15 | 日银Imp微电子有限公司 | Voltage stabilization type power supply transformation circuit |
| US20110273912A1 (en) * | 2009-12-30 | 2011-11-10 | Smart Power Solutions, Inc. | Switching mode power supply |
| CN103872921A (en) * | 2014-03-13 | 2014-06-18 | 辉芒微电子（深圳）有限公司 | Constant-current switching power supply and control method thereof |
-
2016
- 2016-09-12 CN CN201610817295.0A patent/CN106341048B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110273912A1 (en) * | 2009-12-30 | 2011-11-10 | Smart Power Solutions, Inc. | Switching mode power supply |
| CN102097937A (en) * | 2011-01-07 | 2011-06-15 | 日银Imp微电子有限公司 | Voltage stabilization type power supply transformation circuit |
| CN103872921A (en) * | 2014-03-13 | 2014-06-18 | 辉芒微电子（深圳）有限公司 | Constant-current switching power supply and control method thereof |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI812476B (en) * | 2022-05-13 | 2023-08-11 | 大陸商昂寶電子（上海）有限公司 | power converter |
| CN117498510A (en) * | 2024-01-03 | 2024-02-02 | 唐泽制动器(天津)有限公司 | Constant voltage charging circuit of electric vehicle battery |
| CN117498510B (en) * | 2024-01-03 | 2024-03-05 | 唐泽制动器(天津)有限公司 | Constant voltage charging circuit of electric vehicle battery |
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| CN106341048B (en) | 2018-10-12 |
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Address after: 518057, room 10, building 5-8, Changhong science and technology building, twelve South tech Road, Nanshan District Science Park, Shenzhen, Guangdong Patentee after: Huimang Microelectronics (Shenzhen) Co.,Ltd. Address before: 518057, room 10, building 5-8, Changhong science and technology building, twelve South tech Road, Nanshan District Science Park, Shenzhen, Guangdong Patentee before: FREMONT MICRO DEVICES (SZ) Ltd. |