CN205584027U - Wide voltage output switching power supply's of high -efficient isolated form multichannel circuit topology structure - Google Patents
Wide voltage output switching power supply's of high -efficient isolated form multichannel circuit topology structure Download PDFInfo
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- CN205584027U CN205584027U CN201620280984.8U CN201620280984U CN205584027U CN 205584027 U CN205584027 U CN 205584027U CN 201620280984 U CN201620280984 U CN 201620280984U CN 205584027 U CN205584027 U CN 205584027U
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- 238000004804 winding Methods 0.000 claims description 7
- 230000005611 electricity Effects 0.000 claims description 6
- 230000000087 stabilizing effect Effects 0.000 description 6
- 238000005516 engineering process Methods 0.000 description 3
- 230000000295 complement effect Effects 0.000 description 2
- 238000002955 isolation Methods 0.000 description 2
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
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Abstract
The utility model relates to a wide voltage output switching power supply's of high -efficient isolated form multichannel circuit topology structure, including push -pull circuit, rectification filter circuit, synchronous Rectifier BUCK circuit and flyback converter, push -pull circuit's input links to each other with the power, and its output links to each other with rectification filter circuit's input, and rectification filter circuit's output links to each other with synchronous Rectifier BUCK circuit, flyback converter respectively, the output of synchronous Rectifier BUCK circuit is power low voltage output terminal, flyback converter's output is held for power high voltage output. The utility model discloses switching power supply topological structure adopts the fixed soft switch push -pull circuit of the big space rate ZVS topology to cascade mutually with synchronous Rectifier buck circuit, flyback converter, provides simultaneously that high efficiency low voltage and high current exports, high voltage output. Simplified whole circuit structure, the whole efficiency of circuit has obtained the promotion, and the volume has obtained reducing.
Description
Technical field
This utility model relates to switch power technology field, is specifically related to a kind of efficiently isolated multipath Width funtion defeated
Go out the circuit topological structure of Switching Power Supply.
Background technology
The circuit topological structure of Switching Power Supply is varied, and what application was wide at present is to include Unisolated switch
Electric source topology Buck circuit, Boost circuit, Buck-Boost circuit etc., isolating switch power topology normal shock
Circuit, circuit of reversed excitation, half-bridge circuit, full-bridge circuit, push-pull circuit etc..Unisolated switch electric source topology is imitated
Rate has efficiency and is better than the advantage of isolating switch power topology, but it is because the feature of non-isolated, needs every
Release power supply occasion is limited.Additionally, in switching power circuit topology, export occasion at low-voltage and high-current
Often use synchronous rectification, to improve switch power efficiency.Open in design isolated multipath Width funtion output
When closing power supply, typically frequently with multichannel isolating switch power topology, or use synchronous rectification and normal shock electricity
Road, circuit of reversed excitation, half-bridge circuit, full-bridge circuit, push-pull circuit are used in combination to improve efficiency, different groups
Suitable for different application scenarios.But it is complicated to there is circuit, volume is relatively big, the shortcomings such as delivery efficiency is relatively low.
Utility model content
The purpose of this utility model is to provide a kind of efficient isolated multipath Width funtion output switch power source
Circuit topological structure, simplifies integrated circuit structure, and the whole efficiency of circuit is improved, and volume obtains
Reduce.
For achieving the above object, this utility model have employed techniques below scheme:
The circuit topological structure of a kind of efficient isolated multipath Width funtion output switch power source, including recommending electricity
Road, current rectifying and wave filtering circuit, synchronous rectification BUCK circuit and circuit of reversed excitation, the input of described push-pull circuit
Being connected with power supply, its outfan is connected with the input of current rectifying and wave filtering circuit, and the output of current rectifying and wave filtering circuit divides
Not being connected with synchronous rectification BUCK circuit, circuit of reversed excitation, the outfan of described synchronous rectification BUCK circuit is
Power supply low-voltage output, the outfan of described circuit of reversed excitation is power supply high-voltage output end.
Described push-pull circuit includes transformator T1, VMOS pipe V1 and VMOS pipe V2, described transformator T1
The drain electrode with VMOS pipe V1 and VMOS pipe V2 respectively of armature winding two ends be connected, at the beginning of transformator T1
Level winding centre cap is connected with power supply, the source electrode of VMOS pipe V1 and the source grounding of VMOS pipe V2,
The control end that grid is late-class circuit of VMOS pipe V1 and VMOS pipe V2, the secondary coil of transformator T1
Two ends are the outfan of push-pull circuit.
Described current rectifying and wave filtering circuit includes inductance L1, diode D1, diode D2, electric capacity C1 and electric capacity
The input that anode is current rectifying and wave filtering circuit of C2, described diode D1 and diode D2, described diode
The negative electrode of D1 and diode D2 all one end with inductance L1 are connected, and the other end of inductance L1 is through electric capacity C2
It is connected with the secondary center tap of transformator T1, the secondary center tap ground connection of transformator T1,
One end of described electric capacity C1 is connected with the negative electrode of diode D1, the other end of electric capacity C1 and inductance L1 with
Node side between electric capacity C2 is the outfan of current rectifying and wave filtering circuit.
Described synchronous rectification BUCK circuit includes inductance L2, VMOS pipe V3, VMOS pipe V4 and electric capacity C3,
The source electrode of described VMOS pipe V3 is connected with the outfan of current rectifying and wave filtering circuit, its drain electrode successively through inductance L2,
Electric capacity C3 ground connection, the drain electrode of described VMOS pipe V4 is connected with the drain electrode of VMOS pipe V3, VMOS pipe V4
Source ground, the control end that grid is late-class circuit of VMOS pipe V3 and VMOS pipe V4, inductance L2
And the node between electric capacity C3 is the low-voltage output of power supply.
Described circuit of reversed excitation includes transformator T2, diode D3, VMOS pipe V5 and electric capacity C4, described change
The primary coil Same Name of Ends of depressor T2 and the source electrode of VMOS pipe V5 are connected with the outfan of current rectifying and wave filtering circuit,
The different name end of the primary coil of transformator T2 is connected with the drain electrode of VMOS pipe V5, the secondary wire of transformator T2
Circle different name end is connected with the anode of diode D3, and the negative electrode of diode D3 is power supply high-voltage output end, transformation
The Same Name of Ends ground connection of the secondary coil of device T2, one end of described electric capacity C4 is connected with the negative electrode of diode D3,
Its other end is connected with the secondary coil Same Name of Ends of transformator T2.
As shown from the above technical solution, this utility model has high efficiency fixing maximum duty cycle by employing
High efficiency synchronous rectification Buck circuit that ZVS Sofe Switch push-pull circuit and applicable low-voltage, high-current export, have
The technology that the circuit of reversed excitation of High voltage output combines, the isolated form designing applicable multiple-channel output application scenario is many
Have a lot of social connections the circuit topological structure of voltage output switch power source.This topological structure make use of the isolation of push-pull topology
Feature, it is achieved the isolation to input voltage, by pre-for input voltage voltage stabilizing to more low-voltage.Push-pull circuit uses
Fixing maximum duty cycle controls to realize peak efficiency, to rectification circuit outputting inductance, push-pull circuit VMOS
It is controlled switch time realizing ZVS Sofe Switch push-pull circuit.This push-pull circuit and the synchronous rectification of rear class
Buck circuit is implemented in combination with the efficient output of low pressure, is particularly suited for low-voltage, high-current occasion.Additionally, this pushes away
Draw circuit to combine with the circuit of reversed excitation of rear class, it is achieved High voltage output so that the design letter of high-voltage output circuit
Changing, the whole efficiency of circuit is improved, and volume is reduced.
Accompanying drawing explanation
Fig. 1 is circuit diagram of the present utility model.
Detailed description of the invention
Below in conjunction with the accompanying drawings this utility model is described further:
As it is shown in figure 1, the circuit topology of the efficient isolated multipath Width funtion output switch power source of the present embodiment
Structure, including push-pull circuit 1, current rectifying and wave filtering circuit 2, synchronous rectification BUCK circuit 3 and circuit of reversed excitation 4,
The input of push-pull circuit 1 is connected with power supply, and its outfan is connected with the input of current rectifying and wave filtering circuit 2,
The output of current rectifying and wave filtering circuit 2 is connected with synchronous rectification BUCK circuit 3, circuit of reversed excitation 4 respectively, synchronizes whole
The outfan of stream BUCK circuit 3 is power supply low-voltage output, and the outfan of circuit of reversed excitation 4 is power supply high pressure
Outfan.
This push-pull circuit 1 includes at the beginning of transformator T1, VMOS pipe V1 and VMOS pipe V2, transformator T1
The drain electrode with VMOS pipe V1 and VMOS pipe V2 respectively of level winding two ends is connected, the primary of transformator T1 around
Group switching centre tap is connected with power supply, the source electrode of VMOS pipe V1 and the source grounding of VMOS pipe V2, VMOS
The grid of pipe V1 and VMOS pipe V2 is connected with the control circuit of Switching Power Supply, the secondary coil of transformator T1
The outfan that two ends are push-pull circuit 1.This push-pull circuit 1 is for isolating the input voltage of input circuit
Pre-voltage stabilizing, to more low-voltage, uses fixing maximum duty cycle to control to realize peak efficiency, defeated to rectification circuit
Go out inductance, push-pull circuit VMOS is controlled realizing ZVS Sofe Switch push-pull circuit switch time.
Current rectifying and wave filtering circuit 2 includes inductance L1, diode D1, diode D2, electric capacity C1 and electric capacity C2,
The anode of diode D1 and diode D2 is connected with the secondary windings two ends of transformator T1 respectively, diode
The negative electrode of D1 and diode D2 all one end with inductance L1 are connected, and the other end of inductance L1 is through electric capacity C2
It is connected with the secondary center tap of transformator T1, the secondary center tap ground connection of transformator T1,
One end of electric capacity C1 is connected with the negative electrode of diode D1, the other end of electric capacity C1 and inductance L1 and electric capacity
Node side between C2 is the outfan of current rectifying and wave filtering circuit 2.
Synchronous rectification BUCK circuit 3 includes inductance L2, VMOS pipe V3, VMOS pipe V4 and electric capacity C3,
The source electrode of VMOS pipe V3 is connected with inductance L1, and its drain electrode is successively through inductance L2, electric capacity C3 ground connection, VMOS
The drain electrode of pipe V4 is connected with the drain electrode of VMOS pipe V3, the source ground of VMOS pipe V4, VMOS pipe V3 and
The grid of VMOS pipe V4 is that the control circuit with Switching Power Supply is connected, the joint between inductance L2 and electric capacity C3
Point is the low-voltage output of power supply.This synchronous rectification Buck circuit 3 is for by the output electricity of push-pull circuit 1
Pressure is converted into the low-voltage needed in circuit, it is achieved high efficiency low-voltage, high-current output function, simplifies simultaneously
The design of isolated form low voltage output switch power source, improves efficiency.Additionally, push-pull circuit 1 will input electricity
Press pre-voltage stabilizing to more low-voltage, reduce the input voltage of synchronous rectification Buck circuit 3, output voltage pressure
Difference, improves the work efficiency of low-voltage, high-current output.
Circuit of reversed excitation 4 includes transformator T2, diode D3, VMOS pipe V5 and electric capacity C4, transformator T2
Primary coil Same Name of Ends be connected with the source electrode of VMOS pipe V3, the different name end of the primary coil of transformator T2
Drain electrode with VMOS pipe V5 is connected, and the source electrode of VMOS pipe V5 is connected with electric capacity C1, the grid of VMOS pipe V5
Pole is connected with the control circuit of Switching Power Supply, the secondary coil different name end of transformator T2 and the sun of diode D3
The most connected, the negative electrode of diode D3 is power supply high-voltage output end, the Same Name of Ends of the secondary coil of transformator T2
Ground connection, one end of electric capacity C4 is connected with the negative electrode of diode D3, its other end and the secondary of transformator T2
Coil Same Name of Ends is connected.This push-pull circuit 4 is used for output voltage is converted into the high voltage needed in circuit,
The design making high-voltage output circuit simplifies, and the whole efficiency of circuit is improved, and volume is reduced.
Operation principle: the grid of power VMOS tube V1, V2 of push-pull circuit 1 is controlled by pulse width modulator and produces
Raw staggered complementary type fixes maximum duty cycle high-frequency pulse signal, and this signal controls VMOS pipe V1, V2
It is switched on or off, thus by energy time level from T1 primary transmission to T1, by current rectifying and wave filtering circuit 2 by energy
Amount is converted into direct voltage output, it is achieved the pre-voltage stabilizing of output voltage within the specific limits, carries to late-class circuit
For power supply.VMOS pipe V3 and V4 of synchronous rectification Buck circuit 3 is respectively by pulse width modulator control, arteries and veins
Wide manipulator produces staggered complementary type high-frequency pulse signal, this signal control VMOS pipe V3, V4 open or
Turn off, it is achieved by L2, C3, energy is transferred to power supply output Vo1, and this DC voltage is through feedback signal
After modulate circuit processes, by the dutycycle of pulse width modulator regulation high-frequency pulse signal, it is achieved low-voltage, high-current
The accurate voltage stabilizing of output voltage.The VMOS pipe V5 of circuit of reversed excitation 4 is by pulse width modulator control, pulsewidth modulation
Device produces high-frequency pulse signal, and this signal controls being switched on or off of VMOS pipe V5, it is achieved just energy leads to
Crossing T2 and be transferred to power supply output Vo2, this DC voltage is after feedback signal conditioning processing of circuit, by pulsewidth
The dutycycle of manipulator regulation high-frequency pulse signal, it is achieved the accurate voltage stabilizing of High voltage output voltage.
Based on this circuit topology, low-voltage, high-current output in the second level can use Multi-path synchronous rectification Buck circuit
Parallel connection, with the demand of satisfied different low-voltage, high-current outputs, second level High voltage output can use multichannel flyback electricity
Road is in parallel, with the demand of satisfied different High voltage outputs.
Embodiment described above is only to be described preferred implementation of the present utility model, the most right
Scope of the present utility model is defined, on the premise of without departing from this utility model design spirit, and this area
Various deformation that the technical solution of the utility model is made by those of ordinary skill and improvement, all should fall into this reality
In the protection domain determined with novel claims.
Claims (5)
1. a circuit topological structure for efficient isolated multipath Width funtion output switch power source, its feature exists
In: include push-pull circuit (1), current rectifying and wave filtering circuit (2), synchronous rectification BUCK circuit (3) and flyback
Circuit (4), the input of described push-pull circuit (1) is connected with power supply, its outfan and rectifying and wave-filtering electricity
The input on road (2) be connected, the output of current rectifying and wave filtering circuit (2) respectively with synchronous rectification BUCK circuit
(3), circuit of reversed excitation (4) be connected, the outfan of described synchronous rectification BUCK circuit (3) is that power supply is low
Pressure outfan, the outfan of described circuit of reversed excitation (4) is power supply high-voltage output end.
The circuit of efficient isolated multipath Width funtion output switch power source the most according to claim 1 is opened up
Flutter structure, it is characterised in that: described push-pull circuit (1) includes transformator T1, VMOS pipe V1 and VMOS
Pipe V2, the armature winding two ends of described transformator T1 respectively with VMOS pipe V1 and the drain electrode of VMOS pipe V2
Being connected, the armature winding centre cap of transformator T1 is connected with power supply, the source electrode of VMOS pipe V1 and VMOS
The control end that grid is late-class circuit of the source grounding of pipe V2, VMOS pipe V1 and VMOS pipe V2, becomes
The two ends of the secondary coil of depressor T1 are the outfan of push-pull circuit (1).
The circuit of efficient isolated multipath Width funtion output switch power source the most according to claim 1 is opened up
Flutter structure, it is characterised in that: described current rectifying and wave filtering circuit (2) includes inductance L1, diode D1, two poles
Pipe D2, electric capacity C1 and electric capacity C2, the anode of described diode D1 and diode D2 is current rectifying and wave filtering circuit
Input, the negative electrode of described diode D1 and diode D2 all one end with inductance L1 are connected, inductance
The other end of L1 is connected through the secondary center tap of electric capacity C2 with transformator T1, and transformator T1's is secondary
Level winding centre cap ground connection, one end of described electric capacity C1 is connected with the negative electrode of diode D1, electric capacity C1
The other end and inductance L1 and electric capacity C2 between the outfan that node side is current rectifying and wave filtering circuit (2).
The circuit of efficient isolated multipath Width funtion output switch power source the most according to claim 1 is opened up
Flutter structure, it is characterised in that: described synchronous rectification BUCK circuit (3) include inductance L2, VMOS pipe V3,
VMOS pipe V4 and electric capacity C3, the source electrode of described VMOS pipe V3 and the outfan of current rectifying and wave filtering circuit (2)
Being connected, its drain electrode is successively through inductance L2, electric capacity C3 ground connection, the drain electrode of described VMOS pipe V4 and VMOS
The drain electrode of pipe V3 is connected, and the source ground of VMOS pipe V4, the grid of VMOS pipe V3 and VMOS pipe V4 is
The control end of late-class circuit, the node between inductance L2 and electric capacity C3 is the low-voltage output of power supply.
The circuit of efficient isolated multipath Width funtion output switch power source the most according to claim 1 is opened up
Flutter structure, it is characterised in that: described circuit of reversed excitation (4) includes transformator T2, diode D3, VMOS
The primary coil Same Name of Ends of pipe V5 and electric capacity C4, described transformator T2 and the source electrode of VMOS pipe V5 and rectification
The outfan of filter circuit (2) is connected, and the different name end of the primary coil of transformator T2 is with VMOS pipe V5's
Drain electrode is connected, and the secondary coil different name end of transformator T2 is connected with the anode of diode D3, diode D3
Negative electrode be power supply high-voltage output end, the Same Name of Ends ground connection of the secondary coil of transformator T2, described electric capacity C4
One end be connected with the negative electrode of diode D3, its other end is connected with the secondary coil Same Name of Ends of transformator T2.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620280984.8U CN205584027U (en) | 2016-04-05 | 2016-04-05 | Wide voltage output switching power supply's of high -efficient isolated form multichannel circuit topology structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620280984.8U CN205584027U (en) | 2016-04-05 | 2016-04-05 | Wide voltage output switching power supply's of high -efficient isolated form multichannel circuit topology structure |
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| Publication Number | Publication Date |
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| CN205584027U true CN205584027U (en) | 2016-09-14 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201620280984.8U Expired - Fee Related CN205584027U (en) | 2016-04-05 | 2016-04-05 | Wide voltage output switching power supply's of high -efficient isolated form multichannel circuit topology structure |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105680700A (en) * | 2016-04-05 | 2016-06-15 | 中国电子科技集团公司第四十三研究所 | High-efficiency isolated-type multipath wide voltage output switching power supply circuit topological structure |
| CN111313717A (en) * | 2020-03-31 | 2020-06-19 | 西安微电子技术研究所 | Power MOS voltage expansion circuit of switching power supply |
-
2016
- 2016-04-05 CN CN201620280984.8U patent/CN205584027U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105680700A (en) * | 2016-04-05 | 2016-06-15 | 中国电子科技集团公司第四十三研究所 | High-efficiency isolated-type multipath wide voltage output switching power supply circuit topological structure |
| CN111313717A (en) * | 2020-03-31 | 2020-06-19 | 西安微电子技术研究所 | Power MOS voltage expansion circuit of switching power supply |
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| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20160914 |