CN109861561A - A kind of Switching Power Supply - Google Patents
A kind of Switching Power Supply Download PDFInfo
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- CN109861561A CN109861561A CN201811652871.6A CN201811652871A CN109861561A CN 109861561 A CN109861561 A CN 109861561A CN 201811652871 A CN201811652871 A CN 201811652871A CN 109861561 A CN109861561 A CN 109861561A
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- transformer
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- 238000004804 winding Methods 0.000 claims abstract description 72
- 238000006243 chemical reaction Methods 0.000 claims abstract description 11
- 238000001914 filtration Methods 0.000 claims abstract description 10
- 239000003990 capacitor Substances 0.000 claims description 76
- 230000005611 electricity Effects 0.000 claims description 7
- 238000009413 insulation Methods 0.000 claims description 2
- 238000000034 method Methods 0.000 abstract description 11
- 230000002452 interceptive effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 1
- 230000003071 parasitic effect Effects 0.000 description 1
- 230000024241 parasitism Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
Abstract
The present invention relates to power technique fields, disclose a kind of Switching Power Supply, including sequentially connected current rectifying and wave filtering circuit, DC-DC conversion circuit and output circuit, the DC-DC conversion circuit includes transformer and control circuit, the control circuit is used to keep the stability of transformer output voltage, shield winding is provided in the transformer, the shield winding is set between the armature winding of transformer and secondary windings；Y capacitance is substituted by adding shield winding in transformer, and is aided with specific control circuit, makes the interference signal of primary and secondary generation that can all return to primary ground by shield winding, reduces the leakage current of Switching Power Supply, improve device security.
Description
Technical field
The present invention relates to power technique fields more particularly to a kind of Switching Power Supplies.
Background technique
Currently, Switching Power Supply is widely used in electronic equipment with the advantages that portable and smart, efficient, Switching Power Supply passes through switch
The switch motion of device high frequency can generate electromagnetic interference, to meet relevant laws and regulations to the regulation of electromagnetic interference, need using Y capacitance
Channel is provided to interference signal, has biggish leakage current using the Switching Power Supply of Y capacitance, can be produced applied to audio, video equipment
Life is interfered and safety is low.
Summary of the invention
It is a primary object of the present invention to propose a kind of Switching Power Supply, Y is substituted by adding shield winding in transformer
Capacitor, and it is aided with specific control circuit, make the interference signal of primary and secondary generation that can all return to primary ground by shield winding,
The leakage current for reducing Switching Power Supply, improves device security.
To achieve the above object, a kind of Switching Power Supply provided by the invention, including sequentially connected current rectifying and wave filtering circuit,
DC-DC conversion circuit and output circuit, the DC-DC conversion circuit include transformer and control circuit, and the control circuit is used
In being provided with shield winding in the stability for keeping transformer output voltage, the transformer, the shield winding is set to change
Between the armature winding and secondary windings of depressor.
Optionally, the current rectifying and wave filtering circuit includes: fuse F1, rectification chip BD1, capacitor C1, capacitor C2, inductance L1
It is connect with one end of inductance L2, fuse F1 with alternating current L, the other end of fuse F1 and an input terminal of rectification chip BD1
Connection, another input terminal of rectification chip BD1 are connect with alternating current N, an output end of rectification chip BD1 and the one of capacitor C1
End and the connection of one end of inductance L1, one end of the another output of rectification chip BD1 and the other end of capacitor C1 and inductance L2
Connection, the other end of inductance L1 are connect with one end of capacitor C2, and the other end of capacitor C2 is grounded together with the other end of inductance L2.
Optionally, the model RABF10 of the rectification chip BD1.
Optionally, the inductance L1 is colour loop inductance, and the inductance L2 is chip inductor.
Optionally, auxiliary winding is additionally provided in the transformer, the auxiliary winding is used to power to control circuit.
Optionally, the control circuit includes: resistance R3, resistance R4, resistance R5, resistance R6, resistance R8, resistance R10, electricity
Hinder R17, resistance R18, capacitor C3, capacitor C6, capacitor C7, diode D1, diode D2 and power supply chip U1；Wherein, resistance R4
One end be connected to together with one end of the capacitor C2 and one end of capacitor C6 transformer T1 armature winding one end, capacitor
The other end of C6 is connect with one end of the other end of resistance R4 and resistance R3, and the other end of resistance R3 and the cathode of diode D1 connect
It connecing, the other end of the anode and the armature winding of the pin 5,6 and transformer T1 of power supply chip U1 of diode D1 links together,
One end of the auxiliary winding of transformer T1 is connect with one end of the anode of diode D2 and resistance R6, the auxiliary winding of transformer T1
Other end ground connection, the cathode of diode D2 connect with one end of resistance R5, the other end of resistance R5 and one end of capacitor C3 and
The pin 1 of power supply chip U1 connects, the other end ground connection of capacitor C3, the other end of pin 2, the 3 and resistance R6 of power supply chip U1,
One end of one end of resistance R17, one end of resistance R18 and capacitor C7 links together, the other end and resistance R18 of resistance R17
The other end and the other end of capacitor C7 be grounded together；The one of the pin 4 of power supply chip U1 and one end of resistance R8 and resistance R10
End connection, the other end of resistance R8 are grounded together with the other end of resistance R10.
Optionally, the model SP2638F of the power supply chip U1.
Optionally, the output circuit includes: resistance R9, resistance R19, capacitor C4, capacitor C5, capacitor C9 and rectifying tube
D3, wherein the anode of one end of resistance R9 and rectifying tube D3 are connected to one end of the secondary windings of transformer T1, resistance R9 together
Other end connection capacitor C8 one end, the other end of capacitor C8 and the cathode of rectifying tube D3, one end of capacitor C4, capacitor C5
One end and one end of resistance R19 are connected together as output end, the other end of capacitor C4 and the other end, the resistance of capacitor C5
The other end of the secondary windings of the other end and transformer T1 of R19 is grounded together.
Optionally, the model DK45R10 of the rectifying tube D3.
Optionally, the transformer uses sequence winding, and the secondary windings of the transformer uses three layer insulation wire, described
Armature winding, auxiliary winding and shield winding all use enameled wire.
A kind of Switching Power Supply proposed by the present invention, including sequentially connected current rectifying and wave filtering circuit, DC-DC conversion circuit and defeated
Circuit out, the DC-DC conversion circuit include transformer and control circuit, and the control circuit is for keeping transformer output electricity
The stability of pressure, is provided with shield winding in the transformer, the shield winding be set to transformer armature winding and time
Between grade winding；Y capacitance is substituted by adding shield winding in transformer, and is aided with specific control circuit, is made primary and secondary
The interference signal of generation can all return to primary ground by shield winding, reduce the leakage current of Switching Power Supply, improve equipment peace
Quan Xing.
Detailed description of the invention
Fig. 1 is a kind of illustrative view of functional configuration of Switching Power Supply provided in an embodiment of the present invention；
Fig. 2 is a kind of circuit diagram of Switching Power Supply provided in an embodiment of the present invention；
Fig. 3 is Electromagnetic Interference Test figure provided in an embodiment of the present invention.
The embodiments will be further described with reference to the accompanying drawings for the realization, the function and the advantages of the object of the present invention.
Specific embodiment
It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, it is not intended to limit the present invention.
In subsequent description, it is only using the suffix for indicating such as " module ", " component " or " unit " of element
Be conducive to explanation of the invention, itself there is no specific meanings.Therefore, " module " can mixedly make with " component "
With.
Embodiment
As shown in Figure 1, in the present embodiment, a kind of Switching Power Supply, including sequentially connected current rectifying and wave filtering circuit, DC-DC
Conversion circuit and output circuit, the DC-DC conversion circuit include transformer and control circuit, and the control circuit is for keeping
The stability of transformer output voltage is provided with shield winding in the transformer, and the shield winding is set to transformer
Between armature winding and secondary windings.
In the present embodiment, Y capacitance is substituted by adding shield winding in transformer, and is aided with specific control electricity
Road makes the interference signal of primary and secondary generation that can all return to primary ground by shield winding, reduces the leakage current of Switching Power Supply,
Improve device security.
In the present embodiment, screen winding is equivalent to the function of two Y capacitances, and one is from armature winding to primary ground
Y capacitance, the other is Y capacitance of the secondary windings to primary ground, the interference signal of respectively primary and secondary generation provide channel,
Interference signal is guided into primary ground, and is consumed.And the leakage current very little between first, it is small to can ignore.This shielding around
Group design has passs to lay foundations, need to debug repeatedly find out this pass lay foundations could balance it is first for the first time between, generate primary and secondary
Interference signal primary ground can be all returned to by shield winding.
As shown in Fig. 2, in the present embodiment, the current rectifying and wave filtering circuit includes: fuse F1, rectification chip BD1, capacitor
One end of C1, capacitor C2, inductance L1 and inductance L2, fuse F1 are connect with alternating current L, the other end and rectification chip of fuse F1
An input terminal of BD1 connects, and another input terminal of rectification chip BD1 is connect with alternating current N, and one of rectification chip BD1 is defeated
Outlet is connect with one end of one end of capacitor C1 and inductance L1, and the another output of rectification chip BD1 is another with capacitor C1's
End and the connection of one end of inductance L2, the other end of inductance L1 are connect with one end of capacitor C2, the other end and inductance L2 of capacitor C2
The other end be grounded together.
In the present embodiment, current rectifying and wave filtering circuit exports a DC voltage, and the DC voltage is as DC-DC conversion circuit
Input.
In the present embodiment, the model RABF10 of the rectification chip BD1.
In the present embodiment, the inductance L1 is colour loop inductance, and the inductance L2 is chip inductor.
In the present embodiment, auxiliary winding is additionally provided in the transformer, the auxiliary winding is used for control circuit
Power supply.
In the present embodiment, the control circuit includes: resistance R3, resistance R4, resistance R5, resistance R6, resistance R8, resistance
R10, resistance R17, resistance R18, capacitor C3, capacitor C6, capacitor C7, diode D1, diode D2 and power supply chip U1；Wherein,
One end of resistance R4 is connected to the one of the armature winding of transformer T1 together with one end of the capacitor C2 and one end of capacitor C6
End, the other end of capacitor C6 are connect with one end of the other end of resistance R4 and resistance R3, the other end and diode D1 of resistance R3
Cathode connection, anode and the other end of the pin 5,6 of power supply chip U1 and the armature winding of transformer T1 of diode D1 connect
It is connected together, one end of the auxiliary winding of transformer T1 is connect with one end of the anode of diode D2 and resistance R6, transformer T1
Auxiliary winding other end ground connection, the cathode of diode D2 connect with one end of resistance R5, the other end and capacitor of resistance R5
One end of C3 and the pin 1 of power supply chip U1 connect, the other end ground connection of capacitor C3, the pin 2,3 and resistance of power supply chip U1
The other end of R6, one end of resistance R17, one end of resistance R18 and capacitor C7 one end link together, resistance R17's is another
End is grounded together with the other end of the other end of resistance R18 and capacitor C7；The pin 4 of power supply chip U1 and one end of resistance R8 and
One end of resistance R10 connects, and the other end of resistance R8 is grounded together with the other end of resistance R10.
In the present embodiment, the model SP2638F of the power supply chip U1.
In the present embodiment, the output circuit includes: resistance R9, resistance R19, capacitor C4, capacitor C5, capacitor C9 and whole
Flow tube D3, wherein the anode of one end of resistance R9 and rectifying tube D3 are connected to one end of the secondary windings of transformer T1, electricity together
Hinder one end of the other end connection capacitor C8 of R9, the other end and the cathode of rectifying tube D3, one end of capacitor C4, capacitor of capacitor C8
One end of C5 and one end of resistance R19 are connected together as output end, the other end of capacitor C4 and the other end, the electricity of capacitor C5
The other end for hindering the other end of R19 and the secondary windings of transformer T1 is grounded together.
In the present embodiment, the model DK45R10 of the rectifying tube D3.
In the present embodiment, the transformer uses sequence winding, and the secondary windings of the transformer is using three-layer insulated
Line, the armature winding, auxiliary winding and shield winding all use enameled wire.
It is illustrated in figure 3 the Electromagnetic Interference Test report that the Switching Power Supply using foregoing circuit is done, wherein Fig. 3-1 is
The electromagnetic interference of alternating current N line reports that Fig. 3-2 is that the electromagnetic interference of alternating current L line is reported, Fig. 3-3 is Radiative EMI report；By
Above it is found that the electromagnetic interference in Switching Power Supply is mainly derived from dV/dt and secondary commutation when primary metal-oxide-semiconductor HF switch acts
The di/dt of pipe switch motion.The interference signal that dV/dt is generated can pass to input terminal, while the parasitism for passing through T1 in the form of common mode
It is capacitively coupled to output end, similarly di/dt is similarly passed to output end in the form of common mode and passes to input by T1 parasitic capacitance
End, by the reasonable screen winding of design, the interfering energy for allowing dV/dt and di/dt to generate is arrived the present embodiment by transformer coupled
Shield winding passes to the ground of capacitor C2 in the form of differential mode, reasonably designs filter using inductance L1, L2 and shields interference signal
Firmly, prevent it from passing to input terminal by current rectifying and wave filtering circuit, allow interfering energy in primary principal current is returned with the shape of differential mode
Simultaneously Xiao consumes for formula flowing.
It should be noted that, in this document, the terms "include", "comprise" or its any other variant are intended to non-row
His property includes, so that the process, method, article or the device that include a series of elements not only include those elements, and
And further include other elements that are not explicitly listed, or further include for this process, method, article or device institute it is intrinsic
Element.In the absence of more restrictions, the element limited by sentence "including a ...", it is not excluded that including being somebody's turn to do
There is also other identical elements in the process, method of element, article or device.
The serial number of the above embodiments of the invention is only for description, does not represent the advantages or disadvantages of the embodiments.
Through the above description of the embodiments, those skilled in the art can be understood that above-described embodiment side
Method can be realized by means of software and necessary general hardware platform, naturally it is also possible to by hardware, but in many cases
The former is more preferably embodiment.Based on this understanding, technical solution of the present invention substantially in other words does the prior art
The part contributed out can be embodied in the form of software products, which is stored in a storage medium
In (such as ROM/RAM, magnetic disk, CD), including some instructions are used so that a terminal device (can be mobile phone, computer, clothes
Business device, air conditioner or the network equipment etc.) execute method described in each embodiment of the present invention.
The above is only a preferred embodiment of the present invention, is not intended to limit the scope of the invention, all to utilize this hair
Equivalent structure or equivalent flow shift made by bright specification and accompanying drawing content is applied directly or indirectly in other relevant skills
Art field, is included within the scope of the present invention.
Claims (10)
1. a kind of Switching Power Supply, which is characterized in that including sequentially connected current rectifying and wave filtering circuit, DC-DC conversion circuit and output
Circuit, the DC-DC conversion circuit include transformer and control circuit, and the control circuit is for keeping transformer output voltage
Stability, be provided with shield winding in the transformer, the shield winding is set to the armature winding and secondary of transformer
Between winding.
2. a kind of Switching Power Supply according to claim 1, which is characterized in that the current rectifying and wave filtering circuit includes: fuse
One end of F1, rectification chip BD1, capacitor C1, capacitor C2, inductance L1 and inductance L2, fuse F1 are connect with alternating current L, fuse
The other end of F1 is connect with an input terminal of rectification chip BD1, and another input terminal of rectification chip BD1 is connect with alternating current N,
An output end of rectification chip BD1 is connect with one end of one end of capacitor C1 and inductance L1, and another of rectification chip BD1 is defeated
Outlet is connect with one end of the other end of capacitor C1 and inductance L2, and the other end of inductance L1 is connect with one end of capacitor C2, capacitor
The other end of C2 is grounded together with the other end of inductance L2.
3. a kind of Switching Power Supply according to claim 2, which is characterized in that the model of the rectification chip BD1
RABF10。
4. a kind of Switching Power Supply according to claim 2, which is characterized in that the inductance L1 is colour loop inductance, the electricity
Sense L2 is chip inductor.
5. a kind of Switching Power Supply according to claim 2, which is characterized in that be additionally provided in the transformer auxiliary around
Group, the auxiliary winding are used to power to control circuit.
6. a kind of Switching Power Supply according to claim 5, which is characterized in that the control circuit includes: resistance R3, resistance
R4, resistance R5, resistance R6, resistance R8, resistance R10, resistance R17, resistance R18, capacitor C3, capacitor C6, capacitor C7, diode
D1, diode D2 and power supply chip U1；Wherein, one end of resistance R4 is together with one end of the capacitor C2 and one end of capacitor C6
The one end for being connected to one end of the armature winding of transformer T1, the other end of capacitor C6 and the other end of resistance R4 and resistance R3 connects
It connects, the other end of resistance R3 is connect with the cathode of diode D1, the anode of diode D1 and the pin 5,6 of power supply chip U1 and change
The other end of the armature winding of depressor T1 links together, one end of the auxiliary winding of transformer T1 and the anode of diode D2 and
One end of resistance R6 connects, the other end ground connection of the auxiliary winding of transformer T1, the cathode of diode D2 and one end of resistance R5
Connection, the other end of resistance R5 are connect with the pin 1 of one end of capacitor C3 and power supply chip U1, the other end ground connection of capacitor C3,
One end of the pin 2,3 of power supply chip U1 and the other end of resistance R6, one end of resistance R17, one end of resistance R18 and capacitor C7
It links together, is grounded together with the other end and the other end of the other end of resistance R18 and capacitor C7 of resistance R17；Power supply chip
The pin 4 of U1 is connect with one end of one end of resistance R8 and resistance R10, the other end of resistance R8 and the other end one of resistance R10
Play ground connection.
7. a kind of Switching Power Supply according to claim 6, which is characterized in that the model of the power supply chip U1
SP2638F。
8. a kind of Switching Power Supply according to claim 6, which is characterized in that the output circuit includes: resistance R9, resistance
R19, capacitor C4, capacitor C5, capacitor C9 and rectifying tube D3, wherein one end of resistance R9 is connect together with the anode of rectifying tube D3
To one end of the secondary windings of transformer T1, one end of the other end connection capacitor C8 of resistance R9, the other end of capacitor C8 with it is whole
The cathode of flow tube D3, one end of capacitor C4, one end of capacitor C5 and resistance R19 one end be connected together as output end, electricity
Hold the other end of C4 together with the other end of the secondary windings of the other end of capacitor C5, the other end of resistance R19 and transformer T1
Ground connection.
9. a kind of Switching Power Supply according to claim 8, which is characterized in that the model DK45R10 of the rectifying tube D3.
10. a kind of Switching Power Supply according to claim 1, which is characterized in that the transformer uses sequence winding, described
The secondary windings of transformer uses three layer insulation wire, and the armature winding, auxiliary winding and shield winding all use enameled wire.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811652871.6A CN109861561A (en) | 2018-12-29 | 2018-12-29 | A kind of Switching Power Supply |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811652871.6A CN109861561A (en) | 2018-12-29 | 2018-12-29 | A kind of Switching Power Supply |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109861561A true CN109861561A (en) | 2019-06-07 |
Family
ID=66893620
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811652871.6A Pending CN109861561A (en) | 2018-12-29 | 2018-12-29 | A kind of Switching Power Supply |
Country Status (1)
| Country | Link |
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| CN (1) | CN109861561A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111142041A (en) * | 2020-01-10 | 2020-05-12 | 上海力信电气技术有限公司 | Power supply testing device |
| CN111740615A (en) * | 2020-06-13 | 2020-10-02 | 深圳市海洋王照明工程有限公司 | Temperature and humidity detection device and switching power supply circuit thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101236827A (en) * | 2007-03-30 | 2008-08-06 | 广州市中奕通讯设备有限公司 | Method and product for solving the electromagnetic compatibility of no Y capacitance switch power transformer |
| US20110051467A1 (en) * | 2009-08-26 | 2011-03-03 | Sanken Electric Co., Ltd. | Resonant switching power supply device |
| CN206422702U (en) * | 2016-11-03 | 2017-08-18 | 东莞市盈聚电源有限公司 | Medical ultralow Leakage Current switching power circuit |
| CN206585480U (en) * | 2016-11-14 | 2017-10-24 | 东莞市盈聚电子有限公司 | A kind of low common-mode noise switching power circuit |
| CN209283117U (en) * | 2018-12-29 | 2019-08-20 | 深圳日辉达电源股份有限公司 | A kind of Switching Power Supply |
-
2018
- 2018-12-29 CN CN201811652871.6A patent/CN109861561A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101236827A (en) * | 2007-03-30 | 2008-08-06 | 广州市中奕通讯设备有限公司 | Method and product for solving the electromagnetic compatibility of no Y capacitance switch power transformer |
| US20110051467A1 (en) * | 2009-08-26 | 2011-03-03 | Sanken Electric Co., Ltd. | Resonant switching power supply device |
| CN206422702U (en) * | 2016-11-03 | 2017-08-18 | 东莞市盈聚电源有限公司 | Medical ultralow Leakage Current switching power circuit |
| CN206585480U (en) * | 2016-11-14 | 2017-10-24 | 东莞市盈聚电子有限公司 | A kind of low common-mode noise switching power circuit |
| CN209283117U (en) * | 2018-12-29 | 2019-08-20 | 深圳日辉达电源股份有限公司 | A kind of Switching Power Supply |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111142041A (en) * | 2020-01-10 | 2020-05-12 | 上海力信电气技术有限公司 | Power supply testing device |
| CN111740615A (en) * | 2020-06-13 | 2020-10-02 | 深圳市海洋王照明工程有限公司 | Temperature and humidity detection device and switching power supply circuit thereof |
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