CN110460240A - A kind of digital synchronous rectifier switch power supply - Google Patents
A kind of digital synchronous rectifier switch power supply Download PDFInfo
- Publication number
- CN110460240A CN110460240A CN201910805340.4A CN201910805340A CN110460240A CN 110460240 A CN110460240 A CN 110460240A CN 201910805340 A CN201910805340 A CN 201910805340A CN 110460240 A CN110460240 A CN 110460240A
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- CN
- China
- Prior art keywords
- switch
- module
- signal
- power supply
- drive module
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- 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
- H02M3/33507—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 with automatic control of the output voltage or current, e.g. flyback converters
- H02M3/33515—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 with automatic control of the output voltage or current, e.g. flyback converters with digital control
-
- 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
-
- 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
- H02M1/00—Details of apparatus for conversion
- H02M1/0003—Details of control, feedback or regulation circuits
- H02M1/0012—Control circuits using digital or numerical techniques
-
- 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
- H02M1/00—Details of apparatus for conversion
- H02M1/0048—Circuits or arrangements for reducing losses
- H02M1/0054—Transistor switching losses
-
- 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
Abstract
The present invention relates to Switching Power Supplies, more particularly to a kind of digital synchronous rectifier switch power supply, including transformer, the armature winding of transformer makes the armature winding of transformer connect to the first switch tube of secondary windings transmission energy with for periodical on, off, the secondary windings of transformer is connected with the second switch for periodical on, off, output capacitance is in series between the secondary windings and second switch of transformer, first switch tube, second switch are respectively and for driving the first drive module of on, off, the second drive module to be connected；Technical solution provided by the invention can effectively overcome the biggish defect of power consumption present in the prior art.
Description
Technical field
The present invention relates to Switching Power Supplies, and in particular to a kind of digital synchronous rectifier switch power supply.
Background technique
For traditional Switching Power Supply, loss mainly includes three parts: the loss of primary switch pipe, high frequency transformer
Loss, the loss of secondary commutation diode, and in low-voltage, high-current occasion, the loss of secondary commutation diode occupies system
The overwhelming majority of loss, the effective ways for reducing rectifier loss are using synchronous rectification: using the metal-oxide-semiconductor of low on-resistance
Instead of traditional rectifier diode.Due to using synchronous rectifier, the control problem of synchronous rectifier is just brought.
In the Switching Power Supply of primary-side-control, the primary side winding of transformer is connected with main switch, and vice-side winding is connected with
Rectifier diode or synchronous switch pipe.Rectifier diode does not need additional control circuit, thus circuit structure is simple, rectifies two poles
The shortcomings that pipe is that itself pressure drop is larger, and the power consumption of Switching Power Supply is caused to increase, especially in the case of heavily loaded High-current output,
The power consumption of Switching Power Supply increases obvious.
Synchronous switch pipe can reduce the power consumption on rectifier cell, to improve the efficiency of Switching Power Supply.Synchronous switch
Pipe needs work asynchronously with main switch, could provide stable output voltage for load.Therefore, it is necessary to mention for synchronous switch pipe
For additional secondary side control circuit.However, secondary side control circuit itself can also generate power consumption, especially in the case where underloading,
Secondary side control circuit still works.
Summary of the invention
(1) the technical issues of solving
For disadvantages mentioned above present in the prior art, the present invention provides a kind of digital synchronous rectifier switch power supply, energy
It is enough effectively to overcome the biggish defect of power consumption present in the prior art.
(2) technical solution
In order to achieve the above object, the present invention is achieved by the following technical programs:
A kind of digital synchronous rectifier switch power supply, including transformer, the armature winding of the transformer with for periodically
On, off makes the armature winding of the transformer to the first switch tube series connection of secondary windings transmission energy, the transformation
The secondary windings of device is connected with the second switch for periodical on, off, the secondary windings of the transformer with it is described
Output capacitance is in series between second switch, the first switch tube, second switch are respectively and for driving on, off
The first drive module, the second drive module be connected；
First drive module, the second drive module include control module, the control module with for acquiring electricity
Voltage and be converted into the voltage sample conditioning module of low voltage signal in road and be connected, the control module in Acquisition Circuit
The electric current and current sample conditioning module for being converted into low current signal is connected, the control module be used to believe the low-voltage
Number, low current signal be converted into digital signal A/D conversion module be connected, the control module with for according to it is described number believe
Number generate and to drive the PMW of the PMW signal of the first switch tube or second switch that module occurs to be connected, the control module with
For the synchronous rectification module phase to the first switch tube or second switch to be rectified and exported to the PMW signal
Even, the control module be used to according to the PMW signal judge that the load detecting module of load condition is connected.
Preferably, the output end of the synchronous rectification module is connected with isolated drive circuit.
Preferably, the input terminal of the synchronous rectification module is connected with overcurrent protection module.
Preferably, the load detecting module detection in second drive module drives the PMW letter of the second switch
Number switch periods judge load condition.
Preferably, the load detecting module in second drive module is in the PMW signal for driving the second switch
Control under to square-wave signal carry out frequency division counter, judge the relationship of the switch periods and threshold value.
Preferably, when the switch periods are less than threshold value, the load detecting module in second drive module determines negative
It carries normal；When the switch periods are not less than threshold value, the load detecting module in second drive module determines in underloading
State.
Preferably, when the load detecting module in second drive module is determined in light condition, described second is driven
Dynamic model block disconnects the principal current of the second switch, and the second switch maintains on state by parasitic diode, together
When the first drive module in control module adjust driving first switch tube PMW signal switch periods, maintain output voltage
Constant.
(3) beneficial effect
Compared with prior art, a kind of digital synchronous rectifier switch power supply provided by the present invention has below beneficial to effect
Fruit:
1, controlling synchronous rectification module by control module can be realized the synchronously control of secondary commutation, and switch is effectively reduced
The power consumption of power supply, and the output end of synchronous rectification module is connected with isolated drive circuit, guarantees output effect, synchronous rectification mould
The input terminal of block is connected with overcurrent protection module, prevents Switching Power Supply from damaging because of overcurrent；
2, the switch periods of the PMW signal of the load detecting module detection driving second switch in the second drive module are come
Judge load condition, the load detecting module in the second drive module is right under the control of the PMW signal of driving second switch
Square-wave signal carries out frequency division counter, judges the relationship of switch periods and threshold value, the load detecting module in the second drive module is sentenced
When being in light condition surely, the second drive module disconnects the principal current of second switch, and second switch relies on parasitic diode
On state is maintained, while the control module in the first drive module adjusts the switch week of the PMW signal of driving first switch tube
Phase maintains output voltage constant, so as to which Switching Power Supply is effectively reduced in power consumption at light load.
Detailed description of the invention
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below
There is attached drawing needed in technical description to be briefly described.It should be evident that the accompanying drawings in the following description is only this
Some embodiments of invention for those of ordinary skill in the art without creative efforts, can be with
It obtains other drawings based on these drawings.
Fig. 1 is present system schematic diagram；
Fig. 2 is the first drive module, the system schematic of the second drive module in Fig. 1 of the present invention.
Specific embodiment
In order to make the object, technical scheme and advantages of the embodiment of the invention clearer, below in conjunction with the embodiment of the present invention
In attached drawing, technical scheme in the embodiment of the invention is clearly and completely described.Obviously, described embodiment is
A part of the embodiment of the present invention, instead of all the embodiments.Based on the embodiments of the present invention, those of ordinary skill in the art
Every other embodiment obtained without creative efforts, shall fall within the protection scope of the present invention.
A kind of digital synchronous rectifier switch power supply, as depicted in figs. 1 and 2, including transformer, the armature winding of transformer with
For periodical on, off the armature winding of transformer is become to the first switch tube series connection of secondary windings transmission energy
The secondary windings of depressor is connected with the second switch for periodical on, off, and the secondary windings of transformer is opened with second
It closes and is in series with output capacitance between pipe, first switch tube, second switch are respectively and for driving the first of on, off to drive
Module, the second drive module are connected；
First drive module, the second drive module include control module, control module with for voltage in Acquisition Circuit
And the voltage sample conditioning module for being converted into low voltage signal is connected, control module be used in Acquisition Circuit electric current and be converted into
The current sample conditioning module of low current signal is connected, control module be used to for low voltage signal, low current signal being converted into
The A/D conversion module of digital signal is connected, and control module drives first switch tube or second with for generating according to digital signal
The PMW of the PMW signal of switching tube occurs module and is connected, control module with for being rectified and being exported to first to PMW signal
The synchronous rectification module of switching tube or second switch is connected, control module with for according to PMW signal judging load condition
Load detecting module is connected.
The output end of synchronous rectification module is connected with isolated drive circuit.
The input terminal of synchronous rectification module is connected with overcurrent protection module.
Load detecting module detection in second drive module drives the switch periods of the PMW signal of second switch to sentence
Disconnected load condition.
Load detecting module in second drive module believes square wave under the control of the PMW signal of driving second switch
Number carry out frequency division counter, judge the relationship of switch periods and threshold value.
When switch periods are less than threshold value, the load detecting module in the second drive module determines that load is normal；Switch periods
When not less than threshold value, the load detecting module in the second drive module determines to be in light condition.
When load detecting module in second drive module is determined in light condition, the second drive module disconnects second and opens
The principal current of pipe is closed, second switch maintains on state, while the control mould in the first drive module by parasitic diode
Block adjusts the switch periods of the PMW signal of driving first switch tube, maintains output voltage constant.
Controlling synchronous rectification module by control module can be realized the synchronously control of secondary commutation, and switch electricity is effectively reduced
The power consumption in source, and the output end of synchronous rectification module is connected with isolated drive circuit, guarantees output effect, synchronous rectification module
Input terminal be connected with overcurrent protection module, prevent Switching Power Supply from damaging because of overcurrent.
Load detecting module detection in second drive module drives the switch periods of the PMW signal of second switch to sentence
Break load condition, the other side under the control of the PMW signal of driving second switch of the load detecting module in the second drive module
Wave signal carries out frequency division counter, judges the relationship of switch periods and threshold value, and the load detecting module in the second drive module determines
When in light condition, the second drive module disconnects the principal current of second switch, and second switch is tieed up by parasitic diode
On state is held, while the control module in the first drive module adjusts the switch periods of the PMW signal of driving first switch tube,
Output voltage constant is maintained, so as to which Switching Power Supply is effectively reduced in power consumption at light load.
When switch periods are less than threshold value, the load detecting module in the second drive module determines that load is normal；Switch periods
When not less than threshold value, the load detecting module in the second drive module determines to be in light condition.
It is worth noting that, the built-in system phase of the first drive module, the second drive module in technical scheme
It together, is system shown in Fig. 2.
The above embodiments are merely illustrative of the technical solutions of the present invention, rather than its limitations；Although with reference to the foregoing embodiments
Invention is explained in detail, those skilled in the art should understand that: it still can be to aforementioned each implementation
Technical solution documented by example is modified or equivalent replacement of some of the technical features；And these modification or
Replacement, can't be such that the essence of corresponding technical solution departs from the spirit and scope of the technical scheme of various embodiments of the present invention.
Claims (7)
1. a kind of digital synchronous rectifier switch power supply, including transformer, it is characterised in that: the armature winding and use of the transformer
In periodical on, off the armature winding of the transformer is connected to the first switch tube of secondary windings transmission energy,
The secondary windings of the transformer connect with the second switch for periodical on, off, the secondary of the transformer around
Output capacitance is in series between group and the second switch, the first switch tube, second switch are respectively and for driving
The first drive module, the second drive module of on, off are connected；
First drive module, the second drive module include control module, the control module in Acquisition Circuit
The voltage and voltage sample conditioning module for being converted into low voltage signal is connected, the control module with for electric current in Acquisition Circuit
And be converted into low current signal current sample conditioning module be connected, the control module with for by the low voltage signal,
The A/D conversion module that low current signal is converted into digital signal is connected, the control module with for according to the digital signal
Generation drives the PMW generation module of the PMW signal of the first switch tube or second switch to be connected, the control module and use
It is connected in being rectified and being exported to the PMW signal to the synchronous rectification module of the first switch tube or second switch,
The control module with for according to the PMW signal judging that the load detecting module of load condition is connected.
2. digital synchronous rectifier switch power supply according to claim 1, it is characterised in that: the synchronous rectification module it is defeated
Outlet is connected with isolated drive circuit.
3. digital synchronous rectifier switch power supply according to claim 1, it is characterised in that: the synchronous rectification module it is defeated
Enter end and is connected with overcurrent protection module.
4. digital synchronous rectifier switch power supply according to claim 1, it is characterised in that: in second drive module
The detection of load detecting module drives the switch periods of the PMW signal of the second switch to judge load condition.
5. digital synchronous rectifier switch power supply according to claim 4, it is characterised in that: in second drive module
Load detecting module carries out frequency division counter, judgement to square-wave signal in the case where driving the control of PMW signal of the second switch
The relationship of the switch periods and threshold value.
6. digital synchronous rectifier switch power supply according to claim 5, it is characterised in that: the switch periods are less than threshold value
When, the load detecting module in second drive module determines that load is normal；It is described when the switch periods are not less than threshold value
Load detecting module in second drive module determines to be in light condition.
7. digital synchronous rectifier switch power supply according to claim 6, it is characterised in that: in second drive module
When load detecting module is determined in light condition, second drive module disconnects the principal current of the second switch, institute
It states second switch and maintains on state by parasitic diode, while control module in the first drive module adjusts driving the
The switch periods of the PMW signal of one switching tube maintain output voltage constant.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910805340.4A CN110460240A (en) | 2019-08-29 | 2019-08-29 | A kind of digital synchronous rectifier switch power supply |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910805340.4A CN110460240A (en) | 2019-08-29 | 2019-08-29 | A kind of digital synchronous rectifier switch power supply |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110460240A true CN110460240A (en) | 2019-11-15 |
Family
ID=68489748
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910805340.4A Pending CN110460240A (en) | 2019-08-29 | 2019-08-29 | A kind of digital synchronous rectifier switch power supply |
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| Country | Link |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080192517A1 (en) * | 2007-02-12 | 2008-08-14 | Spi Electronic Co., Ltd. | Self-excitation synchronous rectification driver |
| CN101483395A (en) * | 2008-01-10 | 2009-07-15 | 电子科技大学 | Digital synchronous rectifying controller |
| EP2621069A2 (en) * | 2012-01-26 | 2013-07-31 | Linear Technology Corporation | Flyback converter with primary side voltage sensing and overvoltage protection during low load operation |
| CN103728572A (en) * | 2014-01-10 | 2014-04-16 | 矽力杰半导体技术(杭州)有限公司 | Load test method and test circuit and switching power supply utilizing same |
| CN106208714A (en) * | 2016-08-08 | 2016-12-07 | 杭州士兰微电子股份有限公司 | Synchronous rectifying switching power source and control method |
-
2019
- 2019-08-29 CN CN201910805340.4A patent/CN110460240A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080192517A1 (en) * | 2007-02-12 | 2008-08-14 | Spi Electronic Co., Ltd. | Self-excitation synchronous rectification driver |
| CN101483395A (en) * | 2008-01-10 | 2009-07-15 | 电子科技大学 | Digital synchronous rectifying controller |
| EP2621069A2 (en) * | 2012-01-26 | 2013-07-31 | Linear Technology Corporation | Flyback converter with primary side voltage sensing and overvoltage protection during low load operation |
| CN103728572A (en) * | 2014-01-10 | 2014-04-16 | 矽力杰半导体技术(杭州)有限公司 | Load test method and test circuit and switching power supply utilizing same |
| CN106208714A (en) * | 2016-08-08 | 2016-12-07 | 杭州士兰微电子股份有限公司 | Synchronous rectifying switching power source and control method |
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Application publication date: 20191115 |
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| RJ01 | Rejection of invention patent application after publication |