CN108173435A - Switching Power Supply control unit and the adaptive the lowest point lock-in circuit of Quasi-resonant switching power supply - Google Patents
Switching Power Supply control unit and the adaptive the lowest point lock-in circuit of Quasi-resonant switching power supply Download PDFInfo
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- CN108173435A CN108173435A CN201810128823.0A CN201810128823A CN108173435A CN 108173435 A CN108173435 A CN 108173435A CN 201810128823 A CN201810128823 A CN 201810128823A CN 108173435 A CN108173435 A CN 108173435A
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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
- H02M3/33507—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
- H02M3/33523—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 galvanic isolation between input and output of both the power stage and the feedback loop
-
- 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
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
-
- 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
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/4815—Resonant converters
-
- 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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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Dc-Dc Converters (AREA)
Abstract
The present invention provides a kind of adaptive the lowest point lock-in circuit of Quasi-resonant switching power supply, including：Input rectifying filter circuit, Switching Power Supply control unit, transformer T206, output rectifier and filter, output feedback circuit, power tube N1, primary current sampling resistor Rcs；The positive output termination transformer T206 primary side winding different names end of input rectifying filter circuit, negative output termination primary side；The current input terminal of transformer T206 primary side windings termination power tube N1 of the same name, the current output terminal of power tube N1 connect primary current sampling resistor Rcs one end, and primary current sampling resistor Rcs is another with terminating primary side；In-phase input end connection primary current sampling resistor Rcs one end of peak point current comparator U230；The switch control terminal of the output termination power tube N1 of driving circuit U231；The vice-side winding of transformer T206 connects output rectifier and filter；The circuit avoids the abnormal sound problem for transformer being caused to be generated by vibration due to switching frequency variation is excessive caused by sampling error.
Description
Technical field
The invention belongs to integrated circuit fields；More specifically, the present invention provides a kind of novel Quasi-resonant switching power supplies
Adaptive the lowest point lock-in circuit more particularly to inverse-excitation type switch power-supply control technology.
Background technology
With the implementation of new Energy Efficiency Standard and the continuous promotion of electronic product performance, transfer efficiency, work(to Switching Power Supply
Rate density is put forward higher requirements, and more and more harsh to the system cost control of Switching Power Supply, therefore improves Switching Power Supply
Transfer efficiency cannot be implemented simply by increasing the modes such as cost.Generally start currently on the market using quasi-resonance valley conduction
Technology reduces switching loss of the power tube in switching process, improves the transfer efficiency of system, reduces system Wen Sheng, improves production
Reliability of product etc..
However there is also defects for quasi-resonance valley conduction technology itself, are easy to cause the abnormal sound generated due to transformer vibrates
Phenomenon or EMI performances it is practical be deteriorated the problems such as.Switching frequency is discontinuous when problem above is primarily due to valley conduction
And since sampling deviation leads to the lowest point switching, amplitude is excessive causes.Quasi-resonance the lowest point skill is used currently on the market
The product generally existing above problem of art.
It is high to adapt to Switching Power Supply high-frequency small size because switching loss can be greatly reduced for quasi-resonance valley conduction technology
The development trend of power density, the following mainstream control technology that will become Switching Power Supply, therefore quasi-resonance valley conduction technology
Itself there are the defects of have to solve.
Invention content
It is an object of the present invention to overcome the shortcomings of the prior art and provide a kind of Quasi-resonant switching power supply is adaptive
The lowest point lock-in circuit, solve Quasi-resonant switching power supply due to when the lowest point switches switching frequency variation it is excessive and cause transformer because
Vibrate the abnormal sound problem generated.The technical solution adopted by the present invention is：
A kind of Switching Power Supply control unit, including：
Sampling and keep module U221, error amplifier U223, saw-toothed wave generator U224, PWM comparator U225, quasi-resonance
The lowest point comparator U242, NOT gate U243, nor gate U227, the enabled module U229 of the lowest point locking, the lowest point locking module U228, switch
Latch U232, driving circuit U231, peak point current comparator U230；
The input terminal of sampling and keep module U221, the in-phase input end of quasi-resonance the lowest point comparator U242 are auxiliary for connecing respectively
Winding is helped to divide feedback signal；The inverting input of the output termination error amplifier U223 of sampling and keep module U221, error
The in-phase input end reference voltage signal V of amplifier U223th_FB；The output signal Comp of error amplifier U223 meets PWM and compares
The inverting input of device U225, the output of saw-toothed wave generator U224 connect the in-phase input end of PWM comparators U225；PWM compares
An input terminal of the output termination nor gate U227 of device U225；
The anti-phase input termination the lowest point discrimination standard signal V of quasi-resonance the lowest point comparator U242th_DEM；Quasi-resonance the lowest point ratio
Another input terminal of output termination nor gate U227 and the input terminal of NOT gate U243 compared with device U242；Nor gate U227's is defeated
Go out, the output signal QR of NOT gate U243 inputs the lowest point locking module U228 respectively；
Error amplifier output signal Comp and power tube switching signal On inputs the enabled module U229 of the lowest point locking respectively,
The lowest point locking enable signal LockEn inputs the lowest point locking module U228 that locking enabled module U229 in the lowest point is generated；Power tube is opened
OFF signal On inputs the lowest point locking module U228；The power tube conducting trigger signal of the lowest point locking module U228 output terminals output
The S ends of ONset input switch latch U232；It is rest-set flip-flop to switch latch U232, and the R of switch latch U232 terminates peak
It is worth the output terminal of current comparator U230；The in-phase input end of peak point current comparator U230 is electric for connecting primary current sampling
Hinder Rcs one end, anti-phase input termination peak point current reference signal Vth_CS；
Switch the Q ends output power pipe switching signal On of latch U232, power tube switching signal On input driving circuits
The input terminal of U231, the output terminal of driving circuit U231 are used to connect the switch control terminal of power tube N1.
Further, locking enabled module U229 in the lowest point includes：MOS switch K321, K322, phase inverter U313, capacitance
C323, C324, isolation buffer amplifier U331, positive voltage bias V332, negative voltage bias V333, hysteresis comparator U334,
U335, nor gate U336, counter U337；
Power tube switching signal On connects the control terminal of MOS switch K321 and the input terminal of phase inverter U313；Error amplifier
The output signal Comp of U223 connects one end of MOS switch K321, one end of another termination MOS switch K322 of MOS switch K321,
And pass through capacitance C323 and be grounded；The control terminal of the output termination MOS switch K322 of phase inverter U313, MOS switch K322's is another
The input terminal of isolation buffer amplifier U331 is terminated, and passes through capacitance C324 and is grounded；
The output terminal of isolation buffer amplifier U331 connects the anti-of hysteresis comparator U334 by positive voltage bias V332 respectively
Xiang Duan connects the in-phase end of hysteresis comparator U335 by negative voltage bias V333；The in-phase end of hysteresis comparator U334 connects error
The output signal Comp of amplifier U223；The output signal of the reverse phase termination error amplifier U223 of hysteresis comparator U335
Comp；The output terminal of hysteresis comparator U334, U335 connect two input terminals of nor gate U336 respectively；The output of nor gate U336
Meet the reset terminal of counter U337, the clock termination power tube switching signal On of counter U337；The output terminal of counter U337
Export the lowest point locking enable signal LockEn.
Further, the lowest point locking enable signal LockEn also controls of input hysteresis comparator U334, U335 respectively
End, when LockEn signals is high level, to increase the sluggish section of hysteresis comparator U334, U335.
Further, locking module U228 in the lowest point includes：D type flip flop U411, counter U415, counter U416, number
Comparator U417, selector U418 and nor gate U412, U413, NOT gate U414；
The output signal PWM of d type flip flop U411 clocks termination nor gate U227；The lowest point locking enable signal LockEn difference
Connect the reset terminal of d type flip flop U411 and the reset terminal of counter U415；The D termination high level of d type flip flop U411；
The Q output of d type flip flop U411 connects an input terminal of nor gate U412 and the selection control terminal of selector U418；
D type flip flop U411'sAn input terminal of output termination nor gate U413；Another input terminal of nor gate U412 and U413
Meet the output signal QR of NOT gate U243；The clock end of the output termination counter U415 of nor gate U412, nor gate U413's is defeated
Go out to terminate the clock end of counter U146；Power tube switching signal On connects the input terminal of NOT gate U414, the output terminal of NOT gate U414
Connect the reset terminal of counter U416；The output terminal of counter U415 and U416 connect two inputs of digital comparator U417 respectively
End；The output terminal of digital comparator U417 and the output signal PWM of nor gate U227 connect two inputs of selector U418 respectively
End；The output terminal output power pipe conducting trigger signal ONset of selector U148.
A kind of adaptive the lowest point lock-in circuit of Quasi-resonant switching power supply, including：
Input rectifying filter circuit, above-mentioned Switching Power Supply control unit, transformer T206, output rectifier and filter,
Export feedback circuit, power tube N1, primary current sampling resistor Rcs；
The positive output termination transformer T206 primary side winding different names end of input rectifying filter circuit, negative output termination primary side
Ground；
The current input terminal of transformer T206 primary side windings termination power tube N1 of the same name, the current output terminal of power tube N1 connect
Primary current sampling resistor Rcs one end, another termination primary sides of primary current sampling resistor Rcs；
In-phase input end connection primary current sampling resistor Rcs one end of peak point current comparator U230；Driving circuit
The switch control terminal of the output termination power tube N1 of U231；
The vice-side winding of transformer T206 connects output rectifier and filter, and direct current is exported by output rectifier and filter
Pressure；
Export the output feedback auxiliary winding that feedback circuit includes transformer T206, the both ends connection of output feedback auxiliary winding
Resistance R1, R2 of series connection；Auxiliary winding partial pressure feedback signal is obtained from series resistance R1, R2 tie point；Auxiliary winding partial pressure is anti-
Feedback signal connects the in-phase input end of the input terminal of sampling and keep module U221, quasi-resonance the lowest point comparator U242.
The advantage of the invention is that：The present invention obtains average resonance the lowest point number by integral process, as with reference to next
It prejudges and next Cyclical power pipe is controlled to be connected, so as to avoid causing due to switching frequency variation is excessive caused by sampling error
The abnormal sound problem that transformer is generated by vibration.
Description of the drawings
Fig. 1 is the adaptive valley conduction schematic diagram of quasi-resonance of the present invention.
Fig. 2 is the adaptive the lowest point lock-in circuit schematic diagram of Quasi-resonant switching power supply of the present invention.
Fig. 3 is the enabled inside modules schematic diagram of the lowest point locking of the present invention.
Fig. 4 is schematic diagram inside the lowest point locking module of the present invention.
Specific embodiment
With reference to specific drawings and examples, the invention will be further described.
The present invention provides a kind of adaptive the lowest point lock-in circuit of Quasi-resonant switching power supply, as shown in Fig. 2, including：
Input rectifying filter circuit, Switching Power Supply control unit 220, transformer T206, output rectifier and filter 207,
Export feedback circuit 208, power tube N1, primary current sampling resistor Rcs；
Wherein, Switching Power Supply control unit 220 is the core of the present invention, including：Sampling and keep module U221, error amplification
Device U223, saw-toothed wave generator U224, PWM comparator U225, quasi-resonance the lowest point comparator U242, NOT gate U243, nor gate
U227, the enabled module U229 of the lowest point locking, the lowest point locking module U228, switch latch U232, driving circuit U231, peak value electricity
Flow comparator U230；Wherein the conducting of power tube N1 is controlled by the output signal of the lowest point locking module U228, the pass of power tube N1
The disconnected output signal by peak point current comparator U230 controls；
Input rectifying filter circuit includes the bridge rectifier that diode D201~D204 is formed, filter capacitor C205；
The positive output termination transformer T206 primary side winding different names end of input rectifying filter circuit, negative output termination primary side；
The current input terminal of transformer T206 primary side windings termination power tube N1 of the same name, the current output terminal of power tube N1 connect
Primary current sampling resistor Rcs one end, another termination primary sides of primary current sampling resistor Rcs；NMOS can be used in power tube N1
Pipe, drain electrode, source electrode are respectively as current input terminal and current output terminal, and grid is as switch control terminal；
The vice-side winding of transformer T206 connects output rectifier and filter 207, is exported by output rectifier and filter 207
DC voltage；Output rectifier and filter 207 can include rectifier diode, filter capacitor, output resistance etc., this part is existing
There is the custom circuit of technology, repeat no more；
Export the output feedback auxiliary winding that feedback circuit 208 includes transformer T206, output feedback auxiliary winding both ends
Connect resistance R1, R2 of series connection；Auxiliary winding partial pressure feedback signal 110 is obtained from series resistance R1, R2 tie point；
The input terminal of sampling and keep module U221, the in-phase input end of quasi-resonance the lowest point comparator U242 connect respectively auxiliary around
Component presses feedback signal 110；The inverting input of the output termination error amplifier U223 of sampling and keep module U221, error are put
The in-phase input end reference voltage signal V of big device U223th_FB；The output signal Comp of error amplifier U223 connects PWM comparators
The inverting input of U225, the output of saw-toothed wave generator U224 connect the in-phase input end of PWM comparators U225；PWM comparators
An input terminal of the output termination nor gate U227 of U225；
The anti-phase input termination the lowest point discrimination standard signal V of quasi-resonance the lowest point comparator U242th_DEM；Quasi-resonance the lowest point ratio
Another input terminal of output termination nor gate U227 and the input terminal of NOT gate U243 compared with device U242；Nor gate U227's is defeated
Go out, the output signal QR of NOT gate U243 inputs the lowest point locking module U228 respectively；
Error amplifier output signal Comp and power tube switching signal On inputs the enabled module U229 of the lowest point locking respectively,
The lowest point locking enable signal LockEn inputs the lowest point locking module U228 that locking enabled module U229 in the lowest point is generated；Power tube is opened
OFF signal On inputs the lowest point locking module U228；The power tube conducting trigger signal of the lowest point locking module U228 output terminals output
The S ends of ONset input switch latch U232；It is rest-set flip-flop to switch latch U232, and the R of switch latch U232 terminates peak
It is worth the output terminal of current comparator U230；The in-phase input end connection primary current sampling resistor of peak point current comparator U230
Rcs one end, anti-phase input termination peak point current reference signal Vth_CS；
The Q ends output power pipe switching signal On of latch U232 is switched, power tube is added to by driving circuit U231
The switch control terminal of N1；
Fig. 1 is the adaptive valley conduction schematic diagram of quasi-resonance.Auxiliary winding divides feedback signal 110 after over-sampling is kept
An input signal as error amplifier U223；The output signal 120 of saw-toothed wave generator is as PWM comparators U225's
One input signal, the output signal Comp of error amplifier as another input signal of PWM comparators U225, work as letter
After numbers 120 intersect with signal Comp, PWM comparator U225 output signals are lower to form signal 141 from height, and signal 141 and standard are humorous
It shakes after the combination of output signal 150 of the lowest point comparator U242, trigger signal ONset is connected for forming power tube.
When signal ONset is by low increase, sawtooth signal 120 is immediately returned to original state and prepares to generate next week
The sawtooth signal of phase, the output signal of PWM comparators U225 invert, shape at once also with the variation of sawtooth signal 120
The burst pulse negative into one, as shown in the signal 141 in Fig. 1.
When the sampling of feedback signal FB, that is, auxiliary winding partial pressure feedback signal 110 is there are during deviation, which also will
It is amplified by error amplifier U223, the output valve of error amplifier U223 is caused to deviate, such as signal 131 and signal in Fig. 1
Shown in 133, this can lead to the variation of PWM comparator U225 output signals position, as shown in signal 142,143 in Fig. 1, and cause
The offset of power tube open signal, as shown in signal 162 and signal 163.And power tube open signal when being normal of signal 161.
111 correspondence system switching frequency average value of signal, when resonance the lowest point open signal 112 and 113 is relative to signal 111
When changing bigger, represent that the frequency of Switching Power Supply changes greatly, this is easy to cause the abnormal sound problem generated by oscillating transformers.
The present invention filters out the amplifier error caused by sampling error by being integrated to the output of error amplifier
Component, acquires error amplifier output average value, which corresponds to switching frequency average value.It is put down in the output of error amplifier
Positive and negative two offsets are superimposed in mean value and form voltage window, is compared with the output instantaneous flow of error amplifier, works as error
The output instantaneous flow of amplifier falls in the range of above-mentioned voltage window and continuously keeps several switch periods, and system starts to start paddy
Bottom locking mode simultaneously increases above-mentioned voltage window range, avoids leading to the lowest point locking unlock due to false triggering.Work as error amplifier
Output instantaneous flow be more than above-mentioned increased voltage window range, the lowest point locking unlock, system restarts the lowest point and locked
Journey.
By the primary side winding of transformer T206 and the coil coupled relation of auxiliary winding, in transformer demagnetization phase, from
Auxiliary winding coil is sampled to obtain auxiliary winding partial pressure feedback signal 110 and be kept；Sampling keeps signal as error amplifier
The negative-feedback input of U223, sampling keep signal and reference voltage signal Vth_FBAfter error amplifier U223 amplifications, output
Error signal realizes loop adjustment automatically, and when output error signal increases, expression output loading aggravates, and works as output error signal
It is lower, represents that output loading lightens.
The output signal Comp of error amplifier U223 is compared with the sawtooth signal that saw-toothed wave generator generates is by PWM
Device U225 is modulated, and is generated pwm signal and is input to the lowest point locking module U228；Quasi-resonance the lowest point comparator is by comparing auxiliary
Winding divides feedback signal 110 and the lowest point discrimination standard signal Vth_DEM, export resonance the lowest point signal, as the lowest point locking module
Another input；
Locking enabled module U229 in the lowest point is filtered out by being integrated to the output of error amplifier U223 because of sampling error
Caused by amplifier error output component, acquire the output average value of error amplifier.In the output of error amplifier U223
Positive and negative two offsets are superimposed on average value and form voltage window, are compared with the output instantaneous flow of error amplifier U223,
When the output instantaneous flow of error amplifier U223 is fallen in the range of above-mentioned voltage window and continuously keeps several switch periods, the lowest point
The enabled module output the lowest point of locking latches enable signal LockEn and increases above-mentioned voltage window range, as error amplifier U223
Output instantaneous flow be more than increased above-mentioned voltage window range, the lowest point locking unlock, system restarts the lowest point and locked
Journey.
The lowest point locking module U228 latches the resonance the lowest point number average corresponding to error amplifier output integration amount, makees
For one of digital comparator with reference to comparison signal, output with another the lowest point real-time counter (following counter U416) into
Row compares, which can reset counts again, when the counting week of another the lowest point real-time counter
When phase reaches the lowest point number average being latched, digital comparator will export next period conducting trigger signal, accurate at this time humorous
The adaptive the lowest point of Switching Power Supply of shaking is locked.
The output signal setting switch latch U232 of the lowest point locking module U228, the conducting of control power tube N1, this is opened
The reset signal for shutting storage U232 is the output of peak point current comparator U230, and power tube N1 is turned off after reset.
Peak point current comparator U230 is by comparing the pressure drop of power pipe end sampling resistor Rcs and peak current threshold voltage
Size, output high level signal carry out reset switch latch U232, control the shutdown of power tube.
Below to the specific course of work of the present invention and the enabled module U229 of the lowest point locking, the lowest point locking module U228
Realization be described in detail；
Enter off-phases after power tube N1 is connected, transformer T206 enters demagnetization process, sampling and keep module
U221 sampling auxiliary winding partial pressure feedback signals 110 simultaneously preserve, and as an input signal of error amplifier U223, error is put
Another input signal of big device U223 is reference voltage signal Vth_FB；Sampling keeps signal and reference voltage signal Vth_FB's
For difference after error amplifier U223 amplifications, output signal Comp is connected to an input terminal of PWM comparators U225；
Another input signal of PWM comparators U225 is to connect the output of saw-toothed wave generator U224；With error amplifier
The output signal Comp of U223 is compared, and exports one of switch control signal；
Another switch control signal is generated by quasi-resonance the lowest point comparator U242, and the one of quasi-resonance the lowest point comparator U242
A input termination auxiliary winding partial pressure feedback signal 110, another input termination the lowest point discrimination standard signal Vth_DEM.Quasi-resonance
Synchronizing signal of the output signal of the lowest point comparator U242 as power tube valley conduction, the output with PWM comparators U225 are believed
Number by nor gate U227 combine after be input to the lowest point locking module U228.
Locking enabled module U229 in the lowest point calculates switching frequency average value in real time, is obtained when switching frequency mean value calculation
When error is less than setting range, locking enabled module U229 outputs the lowest point locking enable signal in the lowest point controls the lowest point locking module
U228 enters frequency lock procedure；
After locking enabled module U229 in the lowest point sends out the lowest point locking enable signal, the lowest point locking module 228 is first calculated and is protected
The resonance the lowest point periodicity corresponding to switching frequency average value is deposited, digital comparator is connected to as resonance the lowest point number average
One input terminal.Another input termination the lowest point real-time counter of digital comparator, the lowest point real-time counter is at each
It can all be counted again in switch periods, when power tube is connected, the lowest point real-time counter automatic clear, humorous after demagnetization
It is started counting up during shaking.When the lowest point, real-time counter count value reaches resonance the lowest point number average, digital comparator will
High level signal is exported to trigger the conducting of power tube.
Before the lowest point locks, the conducting trigger signal of power tube N1 is by the output of PWM comparators U225 and quasi-resonance paddy
Bottom comparator U242 output combination controls.
The cut-off signals of power tube N1 are generated by peak point current comparator U230；After power tube N1 conductings, primary side inductance
Into excited state, inductive current is continuously increased, when pressure drop of the inductive current on sampling resistor Rcs is more than peak point current benchmark
Signal Vth_CSWhen, peak point current comparator U230 output high level, switch register U232 is reset, power tube N1 shutdowns.
The electric principle of the enabled module U229 of the lowest point locking is referring to Fig. 3；Including：MOS switch K321, K322, phase inverter U313,
Capacitance C323, C324, isolation buffer amplifier U331, positive voltage bias V332, negative voltage bias V333, hysteresis comparator
U334, U335, nor gate U336, counter U337；
Power tube switching signal On connects the control terminal of MOS switch K321 and the input terminal of phase inverter U313；Error amplifier
The output signal Comp of U223 connects one end of MOS switch K321, one end of another termination MOS switch K322 of MOS switch K321,
And pass through capacitance C323 and be grounded；The control terminal of the output termination MOS switch K322 of phase inverter U313, MOS switch K322's is another
The input terminal of isolation buffer amplifier U331 is terminated, and passes through capacitance C324 and is grounded；
The output terminal of isolation buffer amplifier U331 connects the anti-of hysteresis comparator U334 by positive voltage bias V332 respectively
Xiang Duan connects the in-phase end of hysteresis comparator U335 by negative voltage bias V333；The in-phase end of hysteresis comparator U334 connects error
The output signal Comp of amplifier U223；The output signal of the reverse phase termination error amplifier U223 of hysteresis comparator U335
Comp；The output terminal of hysteresis comparator U334, U335 connect two input terminals of nor gate U336 respectively；The output of nor gate U336
Meet the reset terminal of counter U337, the clock termination power tube switching signal On of counter U337；The output terminal of counter U337
Export the lowest point locking enable signal LockEn；
More preferably, locking enable signal LockEn in the lowest point also inputs the control terminal of hysteresis comparator U334, U335 respectively, with
When LockEn signals are high level, increase the sluggish section of hysteresis comparator U334, U335；
Signal Comp is the output of error amplifier U223, and signal On is the signal for controlling power tube switch, phase inverter
U313, MOS switch K321, K322 and capacitance C323 and C324 constitute low frequency integrating circuit.Each switching process, error
The output signal Comp of amplifier U223 transmits primary, the frequency characteristic of low frequency integrating circuit to capacitance C324 by capacitance C323
Proportionate relationship depending on switching frequency and capacitance C323 and capacitance C324.After system switching is stablized, the voltage on capacitance C324
The as average value of the output signal Comp of error amplifier U223.
Isolation buffer amplifier U331 and positive voltage bias V332, negative voltage bias V333 are formed centered on integral voltage
Voltage window, the reference voltage as hysteresis comparator U334 and U335.Another of hysteresis comparator U334 and U335 are defeated
Enter the output signal Comp that signal is error amplifier.When the signal Comp of error amplifier is fallen centered on integral voltage
In the range of voltage window, nor gate U336 exports a high level signal, and counter U337 starts to calculate, if nor gate U336
High level is exported in continuous 32 switch periods, the LockEn signals of counter U337 outputs are high level signal, indicate the lowest point
Locking module U228 works.
When LockEn signals are high level, increase the sluggish section of hysteresis comparator U334, U335, to increase integration electricity
Voltage window range centered on pressure prevents false triggering and leads to the lowest point locking unlock.
The electric principle of the lowest point locking module U228 participates in Fig. 4, including：D type flip flop U411, counter U415, counter
U416, digital comparator U417, selector U418 and nor gate U412, U413, NOT gate U414；
The output signal PWM of d type flip flop U411 clocks termination nor gate U227；The lowest point locking enable signal LockEn difference
Connect the reset terminal of d type flip flop U411 and the reset terminal of counter U415；The D termination high level of d type flip flop U411；
The Q output of d type flip flop U411 connects an input terminal of nor gate U412 and the selection control terminal of selector U418；
D type flip flop U411'sAn input terminal of output termination nor gate U413；Another input terminal of nor gate U412 and U413
Meet the output signal QR of NOT gate U243；The clock end of the output termination counter U415 of nor gate U412, nor gate U413's is defeated
Go out to terminate the clock end of counter U146；Power tube switching signal On connects the input terminal of NOT gate U414, the output terminal of NOT gate U414
Connect the reset terminal of counter U416；The output terminal of counter U415 and U416 connect two inputs of digital comparator U417 respectively
End；The output terminal of digital comparator U417 and the output signal PWM of nor gate U227 connect two inputs of selector U418 respectively
End；The output terminal output power pipe conducting trigger signal ONset of selector U148；
When signal LockEn is low level, counter U415 has been at cleared condition, and d type flip flop U411 is reset.
After signal LockEn is increased, counter U415 is started counting up, in signal PWM by the low rising edge increased, D triggerings
The output signal 425 of device U411 becomes high level, and counter U415 stops counting and preserving count value, the counting of counter U415
It is worth a comparison reference 427 as digital comparator U417.
When power tube switching signal On is high level, counter U416 is reset；When power tube switching signal On is low electricity
Usually, and after the output signal of d type flip flop U411 425 becomes high level, counter U416 is started counting up, and counter U416's is defeated
Go out another fiducial value 428 as digital comparator U417.When fiducial value 428 is equal to 427, digital comparator U417 outputs
High level.
The output signal of selector U418 is selected by 425 low and high level of signal, when signal 425 be low level when or
The output signal PWM of NOT gate U227 is output to signal ONset, when signal 425 is high level, the output of digital comparator U417
Signal 429 is output to signal ONset.
Merely exemplary, the present invention has been applied to flyback power supply converter.It will be appreciated that the present invention has more
It is widely applied range.
It should be noted last that more than specific embodiment is merely illustrative of the technical solution of the present invention and unrestricted,
Although the present invention is described in detail with reference to example, it will be understood by those of ordinary skill in the art that, it can be to the present invention
Technical solution be modified or replaced equivalently, without departing from the spirit and scope of technical solution of the present invention, should all cover
In scope of the presently claimed invention.
Claims (5)
1. a kind of Switching Power Supply control unit, which is characterized in that including：
Sampling and keep module U221, error amplifier U223, saw-toothed wave generator U224, PWM comparator U225, quasi-resonance the lowest point
Comparator U242, NOT gate U243, nor gate U227, the enabled module U229 of the lowest point locking, the lowest point locking module U228, switch latch
Device U232, driving circuit U231, peak point current comparator U230；
The input terminal of sampling and keep module U221, the in-phase input end of quasi-resonance the lowest point comparator U242 for connect respectively auxiliary around
Component pressure feedback signal (110)；The inverting input of the output termination error amplifier U223 of sampling and keep module U221, error
The in-phase input end reference voltage signal V of amplifier U223th_FB；The output signal Comp of error amplifier U223 meets PWM and compares
The inverting input of device U225, the output of saw-toothed wave generator U224 connect the in-phase input end of PWM comparators U225；PWM compares
An input terminal of the output termination nor gate U227 of device U225；
The anti-phase input termination the lowest point discrimination standard signal V of quasi-resonance the lowest point comparator U242th_DEM；Quasi-resonance the lowest point comparator
Another input terminal of output termination nor gate U227 of U242 and the input terminal of NOT gate U243；Nor gate U227's exports, is non-
The output signal QR of door U243 inputs the lowest point locking module U228 respectively；
Error amplifier output signal Comp and power tube switching signal On inputs the enabled module U229 of the lowest point locking, the lowest point respectively
The lowest point locking enable signal LockEn inputs the lowest point locking module U228 that the enabled module U229 of locking is generated；Power tube switch letter
Number On input the lowest point locking module U228；The power tube conducting trigger signal ONset of the lowest point locking module U228 output terminals output
The S ends of input switch latch U232；It is rest-set flip-flop to switch latch U232, and the R termination peak values of switch latch U232 are electric
Flow the output terminal of comparator U230；The in-phase input end of peak point current comparator U230 is used to connect primary current sampling resistor
Rcs one end, anti-phase input termination peak point current reference signal Vth_CS；
Switch the Q ends output power pipe switching signal On, power tube switching signal On input driving circuits U231 of latch U232
Input terminal, the output terminal of driving circuit U231 is used to connect the switch control terminal of power tube N1.
2. Switching Power Supply control unit as described in claim 1, which is characterized in that
Locking enabled module U229 in the lowest point includes：MOS switch K321, K322, phase inverter U313, capacitance C323, C324, isolation are slow
Rush amplifier U331, positive voltage bias V332, negative voltage bias V333, hysteresis comparator U334, U335, nor gate U336, meter
Number device U337；
Power tube switching signal On connects the control terminal of MOS switch K321 and the input terminal of phase inverter U313；Error amplifier U223
Output signal Comp connect one end of MOS switch K321, one end of another termination MOS switch K322 of MOS switch K321, and lead to
Cross capacitance C323 ground connection；The control terminal of the output termination MOS switch K322 of phase inverter U313, another termination of MOS switch K322
The input terminal of isolation buffer amplifier U331, and pass through capacitance C324 and be grounded；
The output terminal of isolation buffer amplifier U331 connects the reverse side of hysteresis comparator U334 by positive voltage bias V332 respectively,
The in-phase end of hysteresis comparator U335 is connect by negative voltage bias V333；The in-phase end of hysteresis comparator U334 connects error amplifier
The output signal Comp of U223；The output signal Comp of the reverse phase termination error amplifier U223 of hysteresis comparator U335；It is sluggish
The output terminal of comparator U334, U335 connect two input terminals of nor gate U336 respectively；The output of nor gate U336 connects counter
The reset terminal of U337, the clock termination power tube switching signal On of counter U337；The output terminal output the lowest point of counter U337
Lock enable signal LockEn.
3. Switching Power Supply control unit as claimed in claim 2, which is characterized in that
The lowest point locking enable signal LockEn also inputs the control terminal of hysteresis comparator U334, U335 respectively, to work as LockEn letters
When number being high level, increase the sluggish section of hysteresis comparator U334, U335.
4. Switching Power Supply control unit as described in claim 1, which is characterized in that
The lowest point locking module U228 includes：D type flip flop U411, counter U415, counter U416, digital comparator U417, choosing
Select device U418 and nor gate U412, U413, NOT gate U414；
The output signal PWM of d type flip flop U411 clocks termination nor gate U227；The lowest point locking enable signal LockEn meets D respectively
The reset terminal of trigger U411 and the reset terminal of counter U415；The D termination high level of d type flip flop U411；
The Q output of d type flip flop U411 connects an input terminal of nor gate U412 and the selection control terminal of selector U418；D is touched
The Q output of hair device U411 connects an input terminal of nor gate U413；Another input termination of nor gate U412 and U413 are non-
The output signal QR of door U243；The clock end of the output termination counter U415 of nor gate U412, the output terminal of nor gate U413
Connect the clock end of counter U146；Power tube switching signal On connects the input terminal of NOT gate U414, the output termination meter of NOT gate U414
The reset terminal of number device U416；The output terminal of counter U415 and U416 connect two input terminals of digital comparator U417 respectively；Number
The output terminal of word comparator U417 and the output signal PWM of nor gate U227 connect two input terminals of selector U418 respectively；Choosing
Select the output terminal output power pipe conducting trigger signal ONset of device U148.
5. a kind of adaptive the lowest point lock-in circuit of Quasi-resonant switching power supply, including：
Input rectifying filter circuit, Switching Power Supply control unit such as according to any one of claims 1 to 4, transformer T206,
Output rectifier and filter (207), output feedback circuit (208), power tube N1, primary current sampling resistor Rcs；
The positive output termination transformer T206 primary side winding different names end of input rectifying filter circuit, negative output termination primary side；
The current input terminal of transformer T206 primary side windings termination power tube N1 of the same name, the current output terminal of power tube N1 connect primary
Current sampling resistor Rcs one end, another termination primary sides of primary current sampling resistor Rcs；
In-phase input end connection primary current sampling resistor Rcs one end of peak point current comparator U230；Driving circuit U231's
The switch control terminal of output termination power tube N1；
The vice-side winding of transformer T206 connects output rectifier and filter (207), is exported by output rectifier and filter (207)
DC voltage；
Output feedback auxiliary winding of the feedback circuit (208) including transformer T206 is exported, output feedback auxiliary winding both ends connect
Meet resistance R1, R2 of series connection；Auxiliary winding partial pressure feedback signal (110) is obtained from series resistance R1, R2 tie point；Auxiliary winding
Partial pressure feedback signal (110) connects the in-phase input end of the input terminal of sampling and keep module U221, quasi-resonance the lowest point comparator U242.
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| CN201810128823.0A CN108173435B (en) | 2018-02-08 | 2018-02-08 | Switch power supply control unit and quasi-resonant switch power supply self-adaptive valley locking circuit |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111565048A (en) * | 2020-06-15 | 2020-08-21 | 深圳职业技术学院 | Successive approximation type ADC logic control system |
| CN111884494A (en) * | 2020-07-23 | 2020-11-03 | 成都启臣微电子股份有限公司 | Quasi-resonance valley bottom conduction circuit with compensation function |
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| CN112701924A (en) * | 2020-12-28 | 2021-04-23 | 昂宝电子（上海）有限公司 | Apparatus and method for valley lock in quasi-resonant switching power supplies |
| CN114649958A (en) * | 2022-05-20 | 2022-06-21 | 深圳英集芯科技股份有限公司 | Switching power supply and charger |
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Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110216559A1 (en) * | 2010-03-05 | 2011-09-08 | Hong Kong Applied Science & Technology Research Institute Company Limited | Constant-Current Control Module using Inverter Filter Multiplier for Off-line Current-Mode Primary-Side Sense Isolated Flyback Converter |
| US20110305053A1 (en) * | 2010-06-11 | 2011-12-15 | System General Corporation | Switching Control Circuits with Valley Lock for Power Converters |
| CN202231629U (en) * | 2011-09-16 | 2012-05-23 | 惠州市纳伟仕视听科技有限公司 | Power adapter of all-in-one computer |
| CN102594154A (en) * | 2011-03-09 | 2012-07-18 | 崇贸科技股份有限公司 | Switching controller for power converter |
| CN103490636A (en) * | 2012-06-11 | 2014-01-01 | 比亚迪股份有限公司 | Quasi-resonant control method, quasi-resonant system and quasi-resonant device for switching power supplies |
| JP2014146946A (en) * | 2013-01-29 | 2014-08-14 | Ricoh Co Ltd | Peak hold circuit, bottom hold circuit, midpoint generation circuit, data slicer circuit, amplitude detection circuit and radio communication device |
| US20160241150A1 (en) * | 2015-02-17 | 2016-08-18 | Fairchild (Taiwan) Corporation | Alternating valley switching for power converter |
| CN106533214A (en) * | 2016-12-21 | 2017-03-22 | 无锡硅动力微电子股份有限公司 | Switching power supply converter control circuit and control method thereof |
| CN206498339U (en) * | 2017-03-09 | 2017-09-15 | 南京邮电大学 | A kind of primary side feedback AC DC converters of super-low standby power consumption |
| CN107231096A (en) * | 2017-07-14 | 2017-10-03 | 无锡硅动力微电子股份有限公司 | The multistage loop control circuit of primary side feedback Switching Power Supply |
| CN207910684U (en) * | 2018-02-08 | 2018-09-25 | 无锡硅动力微电子股份有限公司 | Switching Power Supply control unit and the adaptive the lowest point lock-in circuit of Quasi-resonant switching power supply |
-
2018
- 2018-02-08 CN CN201810128823.0A patent/CN108173435B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110216559A1 (en) * | 2010-03-05 | 2011-09-08 | Hong Kong Applied Science & Technology Research Institute Company Limited | Constant-Current Control Module using Inverter Filter Multiplier for Off-line Current-Mode Primary-Side Sense Isolated Flyback Converter |
| US20110305053A1 (en) * | 2010-06-11 | 2011-12-15 | System General Corporation | Switching Control Circuits with Valley Lock for Power Converters |
| CN102594154A (en) * | 2011-03-09 | 2012-07-18 | 崇贸科技股份有限公司 | Switching controller for power converter |
| CN202231629U (en) * | 2011-09-16 | 2012-05-23 | 惠州市纳伟仕视听科技有限公司 | Power adapter of all-in-one computer |
| CN103490636A (en) * | 2012-06-11 | 2014-01-01 | 比亚迪股份有限公司 | Quasi-resonant control method, quasi-resonant system and quasi-resonant device for switching power supplies |
| JP2014146946A (en) * | 2013-01-29 | 2014-08-14 | Ricoh Co Ltd | Peak hold circuit, bottom hold circuit, midpoint generation circuit, data slicer circuit, amplitude detection circuit and radio communication device |
| US20160241150A1 (en) * | 2015-02-17 | 2016-08-18 | Fairchild (Taiwan) Corporation | Alternating valley switching for power converter |
| CN106533214A (en) * | 2016-12-21 | 2017-03-22 | 无锡硅动力微电子股份有限公司 | Switching power supply converter control circuit and control method thereof |
| CN206498339U (en) * | 2017-03-09 | 2017-09-15 | 南京邮电大学 | A kind of primary side feedback AC DC converters of super-low standby power consumption |
| CN107231096A (en) * | 2017-07-14 | 2017-10-03 | 无锡硅动力微电子股份有限公司 | The multistage loop control circuit of primary side feedback Switching Power Supply |
| CN207910684U (en) * | 2018-02-08 | 2018-09-25 | 无锡硅动力微电子股份有限公司 | Switching Power Supply control unit and the adaptive the lowest point lock-in circuit of Quasi-resonant switching power supply |
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111565048B (en) * | 2020-06-15 | 2023-05-12 | 深圳职业技术学院 | Logic control system of successive approximation type ADC |
| CN111565048A (en) * | 2020-06-15 | 2020-08-21 | 深圳职业技术学院 | Successive approximation type ADC logic control system |
| CN111884494A (en) * | 2020-07-23 | 2020-11-03 | 成都启臣微电子股份有限公司 | Quasi-resonance valley bottom conduction circuit with compensation function |
| CN111884494B (en) * | 2020-07-23 | 2021-11-12 | 成都启臣微电子股份有限公司 | Quasi-resonance valley bottom conduction circuit with compensation function |
| CN112332647A (en) * | 2020-11-11 | 2021-02-05 | 深圳市富满电子集团股份有限公司 | Valley bottom locking circuit based on quasi-resonance control technology, chip and power supply |
| CN112701924A (en) * | 2020-12-28 | 2021-04-23 | 昂宝电子（上海）有限公司 | Apparatus and method for valley lock in quasi-resonant switching power supplies |
| US11901813B2 (en) | 2020-12-28 | 2024-02-13 | On-Bright Electronics (Shanghai) Co., Ltd. | Systems and methods for valley locking related to quasi-resonant switching power supplies |
| CN114649958B (en) * | 2022-05-20 | 2022-07-29 | 深圳英集芯科技股份有限公司 | Switching power supply and charger |
| WO2023221812A1 (en) * | 2022-05-20 | 2023-11-23 | 深圳英集芯科技股份有限公司 | Switch power source and charger |
| CN114649958A (en) * | 2022-05-20 | 2022-06-21 | 深圳英集芯科技股份有限公司 | Switching power supply and charger |
| CN115065254A (en) * | 2022-08-19 | 2022-09-16 | 深圳英集芯科技股份有限公司 | Control device and method of flyback switching power supply and charger |
| CN116388552A (en) * | 2023-06-07 | 2023-07-04 | 梵塔半导体技术(杭州)有限公司 | Switching circuit control method, control chip and switching circuit |
| CN116388552B (en) * | 2023-06-07 | 2023-09-19 | 梵塔半导体技术(杭州)有限公司 | Switching circuit control method, control chip and switching circuit |
| CN117458889A (en) * | 2023-12-22 | 2024-01-26 | 无锡硅动力微电子股份有限公司 | Flyback switching power supply control circuit |
| CN117458889B (en) * | 2023-12-22 | 2024-03-22 | 无锡硅动力微电子股份有限公司 | Flyback switching power supply control circuit |
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