CN206525000U - Adaptive line voltage compensation LED drive circuit based on primary side feedback - Google Patents
Adaptive line voltage compensation LED drive circuit based on primary side feedback Download PDFInfo
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- CN206525000U CN206525000U CN201720109869.9U CN201720109869U CN206525000U CN 206525000 U CN206525000 U CN 206525000U CN 201720109869 U CN201720109869 U CN 201720109869U CN 206525000 U CN206525000 U CN 206525000U
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
- Y02B20/30—Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]
Abstract
The utility model discloses a kind of adaptive line voltage compensation LED drive circuit based on primary side feedback, including AC power, rectifier bridge, LC wave filters, primary absorbent circuit, the transformer being made up of armature winding, secondary windings and assists winding, secondary circuit, auxiliary power supply circuit, power switch pipe, power switch pipe current sampling resistor, compensating electric capacity and LED drive control circuits；LED drive controls circuit includes triangular-wave generator, compressor, VZCDDetector, first comparator, the second comparator, logic controller, gate driving circuit, trigger, constant current regulator, sampling hold circuit, voltage follower, peak point current prediction device, operational amplifier, except 2 circuits and VREFGenerator.LED drive circuit of the present utility model is based on primary side feedback and inverse-excitation type is controlled, high efficiency and the driving of high power factor LED constant current can be realized, the peak primary currents deviation that can be produced to system transmission delay carries out adaptive equalization, can realize the input voltage line regulation less than 1.5% in full voltage range.
Description
Technical field
The utility model is related to a kind of LED drive circuit based on primary side feedback, more particularly to a kind of based on primary side feedback
Adaptive line voltage compensation LED drive circuit.
Background technology
Under the background that global energy shortage, environmental requirement are improved constantly, green energy conservation photograph is greatly developed in countries in the world
It is bright.LED illumination is developed rapidly as a kind of revolutionary energy-saving illumination technology.
Because LED is the sensitive semiconductor devices of characteristic, there is negative temperature characteristic again, thus need in application process pair
It carries out steady-working state and protection, so as to generate the concept of driving.Requirement of the LED component to driving power supply is near severe
Carve, LED can be directly connected to 220V electric main unlike common incandescent lamp bulb.LED is 2~3 volts of low voltage drive,
The complicated translation circuit of design is had to, the LED of different purposes will be equipped with different power supply adaptors.It is right on international market
The efficiency conversion of LED drive power, effective power, constant current accuracy, power source life, electromagnetic compatibility requirement it is all very high.Efficiently
Rate, High Power Factor, security isolation, to meet EMI standards, high current control accuracy, high reliability, small volume, cost low just
Crucial standard diagrams as LED drive power.Further, since fluctuation and the difference of various countries' line voltage of line voltage, LED
Driving power supply must also have preferable input voltage line regulation.
The AC/DC control technologies of primary side feedback are the new A C/DC control technologies grown up for nearest 10 years, and traditional
Secondary side feedback structure is compared, and is eliminated two chips and a constituent element device of matched work, is saved on system board
Space, reduces cost and improves the reliability of system.LED drive etc. have to volume requirement very high market it is wide
Application prospect.
The existing inverse-excitation type LED drive circuit based on primary side feedback as shown in figure 1, including：AC power, LC filtering
Device, primary absorbent circuit, the transformer being made up of armature winding, secondary windings and assists winding, secondary circuit, auxiliary power supply electricity
Road, power switch pipe M1, power switch pipe current sampling resistor R4, compensating electric capacity C5 and LED drive control circuit.LED drives
Control circuit includes：Triangular-wave generator, compressor, VZCDDetector, comparator, logic controller, gate driving circuit, touch
Send out device, constant current regulator, sampling hold circuit, voltage follower, operational amplifier and VREFGenerator.
The circuit is using fixed ON time control model, that is power switch pipe M1 ON time is constant.
Derive that load LED average current is formula below according to correlation theory：
Wherein, ILEDFor load LED average currents, n is the turn ratio of transformer master secondary winding, VmFor primary voltage, Lm
For primary electrical sensibility reciprocal, TONFor the ON time of power switch pipe, Toff(t) it is the deadline of power switch pipe, Ts(t) it is work(
The switch periods of rate switching tube, ωLFor the angular frequency of input ac voltage.
System passes through constant TON, so as to realize that constant current drives, while such control mode can also realize High Power Factor.
But it is due to the presence of transmission delay caused by system control logic and power switch, so during the closing of power switch pipe reality
Between point to be later than preferable shut-in time point.As shown in Fig. 2 it can be seen that transmission delay Td, the actually detected primary arrived
Peak point current is higher than preferable peak primary currents.So under different input voltages, the slope of the rising of peak point current
It is different, TdAlso it is different.This results in Δ ipkAlso it can become with input voltage, which results in the input voltage line of system
Property characteristic can be deteriorated.
Utility model content
Utility model goal of the invention：For problem above, the utility model proposes a kind of based on the adaptive of primary side feedback
Line voltage compensation LED drive circuit.
Technical scheme：To realize the purpose of this utility model, the technical scheme that the utility model is used is：One kind is based on
The adaptive line voltage compensation LED drive circuit of primary side feedback, including AC power, rectifier bridge, LC wave filters, primary absorbent electricity
Road, the transformer being made up of armature winding, secondary windings and assists winding, secondary circuit, auxiliary power supply circuit, power switch
Pipe, power switch pipe current sampling resistor, compensating electric capacity and LED drive control circuits；LED drive controls circuit includes triangular wave
Generator, compressor, VZCDDetector, first comparator, the second comparator, logic controller, gate driving circuit, trigger,
Constant current regulator, sampling hold circuit, voltage follower, peak point current prediction device, operational amplifier, except 2 circuits and VREFOccur
Device.
AC power is sequentially connected the armature winding of rectifier bridge, LC wave filters, primary absorbent circuit and transformer, transformer
Secondary windings connection secondary circuit, transformer assists winding connection auxiliary power supply circuit, the grid and LED of power switch pipe
The GATE ports connection of drive control circuit, the drain electrode of power switch pipe and the armature winding of transformer are connected, power switch pipe
Source electrode be connected with the CS ports of LED drive control circuits, and be grounded by power switch pipe current sampling resistor, compensating electric capacity
One end be connected with the COMP ports of LED drive control circuits, the other end ground connection, the DEMAG ports of LED drive control circuits
Connect the voltage signal of transformer assists winding.
The DEMAG ports connection V of LED drive control circuitsZCDDetector, VZCDDetector is also associated with compressor, VZCD
The output end connection logic controller of detector, reconnects gate driving circuit, gate driving circuit connects output end GATE,
For driving power switching tube；The CS ports connection voltage follower of LED drive control circuits, the output with logic controller is believed
Number pass through sampling hold circuit jointly, then input constant current regulator；Operational amplifier include electrode input end, negative input and
Output end, the electrode input end connection V of operational amplifierREFGenerator, the negative input connection constant current adjustment of operational amplifier
The output end of device, the output end of operational amplifier connects the COMP ports of LED drive control circuits；First comparator includes positive pole
Input, negative input and output end, the electrode input end connection triangular-wave generator of first comparator, first comparator
The output end of negative input concatenation operation amplifier, trigger is rest-set flip-flop, and R ends connect the output end of first comparator, S
End connection compressor, Q ends connect the input of logic controller；The output signal of operational amplifier, which is passed through, removes 2 circuits, reconnects
The negative input of second comparator, the output signal of triangular-wave generator connects the electrode input end of the second comparator, second
The output signal of comparator sequentially passes through logic controller and sampling hold circuit, and the output signal of sampling hold circuit is input to
Peak point current prediction device, then input constant current regulator.
Beneficial effect：Adaptive line voltage compensation LED drive circuit of the present utility model is the flyback based on primary side feedback
Formula controls framework, realizes that the LED of high efficiency and high power factor is permanent in the case of meeting input ac power and load isolation
Stream driving, the circuit can be realized adaptively to be mended to the deviation for producing peak primary currents due to system transmission delay
Repay, the input voltage line regulation less than 1.5% in full voltage range can be realized.
Brief description of the drawings
Fig. 1 is the existing inverse-excitation type LED drive circuit schematic diagram based on primary side feedback；
Fig. 2 is the peak primary currents schematic diagram of existing LED drive circuit；
Fig. 3 is the adaptive line voltage compensation LED drive circuit of the present utility model based on primary side feedback；
Fig. 4 is adaptive line voltage compensation LED drive circuit operating diagram of the present utility model.
Embodiment
The technical solution of the utility model is further described with reference to the accompanying drawings and examples.
It is the adaptive line voltage compensation LED drive circuit described in the utility model based on primary side feedback as shown in Figure 3,
Including：AC power 1, rectifier bridge 2, LC wave filters 3, primary absorbent circuit 4, by armature winding, secondary windings and assists winding
The transformer 5 of composition, secondary circuit 6, auxiliary power supply circuit 7, power switch pipe M1, power switch pipe current sampling resistor R4,
Compensating electric capacity C5 and LED drive control circuit 8.
AC power 1 is sequentially connected the armature winding of rectifier bridge 2, LC wave filters 3, primary absorbent circuit 4 and transformer 5,
The secondary windings connection secondary circuit 6 of transformer 5, assists winding connection auxiliary power supply circuit 7.Power switch pipe M1 grid
It is connected with the GATE ports of LED drive control circuits, power switch pipe M1 drain electrode is connected with armature winding, power switch pipe M1
Source electrode be connected with the CS ports of LED drive control circuits, and pass through power switch pipe current sampling resistor R4 ground connection.Compensation electricity
Hold C5 one end to be connected with the COMP ports of LED drive control circuits, other end ground connection.
The alternating voltage of input is converted into output by the full-bridge bridge that rectifier bridge 2 is made up of four diodes, realization
DC voltage, including the first diode D1, the second diode D2, the 3rd diode D3 and the 4th diode D4.LC wave filters 3
Including the first inductance L1 and the first electric capacity C1, the DC voltage that rectification circuit is obtained is filtered.Primary absorbent circuit 4 includes
First resistor R1, the second electric capacity C2 and the 5th diode D5, primary parallel connection RCD absorbing circuits, for suppressing overvoltage,
Absorb leakage inductance surge voltage.Secondary circuit 6 includes the 3rd electric capacity C3 and the 6th diode D6, the connection load of the 3rd electric capacity C3 two ends
LED, for powering load.
Auxiliary power supply circuit 7 includes second resistance R2,3rd resistor R3, the 7th diode D7 and the 4th electric capacity C4, the 3rd
Resistance R3 and the 4th electric capacity C4 ground connection, second resistance R2 and 3rd resistor R3 formation partial pressures, the sampling of LED drive controls circuit 8 the
Voltage on three resistance R3, and connect the DEMAG ports of LED drive control circuits.
The information changed in load LED lamp is detected by the voltage change for the assists winding of transformer 5 of accurately sampling.Work as work(
When rate switching tube is opened, the primary winding current i of transformer 5pFrom 0 linear rise to ipk.Now energy stores are in armature winding,
After power switch pipe is turned off, energy is delivered to secondary windings by transformer 5, and is sent to output end by rectifying and wave-filtering.
During this, the forward voltage of output voltage and diode is reflected to assists winding, and in degaussing end time point, secondary windings is defeated
Going out voltage and assists winding has linear relationship, if the voltage of the assists winding of sampling now, and formed by accurate loop
Feedback, it is possible to regulated output voltage.
LED drive controls circuit 8, including：Triangular-wave generator, compressor, VZCDDetector, first comparator, the second ratio
Compared with device, logic controller, gate driving circuit, trigger, constant current regulator, sampling hold circuit, voltage follower, peak value electricity
Flow prediction device, operational amplifier, except 2 circuits and VREFGenerator.The input DEMAG of LED drive control circuits is auxiliary for sampling
The voltage signal of winding is helped, the input CS of LED drive control circuits is used for sampled power switching tube current sampling resistor
Voltage signal on R4, the output end GATE of LED drive control circuits is used for driving power switching tube M1.
The voltage signal of LED drive control circuit input ends DEMAG assists winding, by VZCDDetector, VZCD
Detector is connected with compressor, then is input to logic controller, then to gate driving circuit, gate driving circuit connection output end
GATE, for driving power switching tube M1.On LED drive control circuit input ends CS power switch pipe current sampling resistor R4
Voltage signal, by voltage follower, pass through sampling hold circuit with the output signal of logic controller, then input constant current tune
Whole device.Operational amplifier includes electrode input end, negative input and output end, and the electrode input end of operational amplifier is connected
VREFGenerator, the negative input of operational amplifier connects the output end of constant current regulator, the output end connection of operational amplifier
Compensating electric capacity C5.First comparator includes electrode input end, negative input and output end, the electrode input end of first comparator
Connect triangular-wave generator, the output end of the negative input concatenation operation amplifier of first comparator.Trigger triggers for RS
Device, R ends connect the output end of first comparator, S ends connection compressor, the input of Q ends connection logic controller.
LED drive control circuits are also added into peak point current prediction device, except 2 circuits and the second comparator, and sampling keeps electricity
The output signal on road passes through peak point current prediction device, then inputs constant current regulator.The output signal V of operational amplifierCOMPBy
Except 2 circuits, signal V is obtainedHALF, the output signal V with triangular-wave generatorRAMPIt is compared by the second comparator, signal
VHALFConnect the negative input of the second comparator, signal VRAMPThe electrode input end of the second comparator is connected, the second obtained ratio
Output signal compared with device passes through logic controller and sampling hold circuit.The output signal of sampling hold circuit is input to peak value electricity
Prediction device is flowed, peak point current prediction device is calculated, then inputs constant current regulator.Opened the light pipe T in poweronDuring/2 conducting, in advance
Estimate out Δ ipk, to due to system transmission delay TdCaused peak primary currents error is compensated.
Specific works mode is as shown in figure 4, t1=Ton/ 2, Td=t2-t1, pass through adaptive line voltage compensation circuit, system
In TonDuring/2 conducting, peak primary currents error delta ipk is estimated out in advance, and compensate so that power switch pipe is in ideal
ipkClosed during value.The present invention opens the light pipe by adding peak point current prediction device in systems, except 2 circuits and comparator in power
TonDuring/2 conducting, sampling peak primary currents estimate Δ ipk, finally realize to producing primary peak due to system transmission delay
The deviation for being worth electric current carries out adaptive equalization, and the circuit can realize the input voltage less than 1.5% in system full voltage range
Line regulation.
Claims (7)
1. a kind of adaptive line voltage compensation LED drive circuit based on primary side feedback, it is characterised in that：Including AC power
(1), rectifier bridge (2), LC wave filters (3), primary absorbent circuit (4), be made up of armature winding, secondary windings and assists winding
Transformer (5), secondary circuit (6), auxiliary power supply circuit (7), power switch pipe (M1), power switch pipe current sampling resistor
(R4), compensating electric capacity (C5) and LED drive controls circuit (8)；
Wherein, LED drive controls circuit (8) includes triangular-wave generator, compressor, VZCDDetector, first comparator, second
Comparator, logic controller, gate driving circuit, trigger, constant current regulator, sampling hold circuit, voltage follower, peak value
Electric current prediction device, operational amplifier, except 2 circuits and VREFGenerator；
Wherein, AC power (1) is sequentially connected rectifier bridge (2), LC wave filters (3), primary absorbent circuit (4) and transformer (5)
Armature winding, transformer (5) secondary windings connection secondary circuit (6), transformer (5) assists winding connection auxiliary power supply
Circuit (7), the grid of power switch pipe (M1) is connected with the GATE ports of LED drive controls circuit (8), power switch pipe (M1)
Drain electrode be connected with the armature winding of transformer (5), the source electrode of power switch pipe (M1) and the CS of LED drive controls circuit (8)
Port is connected, and is grounded by power switch pipe current sampling resistor (R4), one end and the LED drive controls of compensating electric capacity (C5)
The COMP ports connection of circuit (8), other end ground connection, the DEMAG ports connection transformer (5) of LED drive controls circuit (8) is auxiliary
Help the voltage signal of winding.
2. the adaptive line voltage compensation LED drive circuit according to claim 1 based on primary side feedback, its feature exists
In：The DEMAG ports connection V of LED drive controls circuit (8)ZCDDetector, VZCDDetector is also associated with compressor, VZCDDetection
The output end connection logic controller of device, reconnects gate driving circuit, gate driving circuit connection output end GATE, for driving
Dynamic power switch pipe (M1)；
The CS ports connection voltage follower of LED drive controls circuit (8), the output signal with logic controller is jointly by adopting
Sample holding circuit, then input constant current regulator；
Operational amplifier includes electrode input end, negative input and output end, the electrode input end connection V of operational amplifierREF
Generator, the negative input of operational amplifier connects the output end of constant current regulator, the output end connection LED of operational amplifier
The COMP ports of drive control circuit (8)；
First comparator includes electrode input end, negative input and output end, the electrode input end connection three of first comparator
Angle wave producer, the output end of the negative input concatenation operation amplifier of first comparator, trigger is rest-set flip-flop, R ends
Connect the output end of first comparator, S ends connection compressor, the input of Q ends connection logic controller；
The output signal of operational amplifier, which is passed through, removes 2 circuits, reconnects the negative input of the second comparator, triangular-wave generator
Output signal connect the electrode input end of the second comparator, the output signal of the second comparator sequentially pass through logic controller and
Sampling hold circuit, the output signal of sampling hold circuit is input to peak point current prediction device, then inputs constant current regulator.
3. the adaptive line voltage compensation LED drive circuit according to claim 1 based on primary side feedback, its feature exists
In：Rectifier bridge (2) includes the first diode (D1), the second diode (D2), the 3rd diode (D3) and the 4th diode (D4).
4. the adaptive line voltage compensation LED drive circuit according to claim 1 based on primary side feedback, its feature exists
In：LC wave filters (3) include the first inductance (L1) and the first electric capacity (C1).
5. the adaptive line voltage compensation LED drive circuit according to claim 1 based on primary side feedback, its feature exists
In：Primary absorbent circuit (4) includes first resistor (R1), the second electric capacity (C2) and the 5th diode (D5).
6. the adaptive line voltage compensation LED drive circuit according to claim 1 based on primary side feedback, its feature exists
In：Secondary circuit (6) includes the 3rd electric capacity (C3) and the 6th diode (D6), the two ends connection load LED of the 3rd electric capacity (C3).
7. the adaptive line voltage compensation LED drive circuit according to claim 1 based on primary side feedback, its feature exists
In：Auxiliary power supply circuit (7) includes second resistance (R2), 3rd resistor (R3), the 7th diode (D7) and the 4th electric capacity (C4),
Voltage in 3rd resistor (R3) and the 4th electric capacity (C4) ground connection, LED drive controls circuit (8) sampling 3rd resistor (R3), and
Connect the DEMAG ports of LED drive controls circuit (8).
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720109869.9U CN206525000U (en) | 2017-02-06 | 2017-02-06 | Adaptive line voltage compensation LED drive circuit based on primary side feedback |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201720109869.9U CN206525000U (en) | 2017-02-06 | 2017-02-06 | Adaptive line voltage compensation LED drive circuit based on primary side feedback |
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| CN206525000U true CN206525000U (en) | 2017-09-26 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106793339A (en) * | 2017-02-06 | 2017-05-31 | 苏州智浦芯联电子科技股份有限公司 | Self adaptation line voltage compensation LED drive circuit based on primary side feedback |
| CN114205945A (en) * | 2021-11-24 | 2022-03-18 | 广东新昇电业科技股份有限公司 | Four-in-one dimming circuit adopting primary side feedback and constant voltage |
-
2017
- 2017-02-06 CN CN201720109869.9U patent/CN206525000U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106793339A (en) * | 2017-02-06 | 2017-05-31 | 苏州智浦芯联电子科技股份有限公司 | Self adaptation line voltage compensation LED drive circuit based on primary side feedback |
| CN106793339B (en) * | 2017-02-06 | 2018-11-30 | 苏州智浦芯联电子科技股份有限公司 | Adaptive line voltage compensation LED drive circuit based on primary side feedback |
| CN114205945A (en) * | 2021-11-24 | 2022-03-18 | 广东新昇电业科技股份有限公司 | Four-in-one dimming circuit adopting primary side feedback and constant voltage |
| CN114205945B (en) * | 2021-11-24 | 2022-10-11 | 广东新昇电业科技股份有限公司 | Four-in-one dimming circuit adopting primary side feedback and constant voltage |
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