CN105025636B - LED light adjusting circuits - Google Patents
LED light adjusting circuits Download PDFInfo
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- CN105025636B CN105025636B CN201510468409.0A CN201510468409A CN105025636B CN 105025636 B CN105025636 B CN 105025636B CN 201510468409 A CN201510468409 A CN 201510468409A CN 105025636 B CN105025636 B CN 105025636B
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Abstract
The invention discloses a kind of LED light adjusting circuits, including dim signal generation circuit, dim signal change-over circuit, pwm control circuit and LED drive circuit；The dim signal generation circuit is used to produce dim signal；The dim signal change-over circuit is used for the dim signal for receiving neutral signal and dim signal generation circuit output, and produces the first square-wave signal and the second square-wave signal according to the neutral signal and the dim signal；The pwm control circuit is used for according to first square-wave signal and second square-wave signal, adjusts the dutycycle of pwm signal and is output to the LED drive circuit；The LED drive circuit is used to drive the LED to light according to the pwm signal.LED illumination lamp brightness is controlled using single live wire mode, without remote control, without control line, without laying power line again, it is possible to achieve the replacement upgrading of general lighting lamp, cost is low, and jamproof ability is strong.
Description
Technical field
The present invention relates to LED technology field, more particularly to a kind of LED light adjusting circuits.
Background technology
LED because its operating voltage, electric current must be controlled strictly with meet its working characteristics and it is reliable, efficient require,
So general LED is required for being equipped with special driving power.And user also have on different opportunitys to light illumination it is different
Demand；As we need light fixture to be worked with high-high brightness to meet our needs to illumination sometimes, otherwise we are then sometimes
Brightness can be reduced to meet our requirements to weaker light filling by needing it, while also save the consumption of electric energy.So LED is adjusted
Photocontrol is while user's greater demand is met also to preventing global warming from making contributions；Again because user will to LED light modulation
Ask：With excellent linear, broad dimming scope (brightness 0-100% regulations), higher stability, high efficiency, high power
Factor, low EMI, it is realized with a low cost, therefore the drivings of the LED with excellent dimming characteristic just seem more important.
Traditional LED light modulations are adjusted dimming control signal by higher frequency using the control light modulation of two line power line carriers
Make, transmitted after isolated variable by power supply zero, fiery two lines, the signal needed is then taken out in terminal；Utilize the light modulation control of taking-up
Signal processed controls LED or gas discharge lamp current to reach the purpose of light modulation.The method advantage is mainly：Dim good linearity,
Scope is wide up to 0~100%, and electromagnetic interference is small, and line power factor can be made very high, and reliability is higher.Shortcoming is mainly：
There is particular/special requirement to subscribers' line, its light modulator palpus zero fiery two-wire power supplies of 220V, and carrier signal need to be via zero fiery two lines superposition
Transmission, has particular/special requirement to subscribers' line, is made troubles to user, and adds holistic cost, limits it and promotes the use of.
The content of the invention
The embodiment of the present invention proposes a kind of LED light adjusting circuits, and it is linear not that it can effectively solve existing light adjusting circuit light modulation
It is good, uniformity is poor, inefficient, low power factor, high expensive, can not match with original subscribers' line, have to new subscribers' line
The problems such as particular/special requirement.
The embodiment of the present invention provides a kind of LED light adjusting circuits, including dim signal generation circuit, dim signal conversion electricity
Road, pwm control circuit and LED drive circuit；
The dim signal generation circuit include power switch, the first diode, the second diode, the first dimmer switch with
Second dimmer switch, and there is live wire signal input part and dim signal output end；The first end of the power switch is connected to
The live wire signal input part；The anode of first diode is connected to described after being coupled with the negative electrode of second diode
Second end of power switch；The negative electrode of first diode passes through first dimmer switch and the dim signal output end
Connection；The anode of second diode is connected by second dimmer switch with the dim signal output end；Described
One dimmer switch switchs with second dimmer switch for dynamic circuit breaker；
The dim signal change-over circuit is used for the tune for receiving neutral signal and dim signal generation circuit output
Optical signal, and the first square-wave signal and the second square-wave signal are produced according to the neutral signal and the dim signal；
The pwm control circuit is used to, according to first square-wave signal and second square-wave signal, adjust pwm signal
Dutycycle and be output to the LED drive circuit；Wherein, the pwm control circuit is detecting first square-wave signal
When having lacked a square wave, one grade of dutycycle of the pwm signal is improved, or detecting that second square-wave signal lacks
When having lacked a square wave, one grade of dutycycle of the pwm signal is reduced；
The LED drive circuit is used to drive the LED to light according to the pwm signal.
In one embodiment, the dim signal change-over circuit includes first resistor, second resistance, the first optocoupler, the
Two optocouplers, 3rd resistor, the 4th resistance, the 5th resistance, the 6th resistance, the 7th resistance, the 8th resistance, the first electric capacity, the second electricity
Appearance, the first phase inverter and the second phase inverter；The first end of the first resistor is used to receive the dim signal；Described first
Second end of resistance is connected with the first input end of first optocoupler, and is connected with the second input of second optocoupler；
The first end of the second resistance is used to receive neutral signal；Second end of the second resistance and the first of second optocoupler
Input connects, and is connected with the second input of first optocoupler；
First output end of first optocoupler connects DC voltage by the 3rd resistor, and the of first optocoupler
Two output ends pass through the 4th resistance eutral grounding；The first end of 5th resistance connects with the second output end of first optocoupler
Connect, the second end of the 5th resistance is connected with the input of first phase inverter, and passes through first capacity earth；Institute
The output end for stating the first phase inverter exports first square-wave signal；
First output end of second optocoupler connects DC voltage by the 6th resistance, and the of second optocoupler
Two output ends pass through the 7th resistance eutral grounding；The first end of 8th resistance connects with the second output end of second optocoupler
Connect, the second end of the 8th resistance is connected with the input of second phase inverter, and passes through second capacity earth；Institute
The output end for stating the second phase inverter exports second square-wave signal.
In another embodiment, the dim signal change-over circuit includes the first low pass active filter circuit, the first RC
Filter circuit, first voltage follow circuit, the first bleeder circuit, the first comparison circuit, the second low pass active filter circuit, second
RC filter circuits, second voltage follow circuit, the second bleeder circuit and the second comparison circuit；
The input of the first low pass active filter circuit is used to receive the dim signal, and first low pass is active
The output end of filter circuit passes sequentially through the first RC filter circuits and first voltage follows circuit to be connected to first ratio
Compared with the first input end of circuit；The first input end of first comparison circuit is connected to described by first bleeder circuit
Second input of the second comparison circuit；The output end of first comparison circuit exports first square-wave signal；
The input of the second low pass active filter circuit is used to receive the neutral signal, and second low pass is active
The output end of filter circuit passes sequentially through the 2nd RC filter circuits and second voltage follows circuit to be connected to second ratio
Compared with the first input end of circuit；The first input end of second comparison circuit is connected to described by second bleeder circuit
Second input of the first comparison circuit；The output end of second comparison circuit exports second square-wave signal.
Further, the first low pass active filter circuit includes first resistor, second resistance, the first electric capacity, first
Operational amplifier and 3rd resistor；The first end of the first resistor be the first low pass active circuit input, institute
The second end for stating first resistor is grounded by the second resistance；First electric capacity is in parallel with the second resistance；Described
Second end of one resistance is connected with the normal phase input end of first operational amplifier；The both ends of the 3rd resistor connect respectively
The inverting input and output end of first operational amplifier；The output end of first operational amplifier is described first
The output end of low pass active filter circuit；
The second low pass active filter circuit includes the 4th resistance, the 5th resistance, the second electric capacity, the second operational amplifier
And the 6th resistance；The first end of 4th resistance be the second low pass active circuit input, the 4th resistance
The second end pass through the 5th resistance eutral grounding；Second electric capacity and the 5th resistor coupled in parallel；The of 4th resistance
Two ends are connected with the normal phase input end of second operational amplifier；The both ends of 6th resistance connect second fortune respectively
Calculate the inverting input and output end of amplifier；The output end of second operational amplifier is the active filter of the second low pass
The output end of wave circuit.
Further, the first RC filter circuits include the 7th resistance and the 3rd electric capacity；The first of 7th resistance
End is connected with the output end of the first low pass active filter circuit, and the second end of the 7th resistance passes through the 3rd electric capacity
Ground connection；The output end of 7th resistance is the output end of the first RC filter circuits；
The 2nd RC filter circuits include the 8th resistance and the 4th electric capacity；The first end of 8th resistance and described the
The output end connection of two low pass active filter circuits, the second end of the 8th resistance passes through the 4th capacity earth；It is described
The output end of 8th resistance is the output end of the 2nd RC filter circuits.
Further, the first voltage follows circuit to include the 3rd operational amplifier and the 9th resistance；Described 3rd
The normal phase input end of operational amplifier follows the input of circuit, the output of the 3rd operational amplifier for the first voltage
The output end that circuit is followed for the first voltage is held, the both ends of the 9th resistance connect the 3rd operational amplifier respectively
Inverting input and output end；
The second voltage follows circuit to include four-operational amplifier and the tenth resistance；The four-operational amplifier
Normal phase input end follow the input of circuit for the second voltage, the output end of the four-operational amplifier is described the
The output end of two voltage follower circuits, the both ends of the tenth resistance connect the anti-phase input of the four-operational amplifier respectively
End and output end.
Further, first bleeder circuit includes the 11st resistance and the 12nd resistance；11st resistance
First end is the input of first bleeder circuit, and the second end of the 11st resistance is the defeated of first bleeder circuit
Go out end；Second end of the 11st resistance passes through the 12nd resistance eutral grounding；
Second bleeder circuit includes the 13rd resistance and the 14th resistance；The first end of 13rd resistance is institute
The input of the second bleeder circuit is stated, the second end of the 13rd resistance is the output end of second bleeder circuit；It is described
Second end of the 13rd resistance passes through the 14th resistance eutral grounding.
Further, first comparison circuit includes the 5th operational amplifier and the 15th resistance；5th computing
The inverting input of amplifier is the first input end of first comparison circuit, and the positive of the 5th operational amplifier inputs
Hold as the second input of first comparison circuit, the output end of the 5th operational amplifier is first comparison circuit
Output end, the both ends of the 15th resistance connect the normal phase input end and output end of the 3rd operational amplifier respectively；
Second comparison circuit includes the 6th operational amplifier and the 16th resistance；6th operational amplifier it is anti-
Phase input is the first input end of second comparison circuit, and the normal phase input end of the 6th operational amplifier is described the
Second input of two comparison circuits, the output end of the 6th operational amplifier are the output end of second comparison circuit,
The both ends of 16th resistance connect the normal phase input end and output end of the 6th operational amplifier respectively.
In one embodiment, the LED drive circuit includes the 18th resistance, the 19th resistance, the first triode, the
20 resistance；The first end of 18th resistance is the input of the LED drive circuit；The second of 18th resistance
End is connected with the base stage of first triode, and passes through the 19th resistance eutral grounding；The emitter stage of first triode
Ground connection；The output end of the extremely described LED drive circuit of current collection of first triode, passes through the 20th resistance and direct current
Voltage connects.
In another embodiment, the LED drive circuit includes the 21st resistance, the second triode, the 22nd
Resistance, the 23rd resistance, the 24th resistance, the 6th electric capacity, the 3rd triode, the 4th triode and the 3rd diode；
The first end of 21st resistance is the input of the LED drive circuit, and the second end of the 21st resistance connects
It is connected to the base stage of second triode；The grounded emitter of second triode, colelctor electrode and the 22nd resistance
First end, the connection of the first end of the first end of the 23rd resistance and the 24th resistance；Described 20th
The second end ground connection of two resistance；Second end of the 23rd resistance and the base stage of the 3rd triode, the described 4th 3
The base stage connection of pole pipe, and pass through the 6th capacity earth；Second end of the 24th resistance is connected with DC voltage；
The positive pole of 3rd diode is connected with DC voltage, and negative pole is connected with the colelctor electrode of the 4th triode；Described 4th
The emitter stage of triode is connected with the emitter stage of the 3rd triode, the output end as the LED drive circuit；Described
The grounded collector of three triodes；The opposite polarity of 3rd triode and the 4th triode.
Brief description of the drawings
Fig. 1 is the structured flowchart of LED light adjusting circuits provided by the invention；
Fig. 2 is the circuit diagram of the dim signal generation circuit in Fig. 1；
Fig. 3 is the circuit diagram of the dim signal change-over circuit in one embodiment；
Fig. 4 is the structured flowchart of the dim signal change-over circuit in another embodiment；
Fig. 5 is the circuit diagram of the dim signal change-over circuit in Fig. 4；
Fig. 6 is the circuit diagram of the LED drive circuit in one embodiment；
Fig. 7 is the circuit diagram of the LED drive circuit in another embodiment.
Embodiment
Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clear, complete
Site preparation describes, it is clear that described embodiment is only part of the embodiment of the present invention, rather than whole embodiments.It is based on
Embodiment in the present invention, those of ordinary skill in the art are obtained every other under the premise of creative work is not made
Embodiment, belong to the scope of protection of the invention.
It is the structured flowchart of LED light adjusting circuits provided in an embodiment of the present invention referring to Fig. 1, it includes dim signal generation
Circuit 1, dim signal change-over circuit 2, pwm control circuit 3 and LED drive circuit 4.
The dim signal generation circuit 1 has live wire signal input part L and dim signal output end Lout；The light modulation
Signaling conversion circuit 2 have dim signal input, neutral signal input N, the first square wave signal output part Pulse+ and
Second square wave signal output part Pulse-；The pwm control circuit 3 has the first square wave signal input part, the second square-wave signal
Input and pwm signal output end；The LED drive circuit 4 has pwm signal input and driving signal output end；Institute
Live wire signal input part L is stated to be used to be connected with live wire；The dim signal output end Lout connects with the dim signal input
Connect；The neutral signal input N is used to be connected with zero line；The first square wave signal output part Pulse+ and the first party
Ripple signal input part connects；The second square wave signal output part Pulse- is connected with the second square wave signal input part；Institute
Pwm signal output end is stated to be connected with the pwm signal input；The driving signal output end is used to drive LED to light.
Referring to Fig. 2, it is the circuit diagram of the dim signal generation circuit 1 in Fig. 1.The dim signal generation circuit 1 wraps
Power switch S1, the first diode D1, the second diode D2, the first dimmer switch S2 and the second dimmer switch S3 are included, and is had
Live wire signal input part L and dim signal output end Lout；The first end of the power switch S1 is connected to the live wire signal
Input L；The anode of the first diode D1 is connected to the power supply after being coupled with the negative electrode of the second diode D2 and opened
Close S1 the second end；The negative electrode of the first diode D1 passes through the first dimmer switch S2 and the dim signal output end
Lout connections；The anode of the second diode D2 passes through the second dimmer switch S3 and the dim signal output end Lout
Connection；The first dimmer switch S2 and the second dimmer switch S3 switchs for dynamic circuit breaker.
Wherein, switches of the power switch S1 as the dim signal generation circuit 1, live wire signal (believe by sine wave
Number) the power switch S1 closure after be input to the dim signal generation circuit 1.
In normal operating conditions, power switch S1, the first dimmer switch S2 and the second dimmer switch S3 are closures
, the positive half-wave of live wire signal is output to dim signal by the first diode D1 and the first dimmer switch S2 and exported
Lout is held, the negative half-wave of live wire signal is output to dim signal by the second diode D2 and the second dimmer switch S3
Output end Lout, therefore now the dim signal is also sine wave.
When the first dimmer switch S2 disconnects, the positive half-wave of live wire signal can not be output to the dim signal output end
Lout, therefore now the dim signal only has the waveform of negative half-wave, i.e. positive half-wave is cut away, and the number that positive half-wave is cut away takes
The time certainly disconnected in the first dimmer switch S2.
When the second dimmer switch S3 disconnects, the negative half-wave of live wire signal can not be output to the dim signal output end
Lout, therefore now the dim signal only has the waveform of positive half-wave, i.e., negative half-wave is cut away, and the number that negative half-wave is cut away takes
The time certainly disconnected in the second dimmer switch S3.
As it is highly preferred that the dim signal generation circuit 1 also includes the 17th resistance R17 and the 5th electric capacity C5；Institute
The 17th resistance R17 and the 5th electric capacity C5 series circuits in series are stated, the both ends of the series circuit connect institute respectively
State power switch S1 the second end and the dim signal output end Lout.17th resistance and the 5th electric capacity C5
For by target signal filter more than power frequency, reducing signal interference.
The dim signal change-over circuit 2 be used for receive neutral signal and the dim signal generation circuit 1 output
Dim signal, and the first square-wave signal and the second square-wave signal are produced according to the neutral signal and the dim signal.
As shown in figure 3, it is the circuit diagram of the dim signal change-over circuit in one embodiment.
The dim signal change-over circuit includes first resistor R1, second resistance R2, the first optocoupler OC1, the second optocoupler
OC2,3rd resistor R3, the 4th resistance R4, the 5th resistance R5, the 6th resistance R6, the 7th resistance R7, the 8th resistance R8, the first electricity
Hold C1, the second electric capacity C2, the first phase inverter T1 and the second phase inverter T2；The first end of the first resistor R1 is used to receive institute
State dim signal；The second end of the first resistor R1 is connected with the first input end of the first optocoupler OC1, and with described
Two optocoupler OC2 the second input connection；The first end of the second resistance R2 is used to receive neutral signal；The second resistance
R2 the second end is connected with the first input end of the second optocoupler OC2, and is connected with the second input of the first optocoupler OC1
Connect；
The first output end of the first optocoupler OC1 passes through the 3rd resistor R3 connections DC voltage, first light
Coupling OC1 the second output end is grounded by the 4th resistance R4；The first end of the 5th resistance R5 and first optocoupler
OC1 the second output end connection, the second end of the 5th resistance R5 is connected with the input of the first phase inverter T1, and is led to
Cross the first electric capacity C1 ground connection；The output end of the first phase inverter T1 exports first square-wave signal；
The first output end of the second optocoupler OC2 passes through the 6th resistance R6 connection DC voltages, second light
Coupling OC2 the second output end is grounded by the 7th resistance R7；The first end of the 8th resistance R8 and second optocoupler
OC2 the second output end connection, the second end of the 8th resistance R8 is connected with the input of the second phase inverter T2, and is led to
Cross the second electric capacity C2 ground connection；The output end of the second phase inverter T2 exports second square-wave signal.
In the present embodiment, light-coupled isolation is realized by the first optocoupler OC1 and the second optocoupler OC2, when dim signal is in
During positive half-wave, the first optocoupler OC1 conductings, the second optocoupler OC2 cut-offs, the first phase inverter T1 output high level, the second phase inverter T2
Export low level；When dim signal is in negative half-wave, the second optocoupler OC2 conductings, the first optocoupler OC1 cut-offs, the first phase inverter
T1 outputs are low level, and the second phase inverter T2 exports high level.That is the first phase inverter T1 and the second phase inverter T2 export 0- respectively
5V square wave, frequency are about 50Hz, and half period is about differed on the time.When cutting away the positive half-wave of AC signal, described
One phase inverter T1 exports low level, and the square wave of the second phase inverter T2 outputs 0-5V, frequency is about 50Hz.Similarly, when cutting away
During the negative half-wave of AC signal, the second phase inverter T2 exports low level, and the first phase inverter T1 exports 0-5V square wave,
Frequency is about 50Hz.
Referring to Fig. 4, it is the structured flowchart of the dim signal change-over circuit in another embodiment.The light modulation letter
Number change-over circuit 2 include the first low pass active filter circuit 211, the first RC filter circuits 212, first voltage follow circuit 213,
First bleeder circuit 214, the first comparison circuit 215, the second low pass active filter circuit 221, the 2nd RC filter circuits 222,
Two voltage follower circuits 223, the second bleeder circuit 224 and the second comparison circuit 225；
The input of the first low pass active filter circuit 211 is used to receive the dim signal, first low pass
The output end of active filter circuit 211 passes sequentially through the first RC filter circuits 212 and first voltage follows circuit 213 to connect
To the first input end of first comparison circuit 215；The first input end of first comparison circuit 215 passes through described first
Bleeder circuit 214 is connected to the second input of second comparison circuit 225；The output end of first comparison circuit 215
Export first square-wave signal；
The input of the second low pass active filter circuit 221 is used to receive the neutral signal, second low pass
The output end of active filter circuit 221 passes sequentially through the 2nd RC filter circuits 222 and second voltage follows circuit 223 to connect
To the first input end of second comparison circuit 225；The first input end of second comparison circuit 225 passes through described second
Bleeder circuit 224 is connected to the second input of first comparison circuit 215；The output end of second comparison circuit 225
Export second square-wave signal.
Specifically, as shown in figure 5, it is the circuit diagram of the dim signal change-over circuit in Fig. 4.
The first low pass active filter circuit 211 includes first resistor R1, second resistance R2, the first electric capacity C1, first
Operational amplifier A 1 and 3rd resistor R3；The first end of the first resistor R1 is the input of the first low pass active circuit
End, the second end of the first resistor R1 is grounded by the second resistance R2；The first electric capacity C1 and the second resistance
R2 is in parallel；The second end of the first resistor R1 is connected with the normal phase input end of first operational amplifier A 1；Described 3rd
Resistance R3 both ends connect the inverting input and output end of first operational amplifier A 1 respectively；First computing is put
Big device A1 output end is the output end of the first low pass active filter circuit 211；
The second low pass active filter circuit 221 includes the 4th resistance R4, the 5th resistance R5, the second electric capacity C2, second
The resistance R6 of operational amplifier A 2 and the 6th；The first end of the 4th resistance R4 is the input of the second low pass active circuit
End, the second end of the 4th resistance R4 is grounded by the 5th resistance R5；The second electric capacity C2 and the 5th resistance
R5 is in parallel；The second end of the 4th resistance R4 is connected with the normal phase input end of second operational amplifier A 2；Described 6th
Resistance R6 both ends connect the inverting input and output end of second operational amplifier A 2 respectively；Second computing is put
Big device A2 output end is the output end of the second low pass active filter circuit 221.
The first RC filter circuits 212 include the 7th resistance R7 and the 3rd electric capacity C3；The first of the 7th resistance R7
End is connected with the output end of the first low pass active filter circuit 211, and the second end of the 7th resistance R7 passes through described the
Three electric capacity C3 are grounded；The output end of the 7th resistance R7 is the output end of the first RC filter circuits 212；
The 2nd RC filter circuits 222 include the 8th resistance R8 and the 4th electric capacity C4；The first of the 8th resistance R8
End is connected with the output end of the second low pass active filter circuit 221, and the second end of the 8th resistance R8 passes through described the
Four electric capacity C4 are grounded；The output end of the 8th resistance R8 is the output end of the 2nd RC filter circuits 222.
The first voltage follows circuit 213 to include the 3rd operational amplifier A 3 and the 9th resistance R9；3rd fortune
The normal phase input end for calculating amplifier A3 follows the input of circuit 213, the 3rd operational amplifier A 3 for the first voltage
Output end follow the output end of circuit 213 for the first voltage, the both ends of the 9th resistance R9 connect described the respectively
The inverting input and output end of three operational amplifier As 3；
The second voltage follows circuit 223 to include four-operational amplifier A4 and the tenth resistance R10；4th fortune
The normal phase input end for calculating amplifier A4 follows the input of circuit 223, the four-operational amplifier A4 for the second voltage
Output end follow the output end of circuit 223 for the second voltage, the both ends of the tenth resistance R10 connect described the respectively
Four-operational amplifier A4 inverting input and output end.
First bleeder circuit 214 includes the 11st resistance R11 and the 12nd resistance R12；The 11st resistance R11
First end be first bleeder circuit 214 input, the second end of the 11st resistance R11 is first partial pressure
The output end of circuit 214；The second end of the 11st resistance R11 is grounded by the 12nd resistance R12；
Second bleeder circuit 224 includes the 13rd resistance R13 and the 14th resistance R14；The 13rd resistance R13
First end be second bleeder circuit 224 input, the second end of the 13rd resistance R13 is second partial pressure
The output end of circuit 224；The second end of the 13rd resistance R13 is grounded by the 14th resistance R14.
First comparison circuit 215 includes the 5th operational amplifier A 5 and the 15th resistance R15；5th computing is put
Big device A5 inverting input is the first input end of first comparison circuit 215, and the 5th operational amplifier A 5 is just
Phase input is the second input of first comparison circuit 215, and the output end of the 5th operational amplifier A 5 is described
The output end of first comparison circuit 215, the both ends of the 15th resistance R15 connect the 3rd operational amplifier A 3 respectively
Normal phase input end and output end；
Second comparison circuit 225 includes the 6th operational amplifier A 6 and the 16th resistance R16；6th computing is put
Big device A6 inverting input is the first input end of second comparison circuit 225, and the 6th operational amplifier A 6 is just
Phase input is the second input of second comparison circuit 225, and the output end of the 6th operational amplifier A 6 is described
The output end of second comparison circuit 225, the both ends of the 16th resistance R16 connect the 6th operational amplifier A 6 respectively
Normal phase input end and output end.
Wherein, first low-pass active filter is used to filter the HFS of the dim signal of input, and described the
One RC filter circuits 212, which are used to filter half-wave, puts down；The input impedance of the first voltage follower is very high, and output impedance is very low,
Therefore buffer action can be played between prime and the input and output of rear class.Similarly, second low-pass active filter is used for
The HFS of the neutral signal of input is filtered, the 2nd RC filter circuits 222, which are used to filter half-wave, puts down；Second electricity
The input impedance of pressure follower is very high, and output impedance is very low, therefore isolation can be played between prime and the input and output of rear class
Effect.
By being compared to upper and lower 2 road signal voltage, when not carrying out copped wave to AC signal, the first comparison circuit
215 and second comparison circuit 225 export 0-5V square wave respectively, frequency is about 50Hz, and half period is about differed on the time.When
When cutting away the positive half-wave of AC signal, first comparison circuit 215 exports low level, and second comparison circuit 225 exports
0-5V square wave, frequency are about 50Hz.Similarly, when cutting away the negative half-wave of AC signal, second comparison circuit 225 exports
Low level, first comparison circuit 215 export 0-5V square wave, and frequency is about 50Hz.
The pwm control circuit 3 is used for according to first square-wave signal and second square-wave signal, adjustment PWM letters
Number dutycycle and be output to the LED drive circuit 4；Wherein, the pwm control circuit 3 is detecting first square wave
When signal has lacked a square wave, one grade of dutycycle of the pwm signal is improved, or detecting the second square wave letter
When number having lacked a square wave, one grade of dutycycle of the pwm signal is reduced.
In one embodiment, the pwm control circuit 3 includes model STM8S103F2P6 control chip, and described
19th pin of control chip is used to receive first square-wave signal, and the 20th pin of the control chip is used to receive described second
Square-wave signal, the 10th pin of the control chip are used to export the pwm signal.
As shown in fig. 6, it is the circuit diagram of the LED drive circuit in one embodiment.
The LED drive circuit 4 includes the 18th resistance R18, the 19th resistance R19, the first triode Q1, the 20th electricity
Hinder R20；The first end of the 18th resistance R18 is the input of the LED drive circuit 4；The 18th resistance R18's
Second end is connected with the base stage of the first triode Q1, and is grounded by the 19th resistance R19；First triode
Q1 grounded emitter；The output end of the extremely described LED drive circuit 4 of current collection of the first triode Q1, pass through described
20 resistance R20 are connected with DC voltage.Wherein, the first triode Q1 is used for the driving current for strengthening LED.
As shown in fig. 7, it is the circuit diagram of the LED drive circuit in another embodiment.
The LED drive circuit 4 includes the 21st resistance R21, the second triode Q2, the 22nd resistance R22, second
13 resistance R23, the 24th resistance R24, the 6th electric capacity C6, the 3rd triode Q3, the 4th triode Q4 and the three or two pole
Pipe D3；The first end of the 21st resistance R21 be the LED drive circuit 4 input, the 21st resistance
R21 the second end is connected to the base stage of the second triode Q2；The grounded emitter of the second triode Q2, colelctor electrode with
The first end of the 22nd resistance R22, the first end of the 23rd resistance R23 and the 24th resistance
R24 first end connection；The second end ground connection of the 22nd resistance R22；The second end of the 23rd resistance R23 with
The base stage of the 3rd triode Q3, the connection of the base stage of the 4th triode Q4, and be grounded by the 6th electric capacity C6；Institute
The second end for stating the 24th resistance R24 is connected with DC voltage；The positive pole of the 3rd diode D3 is connected with DC voltage,
Negative pole is connected with the colelctor electrode of the 4th triode Q4；The emitter stage of the 4th triode Q4 and the 3rd triode Q3
Emitter stage connection, the output end as the LED drive circuit；The grounded collector of the 3rd triode Q3；Described
Three triode Q3 and the 4th triode Q4 opposite polarity.Wherein, the second triode Q2 is used to strengthen driving force,
The output of its colelctor electrode is also pwm signal.The RC filtering that pwm signal forms by the 23rd resistance R23 and the 6th electric capacity C6
Circuit conversion is the maximum voltage of pwm signal into analog voltage, driving voltage Vout=(VH-VL) α, VH, and VL is pwm signal
Minimum voltage, α are the dutycycles of PWM ripples.Therefore pwm signal can be converted to the analog signal directly proportional to dutycycle.The
Three triode Q3 and the 4th triode Q4 composition push-pull circuits, further enhance driving force.
The operation principle of LED light adjusting circuits provided in an embodiment of the present invention is as follows：
1st, when that need not be dimmed, the first dimmer switch S2 and the second dimmer switch S3 closures, dim signal are also
Sine wave, first square-wave signal are with the square-wave signal at half period interval, the PWM controls with second square-wave signal
Circuit 3 processed does not detect that the first square-wave signal has lacked square wave, does not detect that the second square-wave signal has lacked square wave yet, because
The dutycycle of this pwm signal will not adjust.
2nd, when needing to increase brightness, the first dimmer switch S2 is disconnected, and keeps the second dimmer switch S3 closures, it is described
Dim signal is the waveform that sine wave cuts away positive half-wave, the first square wave signal output low level, second square-wave signal
Output frequency is 50HZ square wave, and the pwm control circuit 3 is according to detecting number that the first square-wave signal lacks (actually
Corresponding to the first dimmer switch S2 turn-off time) dutycycle of pwm signal is improved, so as to increasing LED brightness.
3rd, when needing to reduce brightness, the second dimmer switch S3 is disconnected, and keeps the first dimmer switch S2 closures, it is described
Dim signal is the waveform that sine wave cuts away negative half-wave, the second square wave signal output low level, first square-wave signal
Output frequency is 50HZ square wave, and the pwm control circuit 3 is according to detecting number that the second square-wave signal lacks (actually
Corresponding to the second dimmer switch S3 turn-off time) dutycycle of pwm signal is reduced, so as to reducing LED brightness.
4th, when the dutycycle of pwm signal reaches maximum (100%), continue to take the operation of increase brightness to there will not be change
Change, with should the dutycycle of pwm signal reach minimum when, continue to take the operation for reducing brightness to there will not be change.
5th, when increasing to suitable brightness, the first dimmer switch S2 is closed automatically, so as to keep the present brightness of LED,
Similarly, when being reduced to suitable brightness, the second dimmer switch S3 is closed automatically, so as to keep the present brightness of LED.
LED light adjusting circuits provided in an embodiment of the present invention have the beneficial effect that：By dim signal generation circuit 1 to fire
The copped wave of line signal produces two-way square-wave signal, PWM controls respectively to produce dim signal by dim signal change-over circuit 2
Circuit 3 controls the dutycycle of pwm signal according to the two-way square-wave signal, so as to change the brightness of LED.Using single live wire
Mode controls LED illumination lamp brightness, without remote control, without control line, without laying power line again, it is possible to achieve common
The replacement upgrading of illuminating lamp, cost is low, and jamproof ability is strong.
One of ordinary skill in the art will appreciate that realize all or part of flow in above-described embodiment method, being can be with
The hardware of correlation is instructed to complete by computer program, described program can be stored in a computer read/write memory medium
In, the program is upon execution, it may include such as the flow of the embodiment of above-mentioned each method.Wherein, described storage medium can be magnetic
Dish, CD, read-only memory (Read-Only Memory, ROM) or random access memory (Random Access
Memory, RAM) etc..
Described above is the preferred embodiment of the present invention, it is noted that for those skilled in the art
For, under the premise without departing from the principles of the invention, some improvements and modifications can also be made, these improvements and modifications are also considered as
Protection scope of the present invention.
Claims (10)
1. a kind of LED light adjusting circuits, it is characterised in that including dim signal generation circuit, dim signal change-over circuit, PWM controls
Circuit and LED drive circuit processed；
The dim signal generation circuit includes power switch, the first diode, the second diode, the first dimmer switch and second
Dimmer switch, and there is live wire signal input part and dim signal output end；The first end of the power switch is connected to described
Live wire signal input part；The anode of first diode is connected to the power supply after being coupled with the negative electrode of second diode
Second end of switch；The negative electrode of first diode is connected by first dimmer switch and the dim signal output end
Connect；The anode of second diode is connected by second dimmer switch with the dim signal output end；Described first
Dimmer switch switchs with second dimmer switch for dynamic circuit breaker；
The dim signal change-over circuit is used for the light modulation letter for receiving neutral signal and dim signal generation circuit output
Number, and the first square-wave signal and the second square-wave signal are produced according to the neutral signal and the dim signal；
The pwm control circuit is used for according to first square-wave signal and second square-wave signal, adjusts accounting for for pwm signal
It is empty than and be output to the LED drive circuit；Wherein, the pwm control circuit is detecting that first square-wave signal lacks
During one square wave, dutycycle one grade of the pwm signal is improved, or detecting that second square-wave signal lacks
During one square wave, one grade of dutycycle of the pwm signal is reduced；
The LED drive circuit is used to drive the LED to light according to the pwm signal.
2. LED light adjusting circuits as claimed in claim 1, it is characterised in that the dim signal change-over circuit includes the first electricity
Resistance, second resistance, the first optocoupler, the second optocoupler, 3rd resistor, the 4th resistance, the 5th resistance, the 6th resistance, the 7th resistance,
Eight resistance, the first electric capacity, the second electric capacity, the first phase inverter and the second phase inverter；The first end of the first resistor is used to connect
Receive the dim signal；Second end of the first resistor is connected with the first input end of first optocoupler, and with described
The second input connection of two optocouplers；The first end of the second resistance is used to receive neutral signal；The of the second resistance
Two ends are connected with the first input end of second optocoupler, and are connected with the second input of first optocoupler；
First output end of first optocoupler connects DC voltage by the 3rd resistor, and the second of first optocoupler is defeated
Go out end and pass through the 4th resistance eutral grounding；The first end of 5th resistance is connected with the second output end of first optocoupler,
Second end of the 5th resistance is connected with the input of first phase inverter, and passes through first capacity earth；It is described
The output end of first phase inverter exports first square-wave signal；
First output end of second optocoupler connects DC voltage by the 6th resistance, and the second of second optocoupler is defeated
Go out end and pass through the 7th resistance eutral grounding；The first end of 8th resistance is connected with the second output end of second optocoupler,
Second end of the 8th resistance is connected with the input of second phase inverter, and passes through second capacity earth；It is described
The output end of second phase inverter exports second square-wave signal.
3. LED light adjusting circuits as claimed in claim 1, it is characterised in that
The dim signal change-over circuit includes the first low pass active filter circuit, the first RC filter circuits, first voltage and followed
Circuit, the first bleeder circuit, the first comparison circuit, the second low pass active filter circuit, the 2nd RC filter circuits, second voltage with
With circuit, the second bleeder circuit and the second comparison circuit；
The input of the first low pass active filter circuit is used to receive the dim signal, the first low pass active power filtering
The output end of circuit pass sequentially through the first RC filter circuits and first voltage to follow circuit to be connected to first comparison electric
The first input end on road；The first input end of first comparison circuit is connected to described second by first bleeder circuit
Second input of comparison circuit；The output end of first comparison circuit exports first square-wave signal；
The input of the second low pass active filter circuit is used to receive the neutral signal, the second low pass active power filtering
The output end of circuit pass sequentially through the 2nd RC filter circuits and second voltage to follow circuit to be connected to second comparison electric
The first input end on road；The first input end of second comparison circuit is connected to described first by second bleeder circuit
Second input of comparison circuit；The output end of second comparison circuit exports second square-wave signal.
4. LED light adjusting circuits as claimed in claim 3, it is characterised in that
The first low pass active filter circuit include first resistor, second resistance, the first electric capacity, the first operational amplifier and
3rd resistor；The first end of the first resistor is the input of the first low pass active circuit, the of the first resistor
Two ends are grounded by the second resistance；First electric capacity is in parallel with the second resistance；Second end of the first resistor
It is connected with the normal phase input end of first operational amplifier；The both ends of the 3rd resistor connect first computing and put respectively
The inverting input and output end of big device；The output end of first operational amplifier is the first low pass active power filtering electricity
The output end on road；
The second low pass active filter circuit include the 4th resistance, the 5th resistance, the second electric capacity, the second operational amplifier and
6th resistance；The first end of 4th resistance is the input of the second low pass active circuit, the of the 4th resistance
Two ends pass through the 5th resistance eutral grounding；Second electric capacity and the 5th resistor coupled in parallel；Second end of the 4th resistance
It is connected with the normal phase input end of second operational amplifier；The both ends of 6th resistance connect second computing and put respectively
The inverting input and output end of big device；The output end of second operational amplifier is the second low pass active power filtering electricity
The output end on road.
5. LED light adjusting circuits as claimed in claim 4, it is characterised in that
The first RC filter circuits include the 7th resistance and the 3rd electric capacity；The first end of 7th resistance is low with described first
The output end connection of power filter is connected with, the second end of the 7th resistance passes through the 3rd capacity earth；Described 7th
The output end of resistance is the output end of the first RC filter circuits；
The 2nd RC filter circuits include the 8th resistance and the 4th electric capacity；The first end of 8th resistance is low with described second
The output end connection of power filter is connected with, the second end of the 8th resistance passes through the 4th capacity earth；Described 8th
The output end of resistance is the output end of the 2nd RC filter circuits.
6. LED light adjusting circuits as claimed in claim 5, it is characterised in that
The first voltage follows circuit to include the 3rd operational amplifier and the 9th resistance；3rd operational amplifier is just
Phase input is the input that the first voltage follows circuit, and the output end of the 3rd operational amplifier is the described first electricity
Pressure follows the output end of circuit, the both ends of the 9th resistance connect respectively the inverting input of the 3rd operational amplifier with
Output end；
The second voltage follows circuit to include four-operational amplifier and the tenth resistance；The four-operational amplifier is just
Phase input is the input that the second voltage follows circuit, and the output end of the four-operational amplifier is the described second electricity
Pressure follows the output end of circuit, the both ends of the tenth resistance connect respectively the inverting input of the four-operational amplifier with
Output end.
7. LED light adjusting circuits as claimed in claim 6, it is characterised in that first bleeder circuit includes the 11st resistance
With the 12nd resistance；The first end of 11st resistance be first bleeder circuit input, the 11st resistance
The second end be first bleeder circuit output end；Second end of the 11st resistance is connect by the 12nd resistance
Ground；
Second bleeder circuit includes the 13rd resistance and the 14th resistance；The first end of 13rd resistance is described the
The input of two bleeder circuits, the second end of the 13rd resistance are the output end of second bleeder circuit；Described tenth
Second end of three resistance passes through the 14th resistance eutral grounding.
8. LED light adjusting circuits as claimed in claim 7, it is characterised in that
First comparison circuit includes the 5th operational amplifier and the 15th resistance；5th operational amplifier it is anti-phase defeated
Enter first input end of the end for first comparison circuit, the normal phase input end of the 5th operational amplifier is the described first ratio
Compared with the second input of circuit, the output end of the 5th operational amplifier is the output end of first comparison circuit, described
The both ends of 15th resistance connect the normal phase input end and output end of the 3rd operational amplifier respectively；
Second comparison circuit includes the 6th operational amplifier and the 16th resistance；6th operational amplifier it is anti-phase defeated
Enter first input end of the end for second comparison circuit, the normal phase input end of the 6th operational amplifier is the described second ratio
Compared with the second input of circuit, the output end of the 6th operational amplifier is the output end of second comparison circuit, described
The both ends of 16th resistance connect the normal phase input end and output end of the 6th operational amplifier respectively.
9. LED light adjusting circuits as claimed in claim 1, it is characterised in that the LED drive circuit include the 18th resistance,
19th resistance, the first triode, the 20th resistance；The first end of 18th resistance is defeated for the LED drive circuit
Enter end；Second end of the 18th resistance is connected with the base stage of first triode, and is connect by the 19th resistance
Ground；The grounded emitter of first triode；The output of the extremely described LED drive circuit of current collection of first triode
End, is connected by the 20th resistance with DC voltage.
10. LED light adjusting circuits as claimed in claim 1, it is characterised in that the LED drive circuit includes the 21st electricity
Resistance, the second triode, the 22nd resistance, the 23rd resistance, the 24th resistance, the 6th electric capacity, the 3rd triode, the 4th
Triode and the 3rd diode；The first end of 21st resistance is the input of the LED drive circuit, described the
Second end of 21 resistance is connected to the base stage of second triode；The grounded emitter of second triode, current collection
The of the first end of pole and the 22nd resistance, the first end of the 23rd resistance and the 24th resistance
One end connects；The second end ground connection of 22nd resistance；Second end of the 23rd resistance and the three or three pole
The base stage of pipe, the connection of the base stage of the 4th triode, and pass through the 6th capacity earth；The of 24th resistance
Two ends are connected with DC voltage；The positive pole of 3rd diode is connected with DC voltage, negative pole and the 4th triode
Colelctor electrode connects；The emitter stage of 4th triode is connected with the emitter stage of the 3rd triode, is driven as the LED
The output end of circuit；The grounded collector of 3rd triode；The polarity of 3rd triode and the 4th triode
Conversely.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106507544A (en) * | 2016-12-21 | 2017-03-15 | 广东南能汇智节能科技有限公司 | A kind of LED lamplight brightness adjusting method and device |
| CN106413209B (en) * | 2016-12-21 | 2018-11-16 | 广东南能汇智节能科技有限公司 | A kind of LED lamplight brightness adjusting method |
| CN108182884A (en) * | 2017-12-29 | 2018-06-19 | 重庆锐虎光电科技有限公司 | The LED electronical display terminals that can be interacted with mobile terminal |
| CN112020175B (en) * | 2019-05-13 | 2024-06-14 | 广东芯神科技有限公司 | LED dimming circuit and equipment |
| CN112996186A (en) * | 2019-12-18 | 2021-06-18 | 安徽展晖电子科技有限公司 | Pulse-controlled circuit unit, drive circuit, integrated circuit and lighting device |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012034489A (en) * | 2010-07-30 | 2012-02-16 | Mitsumi Electric Co Ltd | Insulated power source unit and lighting device |
| CN203851328U (en) * | 2014-03-24 | 2014-09-24 | 佛山市永晨电子科技有限公司 | An LED drive circuit supporting light modulation by a silicon controlled rectifier |
| CN204157102U (en) * | 2014-08-11 | 2015-02-11 | 广东良得光电科技有限公司 | A kind of isolated single-stage PFC of flyback and TRIAC Dimmable LED drive circuit |
| CN204291440U (en) * | 2014-10-08 | 2015-04-22 | 广东百正节能服务有限公司 | Be applicable to LED lamp and the illuminator of AC power |
-
2015
- 2015-07-31 CN CN201510468409.0A patent/CN105025636B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012034489A (en) * | 2010-07-30 | 2012-02-16 | Mitsumi Electric Co Ltd | Insulated power source unit and lighting device |
| CN203851328U (en) * | 2014-03-24 | 2014-09-24 | 佛山市永晨电子科技有限公司 | An LED drive circuit supporting light modulation by a silicon controlled rectifier |
| CN204157102U (en) * | 2014-08-11 | 2015-02-11 | 广东良得光电科技有限公司 | A kind of isolated single-stage PFC of flyback and TRIAC Dimmable LED drive circuit |
| CN204291440U (en) * | 2014-10-08 | 2015-04-22 | 广东百正节能服务有限公司 | Be applicable to LED lamp and the illuminator of AC power |
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