CN110012575A - Drive control circuit and control method - Google Patents
Drive control circuit and control method Download PDFInfo
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- CN110012575A CN110012575A CN201910385369.1A CN201910385369A CN110012575A CN 110012575 A CN110012575 A CN 110012575A CN 201910385369 A CN201910385369 A CN 201910385369A CN 110012575 A CN110012575 A CN 110012575A
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Abstract
Present invention discloses a kind of drive control circuit and control method, the drive control circuit includes: input voltage feed forward unit, benchmark generation unit；Input voltage feed forward unit is used to receive the signal of DC bus-bar voltage Vin, and feedback signal transmission a to benchmark is generated unit；Benchmark generates unit to generate reference voltage Vref according to from the received feedback signal of the input voltage feed forward unit；After DC bus-bar voltage Vin is greater than preset second voltage VAC2, at least there is a period or a time point, benchmark generates the reference voltage Vref that unit generates and reduces with the increase of DC bus-bar voltage Vin.The present invention can reduce LED operation electric current, to effectively control the power consumption of LED drive control chip, effectively prevent the damage of LED drive control chip, guarantee the normal work of drive control chip.
Description
Technical field
The invention belongs to field of LED drive technologies, are related to a kind of LED drive circuit more particularly to a kind of drive control electricity
Road and control method.
Background technique
Semiconductor devices of the LED as characteristic sensitivity, needs direct current to be driven, the brightness and driving current of LED light
It is related.Fig. 1 shows the circuit diagram of Buck type LED drive circuit in the prior art.As shown in Figure 1, LED drive circuit includes whole
Flow filter circuit, LED drive control chip and output-stage circuit.Current rectifying and wave filtering circuit includes rectifier bridge and capacitor C1.Wherein, whole
Flowing bridge for the alternating voltage AC rectifying and wave-filtering of input is DC bus-bar voltage Vin, and is stored in capacitor C1.DC bus-bar voltage
The HVDD pin of Vin access LED drive control chip.CS pin is sampling pin, flows through LED drive control chip for acquiring
The electric current of internal switching tube Q.CS pin is connected with sampling resistor Rcs.GND pin is grounding pin.OVP draws for open-circuit-protection
Foot is connected with open-circuit-protection resistance Rovp, realizes output over-voltage protection.Output-stage circuit includes inductance L, diode D1 and capacitor
C2, diode D1 are connected between the DRAIN pin and DC bus-bar voltage Vin of LED drive control chip, and inductance L is connected to
Between the DRAIN pin of LED drive control chip and the output end vo ut of output-stage circuit；Capacitor C2 is connected to DC bus
Between voltage Vin and output end vo ut.LED load includes multiple concatenated LED, be connected in parallel DC bus-bar voltage Vin and
Between output end vo ut.The DC powered LED load that output-stage circuit is exported according to LED drive control chip.
When the switching tube Q conducting that LED drive control chip interior integrates, energy storage, inductive current IL mono- are carried out to inductance L
It is straight to rise, when being greater than reference voltage Vref to the voltage Vcs of sampling resistor Rcs, control circuit is output control signals to, to control
Switching tube Q shutdown processed.When the switching tube Q shutdown that LED drive control chip interior integrates, inductance L provides energy, inductive current
IL can not instantaneous abrupt change.Therefore, inductive current IL is gradually reduced, until being reduced to zero, zero passage detection unit passes through driving at this time
When signal learns that inductive current IL is zero, then a zero passage detection signal ZCD is sent to control circuit, so that control circuit occurs
It resets, control switch pipe Q conducting.The conducting control of switching tube Q is realized by control turn-on time.That is, passing through sampling
The voltage Vcs of resistance Rcs, and control Signal-controlled switch pipe Q on-off is exported, to realize closed-loop control.When sampled voltage Vcs is big
When reference voltage Vref, LED drive control chip on-off switching tube Q, when inductive current IL is discharged to zero, LED driving control
Switching tube Q is connected in coremaking piece, in this way repeating signal.Therefore, the switching tube Q of LED drive control chip interior is being opened
Switch repeatedly between off status, so that LED drive control chip operation is under critical conduction mode.
As shown in Fig. 2, its course of work are as follows: when zero passage detection unit learns that inductive current IL is zero by driving signal
When, control switch pipe Q conducting.CS pin voltage is lower than reference voltage Vref, and amplifier EA persistently charges to capacitor C3, electricity
Appearance C3 is compensating unit, to form offset voltage.The sawtooth wave that sawtooth wave generating unit issues passes through comparator and offset voltage
It is compared, to export control signal.When sawtooth signal value is greater than offset voltage, control switch pipe is closed, and is otherwise opened
Close pipe constant conduction.In addition, maximum turn-on time is arranged according to LED drive circuit, when switching tube Q constant conduction, timer is arrived
Up to maximum turn-on time, even if CS pin voltage is lower than reference voltage Vref, control switch pipe Q closing is still needed to.
Less developed country has that national grid voltage output is unstable.In addition, Compact Power Plant also has output electricity
Press unstable problem.Network voltage output is fluctuated, and the power output for easily leading to electrical equipment is unstable, to cause to use
Electric equipment calorific value is excessive and damages device element.
As shown in figure 3, input voltage VAC1 corresponds to the maximum operating currenbt of LED, when input voltage is less than VAC1, with
The operating current of the increase of input voltage, LED is gradually increased.When input voltage is equal to VAC1, CS pin voltage is equal to benchmark
Voltage Vref.When input voltage is much larger than VAC1, input voltage is higher, and main harm is the voltage stress of device in circuit
Larger, the power consumption of LED drive control chip is excessively high, and calorific value is excessive, and easily causing LED drive control wafer damage or reducing it makes
Use the service life.
In the prior art, it is fixed that benchmark, which generates the Vref that unit generates,.Therefore, when network voltage is excessive can not and
When on-off switching tube Q.
In view of this, nowadays there is an urgent need to design a kind of LED drive control mode, to overcome existing LED driving method
Existing drawbacks described above.
Summary of the invention
The present invention provides a kind of drive control circuit and control method, LED operation electric current can be reduced, to effectively control
The power consumption of LED drive control chip effectively prevent the damage of LED drive control chip, guarantees the normal work of drive control chip
Make.
In order to solve the above technical problems, according to an aspect of the present invention, adopting the following technical scheme that
A kind of drive control circuit, the drive control circuit include:
Input voltage feed forward unit, for receiving the signal of DC bus-bar voltage Vin, and by feedback signal transmission a to base
Standard generates unit；
Benchmark generates unit, to generate reference voltage according to from the received feedback signal of the input voltage feed forward unit
Vref；It is greater than preset second voltage V in DC bus-bar voltage VinAC2Afterwards, at least there is a period or a time point,
Benchmark generates the reference voltage Vref that unit generates and reduces with the increase of DC bus-bar voltage Vin；
The drive control circuit controls the operating current of LED according to corresponding reference voltage Vref.
As one embodiment of the present invention, the drive control circuit further includes switching tube Q, switch controlled electricity
Road, the switch controlled circuit are separately connected benchmark and generate unit and switching tube Q；The switch controlled circuit is according to correspondence
Reference voltage Vref, the on-off of control switch pipe Q, to control the operating current of LED.
As one embodiment of the present invention, the switch controlled circuit includes amplifier EA, third capacitor C3, most
Big turn-on time acquiring unit, zero passage detection unit, sawtooth wave generating unit, comparator or door and rest-set flip-flop；
The output end connection benchmark of the input voltage feed forward unit generates unit, and benchmark generates the output end connection of unit
The normal phase input end of amplifier EA, the inverting input terminal of the source electrode connection amplifier EA of switching tube Q；
The output end of the amplifier EA be separately connected the inverting input terminal of the comparator, third capacitor C3 first
End, the second end ground connection of third capacitor C3；The normal phase input end of the comparator connects sawtooth wave generating unit, comparator it is defeated
The first input end of the second input terminal or door of outlet connection or door connects maximum turn-on time acquiring unit；
Second end input terminal R of described or door output end connection rest-set flip-flop, zero passage detection unit are separately connected RS touching
Send out the end first input end S of device, the end output end Q, switching tube Q grid.
As one embodiment of the present invention, when input voltage is less than preset first voltage VAC1When, with input electricity
The operating current of the increase of pressure, the drive control circuit LED is gradually increased；Wherein, first voltage VAC1Corresponding LED's
Default operating current；
When input voltage is greater than first voltage VAC1, it is less than second voltage VAC2When, the drive control circuit LED with
Default operating current works；When input voltage is greater than second voltage VAC2When, the work of the drive control circuit LED
It will be less than default operating current as electric current, i.e., reduce with the increase of input voltage.
As one embodiment of the present invention, it is greater than preset second voltage V in DC bus-bar voltage VinAC2Afterwards, base
Standard generates the reference voltage Vref that unit generates and reduces with the increase of DC bus-bar voltage Vin.
As one embodiment of the present invention, when DC bus-bar voltage Vin is less than preset second voltage VAC2When, base
Standard generates the reference voltage Vref that unit generates and does not change；The second voltage VAC2It can be born for LED drive control chip
Input voltage corresponding to voltage.
As one embodiment of the present invention, the drive control circuit includes current rectifying and wave filtering circuit, LED drive control
Chip and output-stage circuit；The input voltage feed forward unit, benchmark generate one of unit as LED drive control chip
Point, alternatively, except the input voltage feed forward unit or/and benchmark generate unit independently of the LED drive control chip.
As one embodiment of the present invention, when input voltage is less than preset first voltage VAC1When, with input electricity
The operating current of the increase of pressure, LED is gradually increased；When input voltage is equal to first voltage VAC1When, LED drive control chip
CS pin voltage is equal to reference voltage Vref；First voltage VAC1The default operating current of corresponding LED；
When input voltage is greater than first voltage VAC1, it is less than second voltage VAC2When, LED carries out work with default operating current
Make；When input voltage is greater than second voltage VAC2When, the operating current of LED will be less than default operating current, i.e., with input voltage
Increase and reduce；
The HVDD pin of the input voltage feed forward unit connection LED drive control chip, input voltage feed forward unit are used
Unit is generated in the signal for receiving DC bus-bar voltage Vin, and by feedback signal transmission to benchmark；Benchmark generates unit according to anti-
Feedback signal generates reference voltage Vref；
When DC bus-bar voltage Vin is less than second voltage VAC2When, benchmark generates the reference voltage Vref that unit generates and does not send out
It is raw to change；When DC bus-bar voltage Vin is greater than second voltage VAC2When, benchmark generate unit generate reference voltage Vref with
The increase of Vin and reduce；The LED drive control die chip is according to the real-time regulating switch pipe Q's of corresponding reference voltage Vref
Turn-on time reduces LED operation electric current.
A kind of drive control circuit, the drive control circuit include: that input voltage feed forward unit and benchmark generate unit；
Input voltage feed forward unit, for receiving the signal of DC bus-bar voltage Vin, and by feedback signal transmission to described
Benchmark generates unit；
The benchmark generate unit based on the received the variation of feedback signal and change reference voltage Vref.
A kind of drive control method, the drive control method include:
Receive the signal of DC bus-bar voltage Vin；
Feedback signal generates reference voltage Vref based on the received；It is greater than preset second electricity in DC bus-bar voltage Vin
Press VAC2Afterwards, at least there is a period or a time point, the reference voltage Vref of generation is with DC bus-bar voltage Vin
Increase and reduce；
The drive control circuit is according to corresponding reference voltage Vref, the operating current of real-time control LED.
As one embodiment of the present invention, when input voltage is greater than second voltage VAC2When, the operating current of LED will
Lower than default operating current, i.e., reduce with the increase of input voltage.
As one embodiment of the present invention, when input voltage is less than preset first voltage VAC1When, with input electricity
The increase of pressure, the operating current for controlling LED are gradually increased；When input voltage is equal to first voltage VAC1When, LED drive control core
The CS pin voltage of piece is equal to reference voltage Vref；First voltage VAC1The default operating current of corresponding LED；
When input voltage is greater than first voltage VAC1, it is less than second voltage VAC2When, it controls LED and is carried out with default operating current
Work.
As one embodiment of the present invention, it is greater than preset second voltage V in DC bus-bar voltage VinAC2Afterwards, base
Standard generates the reference voltage Vref that unit generates and reduces with the increase of DC bus-bar voltage Vin.
As one embodiment of the present invention, when DC bus-bar voltage Vin is less than preset second voltage VAC2When, base
Standard generates the reference voltage Vref that unit generates and does not change；The second voltage VAC2It can be born for LED drive control chip
Input voltage corresponding to voltage.
The beneficial effects of the present invention are: drive control circuit and control method proposed by the present invention, it can be with input electricity
The variation of pressure and change reference voltage Vref, with the make-and-break time of regulating switch pipe Q, LED operation electric current is reduced, to effectively control
The power consumption of LED drive control chip processed, calorific value are controlled, and the damage of LED drive control chip is effectively prevent, and guarantee driving
Control the normal work of chip.
When input voltage is less than VAC2, it is still fixed value that benchmark, which generates the reference voltage Vref that unit generates, can be kept
The normal work of LED.When input voltage is greater than VAC2, reference voltage Vref reduces with the increase of input voltage, thus
Io value is reduced, is maintained at the power of drive control chip in reasonable range, in the unstable network operation ring of input voltage
Under border, the drive control chip of this programme can make LED continually and steadily work.
Detailed description of the invention
Fig. 1 is the circuit diagram of existing LED drive circuit.
Fig. 2 is the composition schematic diagram of existing LED drive control chip.
Fig. 3 is the relational graph of existing LED drive circuit corresponding LED operation electric current and input voltage.
Fig. 4 is the composition schematic diagram of LED drive control chip in one embodiment of the invention.
Fig. 5 is the relational graph of LED operation electric current and input voltage in one embodiment of the invention.
Fig. 6 is the relational graph of reference voltage Vref and input voltage in one embodiment of the invention.
Fig. 7 is the circuit diagram that input voltage feed forward unit and benchmark generate unit in one embodiment of the invention.
Specific embodiment
The preferred embodiment that the invention will now be described in detail with reference to the accompanying drawings.
For a further understanding of the present invention, the preferred embodiment of the invention is described below with reference to embodiment, still
It should be appreciated that these descriptions are only further explanation the features and advantages of the present invention, rather than to the claims in the present invention
Limitation.
Just for several typical embodiments, the present invention is not limited merely to the model of embodiment description for the description of the part
It encloses.Some technical characteristics in same or similar prior art means and embodiment, which are replaced mutually, also to be described in the present invention
In the range of protection.
Present invention discloses a kind of drive control circuit, the drive control circuit includes: input voltage feed forward unit, base
Standard generates unit.
In one embodiment of this invention, input voltage feed forward unit is used to receive the signal of DC bus-bar voltage Vin, and
Feedback signal transmission a to benchmark is generated into unit.Benchmark generates unit to receive according to from the input voltage feed forward unit
Feedback signal generate reference voltage Vref；It is greater than preset second voltage V in DC bus-bar voltage VinAC2Afterwards, at least exist
One period or a time point, benchmark generate the reference voltage Vref of unit generation with the increasing of DC bus-bar voltage Vin
Reduce greatly；The drive control circuit is according to corresponding reference voltage Vref, the operating current of real-time control LED.
In another embodiment of the invention, input voltage feed forward unit is used to receive the signal of DC bus-bar voltage Vin,
And feedback signal transmission to the benchmark is generated into unit.The benchmark generate unit based on the received the variation of feedback signal and
Change reference voltage Vref, (when reference voltage Vref is reduced, cs pin reaches lower with the make-and-break time of regulating switch pipe Q
Voltage, will control switch pipe Q turn off the switch pipe Q under shorter turn-on time), reduce LED operation electric current.Benchmark Vref drop
Voltage, which can reduce, after low, on compensating unit (third capacitor C3) reduces so as to cause Ton turn-on time and exports current reduction, this
It is that the principle automatically controlled determines.
In one embodiment of this invention, the drive control circuit further includes switching tube Q, switch controlled circuit, institute
It states switch controlled circuit and is separately connected benchmark generation unit and switching tube Q；The switch controlled circuit is according to corresponding base
Quasi- voltage Vref, the on-off of control switch pipe Q, to control the operating current of LED.
In one embodiment of this invention, in combination with Fig. 4, the switch controlled circuit includes amplifier EA, third electricity
Hold C3, maximum turn-on time acquiring unit, zero passage detection unit, sawtooth wave generating unit, comparator or door and RS triggering
Device.The output end connection benchmark of the input voltage feed forward unit generates unit, and the output end that benchmark generates unit connects amplification
The normal phase input end of device EA, the inverting input terminal of the source electrode connection amplifier EA of switching tube Q.The output end of the amplifier EA point
The inverting input terminal of the comparator, the first end of third capacitor C3, the second end ground connection of third capacitor C3 are not connected；The ratio
Normal phase input end compared with device connects sawtooth wave generating unit, the output end connection of comparator or second input terminal or door of door
First input end connects maximum turn-on time acquiring unit.Second input terminal R of described or door output end connection rest-set flip-flop
End, zero passage detection unit be separately connected the end first input end S of rest-set flip-flop, the end output end Q, switching tube Q grid.
In one embodiment of this invention, it is greater than preset second voltage V in DC bus-bar voltage VinAC2Afterwards, benchmark produces
The reference voltage Vref that raw unit generates reduces with the increase of DC bus-bar voltage Vin.When DC bus-bar voltage Vin is less than
Preset second voltage VAC2When, benchmark generates the reference voltage Vref that unit generates and does not change.In an implementation of the invention
In example, the second voltage VAC2Input voltage corresponding to voltage can be born for LED drive control chip.It is of course also possible to will
Second voltage VAC2It is set as other voltages.
In combination with Fig. 1, in one embodiment of this invention, the drive control circuit includes current rectifying and wave filtering circuit, LED drive
Dynamic control chip and output-stage circuit；The input voltage feed forward unit, benchmark generate unit as LED drive control chip
A part.
In one embodiment of this invention (in combination with Fig. 1), the current rectifying and wave filtering circuit includes rectifier bridge and first capacitor
C1.Wherein, the alternating voltage AC rectifying and wave-filtering of input is DC bus-bar voltage Vin by rectifier bridge, and is stored in first capacitor
C1.The HVDD pin of DC bus-bar voltage Vin access LED drive control chip；CS pin is sampling pin, is flowed through for acquiring
The electric current of the switching tube Q of LED drive control chip interior；CS pin is connected with sampling resistor Rcs；GND pin is grounding pin；
ROVP pin is open-circuit-protection pin, is connected with open-circuit-protection resistance Rovp, realizes output over-voltage protection.
In one embodiment of this invention (in combination with Fig. 1), the output-stage circuit includes inductance L, first diode D1
With the second capacitor C2.The anode of first diode D1 is separately connected the first DRAIN pin, the 2nd DRAIN pin, first diode
The cathode of D1 connects DC bus-bar voltage Vin；The first end of inductance L is separately connected the first DRAIN pin, the 2nd DRAIN pin,
The output end vo ut of the second end connection output-stage circuit of inductance L；Second capacitor C2 is connected to DC bus-bar voltage Vin and output
It holds between Vout；LED load includes multiple concatenated LED, be connected in parallel DC bus-bar voltage Vin and output end vo ut it
Between；The DC powered LED load that output-stage circuit is exported according to LED drive control chip.
In an embodiment of the present invention (in combination with Fig. 1), the LED drive control chip is equipped with ROVP pin, GND draws
Foot, NC pin, HVDD pin, the first DRAIN pin, the 2nd DRAIN pin, CS pin.
Fig. 4 is the composition schematic diagram of LED drive control chip in one embodiment of the invention；Referring to Fig. 4, in the present invention one
In embodiment, the LED drive control chip includes that input voltage feed forward unit 11, benchmark generate unit 12, amplifier EA, the
Three capacitor C3, maximum turn-on time acquiring unit 15, zero passage detection unit 17, sawtooth wave generating unit 13, comparator 14 or door
16, rest-set flip-flop 18 and switching tube Q.In one embodiment of this invention, input voltage feed forward unit 11 or/and benchmark generate
Except unit 12 is independently of the LED drive control chip.
The output end connection benchmark of the input voltage feed forward unit 11 generates unit 12, and benchmark generates the output of unit 12
The normal phase input end of end connection amplifier EA, the inverting input terminal of the source electrode connection amplifier EA of switching tube Q.The amplifier EA
Output end be separately connected the first end of the inverting input terminal of the comparator 14, third capacitor C3, the second of third capacitor C3
End ground connection；The normal phase input end of the comparator 14 connects sawtooth wave generating unit 13, the output end connection of comparator 14 or door
16 the second input terminal or the first input end of door 16 connect maximum turn-on time acquiring unit 15.Maximum turn-on time obtains
Maximum turn-on time of the unit 15 to control switch pipe Q, when reaching maximum turn-on time, then control switch pipe Q is closed.Input
Voltage can reduce output electric current when reducing with fixed Tonmax.Described or door 16 output end connection rest-set flip-flop 18
Second end input terminal R, zero passage detection unit 17 are separately connected the end first input end S, the end output end Q, switch of rest-set flip-flop 18
The grid of pipe Q.
Fig. 5 is the relational graph of LED operation electric current and input voltage in one embodiment of the invention；Referring to Fig. 5, in the present invention
An embodiment in, in one embodiment of this invention, when input voltage be less than preset first voltage VAC1When, with input
The operating current of the increase of voltage, LED is gradually increased；When input voltage is equal to first voltage VAC1When, CS pin voltage is equal to base
Quasi- voltage Vref.When input voltage is greater than first voltage VAC1, it is less than second voltage VAC2When, LED is carried out with default operating current
Work；When input voltage is greater than second voltage VAC2When, the operating current of LED will be less than default operating current, i.e., with input electricity
The increase of pressure and reduce.Wherein, first voltage VAC1The default operating current of corresponding LED；In one embodiment of this invention, LED
Default operating current can be LED maximum operating currenbt.
Fig. 6 is the relational graph of reference voltage Vref and input voltage in one embodiment of the invention；Referring to Fig. 6, in this hair
In a bright embodiment, the HVDD pin of the input voltage feed forward unit connection LED drive control chip, input voltage feed forward
(Vin corresponds to V to signal of the unit for receiving DC bus-bar voltage VinAC), and feedback signal transmission to benchmark is generated into list
Member；Benchmark generates unit and generates reference voltage Vref based on the feedback signal.When DC bus-bar voltage Vin is less than VAC2When, benchmark produces
The reference voltage Vref that raw unit generates does not change；When DC bus-bar voltage Vin is greater than VAC2When, it is raw that benchmark generates unit
At reference voltage Vref reduce with the increase of Vin；Therefore, LED drive control chip can be according to corresponding reference voltage
Vref, the turn-on time of real-time regulating switch pipe Q, by reducing LED operation electric current, to effectively control LED drive control core
The power consumption of piece, calorific value are controlled, and the damage of LED drive control chip is effectively prevent, and guarantee the normal of drive control chip
Work.
It is common in other function circuit currently, input voltage feed forward unit or benchmark generate unit, this programme is in LED
Input voltage feed forward unit is added in drive control chip and benchmark generates unit, benchmark can be changed with the variation of input voltage
Voltage Vref, with the make-and-break time of regulating switch pipe Q, by reducing LED operation electric current, to effectively control LED drive control
The power consumption of chip.Wherein, the power consumption of metal-oxide-semiconductor mainly has switching loss and on-state loss.On-state loss: Pcond=Idsrms*
Idsrms*RDSon* Dmax, switching loss: Psw=VDSoff*Idsrms*(tr+tf)*f/2；Wherein, Pcond is on-state loss,
The channel current of MOSFET when Idsrms is conducting, RDSon is conducting resistance, Dmax is duty ratio；PSW is switching loss,
VDSoff is the drain-source voltage during MOSFET is turned off, and Idsrms is the channel current during MOSFET is connected, and tr and tf are to lead
The logical and turn-off time.When input voltage increases, in the case where operating current is constant, the power consumption of metal-oxide-semiconductor continues to increase.And it inputs
Voltage increases, by changing reference voltage Vref, so that LED operation electric current is reduced, it can be by metal-oxide-semiconductor power consumption control in zone of reasonableness
It is interior.
Fig. 7 is the circuit diagram that input voltage feed forward unit and benchmark generate unit in one embodiment of the invention；It please join
Fig. 7 is read, in one embodiment of this invention, the input voltage feed forward unit includes first resistor R1, second resistance R2, second
Diode D2, the 4th capacitor C4 and the first current source I1.The first of the second end connection second resistance R2 of the first resistor R1
It holds, the anode of the second diode D2, the second end ground connection of second resistance R2.The cathode output voltage of the second diode D2
The cathode of VB, the second diode D2 are separately connected the first end of the first end of the 4th capacitor C4, the first current source I1, the 4th capacitor
The second end of C4 is grounded, the second end ground connection of the first current source I1.
Please continue to refer to Fig. 7, in one embodiment of this invention, the benchmark generate unit include the second current source I2,
Voltage-controlled current source Ik, 3rd resistor R3 and zener diode D4.The output of the second current source I2 connects voltage-controlled current source Ik
First input end, the second input terminal of the cathode connection voltage-controlled current source Ik of the second diode D2, the of voltage-controlled current source Ik
Three input end groundings, the output end ground connection of voltage-controlled current source Ik, the third input terminal of voltage-controlled current source Ik is as reference voltage
The output end of Vref, the third input terminal of voltage-controlled current source Ik are separately connected the first end of 3rd resistor R3, zener diode D4
Cathode, 3rd resistor R3 second end ground connection, the plus earth of zener diode D4.
In one embodiment of this invention, the electric current output of the voltage-controlled current source Ik increases with the increase of voltage VB
Add；
Vref=(I2-Ik) * R3；
Ik=k*VB=k*k ' * VHVDD；
Wherein, the reference voltage value that unit generates is generated on the basis of Vref, I2 is the electric current of the second current source output, and Ik is
The electric current of voltage-controlled current source Ik output, R3 are the resistance value of 3rd resistor R3, and k is the control coefrficient of voltage-controlled current source, and k ' is VB
With VHVDDProportionality coefficient, VB be the second diode D2 negative pole end voltage, VHVDDFor LED drive control chip HVDD pin
The voltage at end.
When input voltage is less than second voltage VAC2, ID3=I2-Ik, the size of the electric current and reversely hitting for zener diode
Voltage is worn to compare；When electric current is larger, zener diode is reversed voltage breakdown, is controlled by zener diode, and benchmark generates single
The Vref that member generates is fixed value.
When input voltage is greater than second voltage VAC2, with the increase of input voltage, voltage VB also increases, thus Ik electric current
Increase, zener diode D4 is in reversed cut-off region, and reference voltage Vref reduces with the increase of input voltage.
The present invention also discloses a kind of drive control method, and the drive control method includes: to receive DC bus-bar voltage Vin
Signal；Feedback signal generates reference voltage Vref based on the received；It is greater than preset second voltage in DC bus-bar voltage Vin
VAC2Afterwards, at least there is a period or a time point, the reference voltage Vref of generation is with DC bus-bar voltage Vin's
Increase and reduces；The drive control circuit is according to corresponding reference voltage Vref, the operating current of real-time control LED.
In one embodiment of this invention, it is right for LED drive control chip can to bear voltage by the second voltage VAC2
The input voltage answered.
In one embodiment of this invention, when input voltage is less than preset first voltage VAC1When, with input voltage
Increase, the operating current for controlling LED is gradually increased (it is of course also possible to be to control LED at least one period or time point
Operating current be gradually increased with the increase of input voltage)；When input voltage is equal to first voltage VAC1When, LED driving control
The CS pin voltage of coremaking piece is equal to reference voltage Vref；First voltage VAC1The maximum operating currenbt of corresponding LED；When input electricity
Pressure is greater than first voltage VAC1, it is less than second voltage VAC2When, control LED is worked with maximum operating currenbt；Work as input voltage
Greater than second voltage VAC2When, the operating current of LED is controlled lower than maximum operating currenbt, i.e., subtracts with the increase of input voltage
It is small (it is of course also possible to be to control the operating current of LED at least one period or time point with the increase of input voltage
And reduce).
In one embodiment of this invention, after DC bus-bar voltage Vin is greater than preset second voltage VAC2, benchmark is produced
The reference voltage Vref that raw unit generates reduces with the increase of DC bus-bar voltage Vin.
In one embodiment of this invention, when DC bus-bar voltage Vin is less than preset second voltage VAC2, benchmark is produced
The reference voltage Vref that raw unit generates does not change.
In conclusion drive control circuit proposed by the present invention and control method, can change with the variation of input voltage
Variable reference voltage Vref reduces LED operation electric current with the make-and-break time of regulating switch pipe Q, thus effectively control LED driving control
The power consumption of coremaking piece, calorific value are controlled, and the damage of LED drive control chip is effectively prevent, and guarantee drive control chip
It works normally.
When input voltage is less than VAC2, it is still fixed value that benchmark, which generates the reference voltage Vref that unit generates, can be kept
The normal work of LED.When input voltage is greater than VAC2, reference voltage Vref reduces with the increase of input voltage, thus
Io value is reduced, is maintained at the power of drive control chip in reasonable range, in the unstable network operation ring of input voltage
Under border, the drive control chip of this programme can make LED continually and steadily work.
Description and application of the invention herein are illustrative, is not wishing to limit the scope of the invention to above-described embodiment
In.The deformation and change of embodiments disclosed herein are possible, the realities for those skilled in the art
The replacement and equivalent various parts for applying example are well known.It should be appreciated by the person skilled in the art that not departing from the present invention
Spirit or essential characteristics in the case where, the present invention can in other forms, structure, arrangement, ratio, and with other components,
Material and component are realized.Without departing from the scope and spirit of the present invention, can to embodiments disclosed herein into
The other deformations of row and change.
Claims (14)
1. a kind of drive control circuit, which is characterized in that the drive control circuit includes:
Input voltage feed forward unit is produced for receiving the signal of DC bus-bar voltage Vin, and by feedback signal transmission a to benchmark
Raw unit；
Benchmark generates unit, to generate reference voltage according to from the received feedback signal of the input voltage feed forward unit
Vref；It is greater than preset second voltage V in DC bus-bar voltage VinAC2Afterwards, at least there is a period or a time point,
Benchmark generates the reference voltage Vref that unit generates and reduces with the increase of DC bus-bar voltage Vin；
The drive control circuit controls the operating current of LED according to corresponding reference voltage Vref.
2. drive control circuit according to claim 1, it is characterised in that:
The drive control circuit further includes switching tube Q, switch controlled circuit, and the switch controlled circuit is separately connected base
Standard generates unit and switching tube Q；For the switch controlled circuit according to corresponding reference voltage Vref, control switch pipe Q's is logical
It is disconnected, to control the operating current of LED.
3. drive control circuit according to claim 2, it is characterised in that:
The switch controlled circuit includes amplifier EA, third capacitor C3, maximum turn-on time acquiring unit, zero passage detection list
Member, sawtooth wave generating unit, comparator or door and rest-set flip-flop；
The output end connection benchmark of the input voltage feed forward unit generates unit, and the output end that benchmark generates unit connects amplification
The normal phase input end of device EA, the inverting input terminal of the source electrode connection amplifier EA of switching tube Q；
The output end of the amplifier EA is separately connected the first end of the inverting input terminal of the comparator, third capacitor C3, the
The second end of three capacitor C3 is grounded；The normal phase input end of the comparator connects sawtooth wave generating unit, the output end of comparator
The first input end of the second input terminal or door of connection or door connects maximum turn-on time acquiring unit；
Second end input terminal R of described or door output end connection rest-set flip-flop, zero passage detection unit are separately connected rest-set flip-flop
The end first input end S, the end output end Q, switching tube Q grid.
4. drive control circuit according to claim 1, it is characterised in that:
When input voltage is less than preset first voltage VAC1When, with the increase of input voltage, the drive control circuit
The operating current of LED is gradually increased；Wherein, first voltage VAC1The default operating current of corresponding LED；
When input voltage is greater than first voltage VAC1, it is less than second voltage VAC2When, the drive control circuit LED is with default
Operating current works；When input voltage is greater than second voltage VAC2When, the work electricity of the drive control circuit LED
Stream will be less than default operating current, i.e., reduces with the increase of input voltage.
5. drive control circuit according to claim 1, it is characterised in that:
It is greater than preset second voltage V in DC bus-bar voltage VinAC2Afterwards, benchmark generate unit generate reference voltage Vref with
The increase of DC bus-bar voltage Vin and reduce.
6. drive control circuit according to claim 1, it is characterised in that:
When DC bus-bar voltage Vin is less than preset second voltage VAC2When, benchmark generates the reference voltage Vref of unit generation not
It changes；The second voltage VAC2Input voltage corresponding to voltage can be born for LED drive control chip.
7. drive control circuit according to claim 1, it is characterised in that:
The drive control circuit includes current rectifying and wave filtering circuit, LED drive control chip and output-stage circuit；The input electricity
Feed forward element, benchmark is pressed to generate a part of unit as LED drive control chip, alternatively, the input voltage feed forward unit
Or/and except benchmark generates unit independently of the LED drive control chip.
8. drive control circuit according to claim 6, it is characterised in that:
When input voltage is less than preset first voltage VAC1When, with the increase of input voltage, the operating current of LED gradually increases
Greatly；When input voltage is equal to first voltage VAC1When, the CS pin voltage of LED drive control chip is equal to reference voltage Vref；
First voltage VAC1The default operating current of corresponding LED；
When input voltage is greater than first voltage VAC1, it is less than second voltage VAC2When, LED is worked with default operating current；
When input voltage is greater than second voltage VAC2When, the operating current of LED will be less than default operating current, i.e., with input electricity
The increase of pressure and reduce；
The HVDD pin of the input voltage feed forward unit connection LED drive control chip, input voltage feed forward unit is for connecing
The signal of DC bus-bar voltage Vin is received, and feedback signal transmission to benchmark is generated into unit；Benchmark generates unit according to feedback letter
Number generate reference voltage Vref；
When DC bus-bar voltage Vin is less than second voltage VAC2When, benchmark generates the reference voltage Vref that unit generates and does not change
Become；When DC bus-bar voltage Vin is greater than second voltage VAC2When, benchmark generates the reference voltage Vref of unit generation with Vin's
Increase and reduces；When the LED drive control die chip is according to the conducting of the real-time regulating switch pipe Q of corresponding reference voltage Vref
Between, reduce LED operation electric current.
9. a kind of drive control circuit, which is characterized in that the drive control circuit includes: input voltage feed forward unit and benchmark
Generate unit；
Input voltage feed forward unit, for receiving the signal of DC bus-bar voltage Vin, and by feedback signal transmission to the benchmark
Generate unit；
The benchmark generate unit based on the received the variation of feedback signal and change reference voltage Vref.
10. a kind of drive control method, which is characterized in that the drive control method includes:
Receive the signal of DC bus-bar voltage Vin；
Feedback signal generates reference voltage Vref based on the received；It is greater than preset second voltage V in DC bus-bar voltage VinAC2
Afterwards, at least there is a period or a time point, the reference voltage Vref of generation with DC bus-bar voltage Vin increase
And reduce；
The drive control circuit is according to corresponding reference voltage Vref, the operating current of real-time control LED.
11. drive control method according to claim 10, it is characterised in that:
When input voltage is greater than second voltage VAC2When, the operating current of LED will be less than default operating current, i.e., with input electricity
The increase of pressure and reduce.
12. drive control method according to claim 11, it is characterised in that:
When input voltage is less than preset first voltage VAC1When, with the increase of input voltage, control the operating current of LED by
It is cumulative big；When input voltage is equal to first voltage VAC1When, the CS pin voltage of LED drive control chip is equal to reference voltage
Vref；First voltage VAC1The default operating current of corresponding LED；
When input voltage is greater than first voltage VAC1, it is less than second voltage VAC2When, LED, which is controlled, with default operating current carries out work
Make.
13. drive control method according to claim 10, it is characterised in that:
It is greater than preset second voltage V in DC bus-bar voltage VinAC2Afterwards, benchmark generate unit generate reference voltage Vref with
The increase of DC bus-bar voltage Vin and reduce.
14. drive control method according to claim 10, it is characterised in that:
When DC bus-bar voltage Vin is less than preset second voltage VAC2When, benchmark generates the reference voltage Vref of unit generation not
It changes；The second voltage VAC2Input voltage corresponding to voltage can be born for LED drive control chip.
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| CN201910385369.1A CN110012575B (en) | 2019-05-09 | 2019-05-09 | Drive control circuit and control method |
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| CN201910385369.1A CN110012575B (en) | 2019-05-09 | 2019-05-09 | Drive control circuit and control method |
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| CN110012575B CN110012575B (en) | 2024-04-19 |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110461066A (en) * | 2019-08-27 | 2019-11-15 | 杭州必易微电子有限公司 | For controlling control circuit, driving circuit and the control method of transistor |
| CN111465148A (en) * | 2020-05-20 | 2020-07-28 | 杭州必易微电子有限公司 | Load driving circuit, load driving control circuit and control method |
| CN112886955A (en) * | 2021-01-26 | 2021-06-01 | 深圳麦格米特电气股份有限公司 | Reference setting method and device of comparator, switching power supply and household appliance |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101977042A (en) * | 2010-09-28 | 2011-02-16 | 电子科技大学 | PWM or PSM dual-mode modulation control circuit used for switch voltage-stabilized supply |
| WO2011021836A2 (en) * | 2009-08-17 | 2011-02-24 | 단국대학교 산학협력단 | Light-emitting diode driving circuit capable of controlling the current of a constant light-emitting diode |
| KR20110090019A (en) * | 2010-02-02 | 2011-08-10 | 주식회사 미광엔비텍 | Light emitting diode driving circuit |
| CN102573235A (en) * | 2012-01-11 | 2012-07-11 | 杭州矽力杰半导体技术有限公司 | High-efficiency light-emitting diode (LED) driving circuit and driving method thereof |
| US20130038229A1 (en) * | 2011-08-11 | 2013-02-14 | Semiconductor Components Industries, Llc | Light-emitting device control circuit |
| US20150130363A1 (en) * | 2013-11-14 | 2015-05-14 | Samsung Electronics Co., Ltd. | Led driving device, lighting device, and control circuit for led driving device |
| EP2882264A2 (en) * | 2013-12-06 | 2015-06-10 | Semiconductor Components Industries, LLC | LED Control circuit and method |
| US20160044757A1 (en) * | 2014-08-06 | 2016-02-11 | Samsung Electronics Co., Ltd. | Led driving device and lighting apparatus |
| CN106211494A (en) * | 2015-05-04 | 2016-12-07 | 金宝电子工业股份有限公司 | Light emitting diode driving circuit |
| CN210351729U (en) * | 2019-05-09 | 2020-04-17 | 杭州必易微电子有限公司 | Drive control circuit |
-
2019
- 2019-05-09 CN CN201910385369.1A patent/CN110012575B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2011021836A2 (en) * | 2009-08-17 | 2011-02-24 | 단국대학교 산학협력단 | Light-emitting diode driving circuit capable of controlling the current of a constant light-emitting diode |
| KR20110090019A (en) * | 2010-02-02 | 2011-08-10 | 주식회사 미광엔비텍 | Light emitting diode driving circuit |
| CN101977042A (en) * | 2010-09-28 | 2011-02-16 | 电子科技大学 | PWM or PSM dual-mode modulation control circuit used for switch voltage-stabilized supply |
| US20130038229A1 (en) * | 2011-08-11 | 2013-02-14 | Semiconductor Components Industries, Llc | Light-emitting device control circuit |
| CN102573235A (en) * | 2012-01-11 | 2012-07-11 | 杭州矽力杰半导体技术有限公司 | High-efficiency light-emitting diode (LED) driving circuit and driving method thereof |
| US20150130363A1 (en) * | 2013-11-14 | 2015-05-14 | Samsung Electronics Co., Ltd. | Led driving device, lighting device, and control circuit for led driving device |
| EP2882264A2 (en) * | 2013-12-06 | 2015-06-10 | Semiconductor Components Industries, LLC | LED Control circuit and method |
| US20160044757A1 (en) * | 2014-08-06 | 2016-02-11 | Samsung Electronics Co., Ltd. | Led driving device and lighting apparatus |
| CN106211494A (en) * | 2015-05-04 | 2016-12-07 | 金宝电子工业股份有限公司 | Light emitting diode driving circuit |
| CN210351729U (en) * | 2019-05-09 | 2020-04-17 | 杭州必易微电子有限公司 | Drive control circuit |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110461066A (en) * | 2019-08-27 | 2019-11-15 | 杭州必易微电子有限公司 | For controlling control circuit, driving circuit and the control method of transistor |
| CN111465148A (en) * | 2020-05-20 | 2020-07-28 | 杭州必易微电子有限公司 | Load driving circuit, load driving control circuit and control method |
| CN112886955A (en) * | 2021-01-26 | 2021-06-01 | 深圳麦格米特电气股份有限公司 | Reference setting method and device of comparator, switching power supply and household appliance |
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|---|---|
| CN110012575B (en) | 2024-04-19 |
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