CN106358342A - Dimming driving circuit - Google Patents
Dimming driving circuit Download PDFInfo
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- CN106358342A CN106358342A CN201510435970.9A CN201510435970A CN106358342A CN 106358342 A CN106358342 A CN 106358342A CN 201510435970 A CN201510435970 A CN 201510435970A CN 106358342 A CN106358342 A CN 106358342A
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Abstract
The invention mainly relates to the field of driving of luminescent devices, and provides a dimming driving circuit for driving LED in a voltage conversion power supply system based on alternating current electric supply and a dimming method. Duty ratio of a PMW driving signal is linearly changed along with change of phase corner cut of alternating current. A dimming unit is used for detecting change conditions of a conduction angle of the alternating current, and meanwhile, the duty ratio of a modulating signal is further controlled to be changed along with trend of degree change of the conduction angle.
Description
Technical field
Present invention is primarily about luminescent device drives field, more precisely, being to supply in the voltage conversion based on electric main
Dimming driving circuit and the light-dimming method of led is driven, the dutycycle of achievable pwm drive signal is with friendship in electric system
The change of the electric phase place corner cut of stream and linear change.
Background technology
Increasingly serious with environmental resource problem with global energy, by energy-conserving and environment-protective and the advantage such as safe and reliable, solid-state light
The white light led in source is progressively referred to as the engine of green illumination, and therewith together, driving power supply then becomes led Lighting Industry
Particularly important link in chain, driving power supply is towards efficient and low-power consumption, and it is continuous with the trend of low cost to take into account safety and environmental protection
Development.We also need to be substantially a kind of DC driven device in view of led luminescent device simultaneously, it is desirable to provide constant
The drive circuit of electric current, consequently, it is possible to the driving chip of management white light led also serves as characterizing power management class product
Main flow direction and receive much concern, and be faced with the technological challenge needing sustained improvement properties.
Traditional electric filament lamp and fluorescent lamp commonly used bidirectional triode thyristor IGCT triac dimmer, promote white light led and shine
One of problem that bright technology is stood in the breach is exactly, how on the drive scheme of led compatible triac dimmer realizing shining
Bright intensity is adjustable.But regrettably, prior art rarely has offer efficient and can be instantaneous based on coming using triac dimmer
The drive scheme of the regulation led device intensity of illumination of response.And the present invention is exactly under the premise of this, by electric main
Voltage conversion while become DC voltage, synchronous also realize making pwm pulse drive signal using triac dimmer
Dutycycle with the change of alternating current phases corner cut and linear change.
Content of the invention
In one alternate embodiment, the present invention provided a kind of dimming driving circuit, comprising: a controllable silicon dimmer,
For adjusting the angle of flow of received alternating current；One electric pressure converter, because alternating current is cut through described controllable silicon dimmer
Phase angle exports and provides the input voltage of direct current after being rectified device rectification, and this electric pressure converter is by the input electricity of this direct current
Pressure produces default average value current and loads or provide output to load；One control module, control module is used for producing modulation
Signal, and the switching tube in described electric pressure converter switches between conducting and shutoff and is mainly used for defining whether using described
, to described Load transportation voltage and/or electric current, the transducer such as such as buck is in switching tube conducting phase input voltage for input voltage
Can to Load transportation voltage and/or electric current off-phases then cannot, also have contrary mode, such as flyback voltage conversion
In switching tube conducting phase input voltage, only to armature winding energy storage, off-phases then utilize the energy of storage to load to device etc.
Transmission voltage and/or electric current, and the modulated signal of wherein generation is exactly for driving or controlling the conducting of this switching tube and shutoff；
One dimming unit, for detecting the change of the angle of flow, and to embody the change of the angle of flow with an average voltage level of sampling
Change situation, while controllable silicon dimmer changes the angle of flow of alternating current, dimming unit also makes the dutycycle of modulated signal
Size variation trend be consistent with the size variation trend of the angle of flow, such as synchronous become big or diminish, in some cases also
Can allow this dutycycle size with the size variation of the angle of flow and linear change therewith.
Above-mentioned dimming driving circuit, described electric pressure converter is configured with different from the reference potential on the spot of described input voltage
One floating ground reference potential, make described switching tube when being driven by described modulated signal described modulated signal be electric with this floating ground reference
Position is reference ground, then described dimming unit captures described output voltage in the voltage output node sample of described electric pressure converter
Average voltage level；In described control module error amplifier relatively and amplify a reference voltage and a sign flow through negative
Difference between the feedback voltage of size of current carrying, the error voltage that described error amplifier is exported is in first electric capacity
Upper generation integral voltage, described dimming unit, when the described angle of flow reduces and causes described average voltage level to reduce, drags down described
The dutycycle that integral voltage forces described modulated signal with this reduces.For example in the topology such as buck, integral voltage and saw
Tooth ripple produces modulated signal by pmw comparator.
Above-mentioned dimming driving circuit, dimming unit includes being connected between described output node and this floating ground reference potential
First diode and first, second resistance, the anode of the first diode is connected to described output node and first, second resistance
It is connected between the negative electrode of the first diode and this floating ground reference potential；Also include being series at both first, second resistance mutually
The second diode between the first end of a common node at even and described first electric capacity and 3rd resistor, and include and second
It is described flat that one the second electric capacity of resistor coupled in parallel, the first end of the wherein second electric capacity and the negative electrode of the second diode are connected to offer
The described common node of equal magnitude of voltage, and 3rd resistor is connected to the anode of described second diode and the first end of the first electric capacity
Between, the second end of first, second electric capacity is configured to connect to this floating ground reference potential.
Above-mentioned dimming driving circuit, dimming unit includes being connected between described output node and this floating ground reference potential
First diode and first, second resistance, the anode of the first diode is connected to described output node and first, second resistance
It is connected between the negative electrode of the first diode and this floating ground reference potential；Carrying at the interconnection of both described first, second resistance
Common node for described average voltage level is coupled in the first end of described first electric capacity, and the second end of described first electric capacity is joined
It is set to and be connected to this floating ground reference potential.
Above-mentioned dimming driving circuit, when the forward conduction voltage sum convergence of described average voltage level and described second diode
When equal to described integral voltage, described dimming unit lost efficacy；When the angle of flow of controllable silicon dimmer change alternating current is extremely described
The voltage that the forward conduction voltage sum of average voltage level and described second diode is exported less than error amplifier output
When, the second diode between described common node of the first end of the first electric capacity and 3rd resistor form current path, thus
Described integral voltage is dragged down by this path.
Above-mentioned dimming driving circuit, directly to clamp down on described integral voltage by described average voltage level so that described integration
The variable quantity of voltage is consistent with the variable quantity of described average voltage level, thus being consistent with the variation tendency of the angle of flow
Described average voltage level directly changes the dutycycle of described modulated signal.
Above-mentioned dimming driving circuit, described electric pressure converter is configured with the reference potential phase on the spot of and described input voltage
With ground reference, make described switching tube when being driven by described modulated signal described modulated signal be with this reference potential on the spot
It is with reference to ground, then the described input voltage up-sampling that described dimming unit is received in described electric pressure converter captures described input
The average voltage level of voltage；The error voltage that in described control module, error amplifier is exported is on first electric capacity
Produce integral voltage, wherein this error amplifier is relatively and to amplify a reference voltage big with the electric current that a sign flows through load
Difference between little feedback voltage, described dimming unit, when the angle of flow reduces and causes described average voltage level to reduce, drags down
Described integral voltage simultaneously forces the dutycycle of described modulated signal to reduce.
Above-mentioned dimming driving circuit, dimming unit include being connected on described input voltage and on the spot between reference potential first
Diode and first, second resistance, the anode of the first diode is connected to described input voltage and first, second resistant series
In the negative electrode of the first diode with the spot between reference potential；It is series at first, second resistance interconnection with inclusion
The second diode between the first end of individual common node and described first electric capacity and 3rd resistor, and include with second resistance simultaneously
One the second electric capacity of connection, the first end of described second electric capacity is connected to the described common node providing described average voltage level,
Wherein respective second end of this first, second electric capacity is connected to reference potential on the spot.
Above-mentioned dimming driving circuit, the anode of the second diode is connected to the first end of the first electric capacity, the moon of the second diode
It is connected with described 3rd resistor between pole and described common node；Or second the cathode terminal of diode be connected to described public section
Point, and between the first end of the anode tap of the second diode and the first electric capacity, it is connected with described 3rd resistor.
Above-mentioned dimming driving circuit, dimming unit include being connected on described input voltage and on the spot between reference potential first
Diode and first, second resistance, the anode of the first diode is connected to described input voltage and first, second resistant series
In the negative electrode of the first diode with the spot between reference potential；And being used at interconnection both described first, second resistance carries
A common node for described average voltage level is coupled in the first end of described first electric capacity, and described first electric capacity
Second end is connected to reference potential on the spot.
Above-mentioned dimming driving circuit, when the forward conduction voltage sum convergence of described average voltage level and described second diode
When equal to described integral voltage, described dimming unit lost efficacy；When the angle of flow of controllable silicon dimmer change alternating current is extremely described
The voltage that the forward conduction voltage sum of average voltage level and described second diode is exported less than error amplifier output
When, the second diode between described common node of the first end of the first electric capacity and 3rd resistor form current path, thus
Described integral voltage is dragged down by this path.
Above-mentioned dimming driving circuit, directly clamps down on described integral voltage by described average voltage level so that described integration is electric
The variable quantity of pressure is consistent with the variable quantity of described average voltage level, thus the institute being consistent with the variation tendency of the angle of flow
State the dutycycle that average voltage level directly can change described modulated signal.
Above-mentioned dimming driving circuit, the described integral voltage of integrated generation and a saw at the first end of described first electric capacity
Tooth ripple is compared by control module pwm comparator, produces described modulated signal using this comparator.
Brief description
Read described further below and with reference to after the following drawings, the feature of the present invention and advantage will be evident that:
Fig. 1 a is the basic circuit Organization Chart of traditional triac dimmer.
Fig. 1 b is the original ac power waveform inputing to triac dimmer.
Fig. 1 c is the sine wave of alternating current by the waveform after triac dimmer cut parallactic angle.
Fig. 2 be the present invention based on the output voltage sampling of electric pressure converter is realized make the dutycycle of pwm modulated signal with
The change of conductance for alternating current current flow angle and the schematic diagram of the dimming driving circuit of linear change.
Fig. 3 is a kind of example producing pwm modulated signal.
Fig. 4 is a kind of dimming unit that the present invention illustrates taking the buck type electric pressure converter of floating ground framework as a example.
Fig. 5 is a kind of simplification dimming unit that the present invention illustrates taking the buck type electric pressure converter of floating ground framework as a example.
Fig. 6 be the present invention based on the input voltage sampling of electric pressure converter is realized make the dutycycle of pwm modulated signal with
The change of conductance for alternating current current flow angle and the schematic diagram of the dimming driving circuit of linear change.
Fig. 7 is a kind of dimming unit that the present invention illustrates taking the flyback electric pressure converter of framework on the spot as a example.
Fig. 8 is a kind of dimming unit that the present invention illustrates taking the buck-boost type electric pressure converter of framework on the spot as a example.
Fig. 9 is a kind of dimming unit that the present invention illustrates taking the buck type electric pressure converter of framework on the spot as a example.
Specific embodiment
Below in conjunction with each embodiment, technical scheme is carried out with clearly complete elaboration, but described embodiment
It is only the present invention with being described herein explanation embodiment used and not all embodiment, based on the embodiment such as this, the skill of this area
The scheme that art personnel are obtained on the premise of not making creative work broadly falls into protection scope of the present invention.
It is applied to the bidirectional triode thyristor in the industry cycle commonly known as triac that the dimmer of lighting field is commonly used, be mainly run
Switch (tri-electrode ac switch) for three-pole AC, its common terminology is referred to as bidirectional thyristor or two-way
Reverse-blocking tetrode thyristor.Referring to Fig. 1 a, in controllable silicon dimmer, as long as the coordination electrode in bidirectional triode thyristor triac applies
Suitable trigger pulse, the alternating current v no matter being inputted in input line 101,102acPositive half cycle or negative half period,
Bidirectional triode thyristor triac is all triggered conducting.Elaborate this mode of operation of dimmer hereinafter, dimmer has defeated
Enter to hold p1With input p2And there is the output end p connecting load3And output end p4, it is connected on input p1(i.e. defeated
Enter line 102) and output end p3Between protective resistance rw1, adjustable resistance rw2With electric capacity cwConstitute phase-shifting trigger net
Network, two other port at the non-controlling end of bidirectional triode thyristor triac is connected to input p1And output end p3On
So that triac and this phase-shifting trigger network are in parallel, and electric capacity cwOne end and bidirectional triode thyristor triac control
It is connected with a bidirectional trigger diode diac, electric capacity c between electrode processedwThe other end be then coupled to triac two end
On one of mouth.The working method of triac is embodied in, and is transferred to alternating current in input line 101,102 just half
Weekly assembly is to electric capacity cwCharge, once electric capacity cwThe voltage of one end accumulation being connected with bidirectional trigger diode diac is risen
To bidirectional trigger diode diac forward blocking voltage when, bidirectional trigger diode diac will breakdown turn on, and
Bidirectional triode thyristor triac is made to be triggered conducting further, such that it is able in output end p3And p4Between for load provide electricity
Source.Equally, in negative half period, once electric capacity cwOn the voltage of one end accumulation being connected with bidirectional trigger diode diac
Be raised to bidirectional trigger diode diac reverse BV when, bidirectional trigger diode diac equally also can breakdown lead
Logical, the conducting further such that bidirectional triode thyristor triac is triggered.We pass through to adjust adjustable resistance rw2The size of resistance
Electric capacity c just can be changedwCharge constant, the voltage turn-on angle of bidirectional triode thyristor traic changes, also therewith
Change the electric current flowing through load, result makes the brightness of the load of luminescent device class with adjustable resistance rw2Regulation and become
Change.Triac light modulation is also known as phase dimming, and ultimate principle is the conduction angle by modulating triac, the friendship to input
Stream sine voltage vacCarry out copped wave, namely so-called cut, to reduce the virtual value of output voltage.Have in Fig. 1 b
Positive and negative amplitude vhvAC sine wave vacWaveform after a cut is embodied in Fig. 1 c.In any one positive half cycle
Or in negative half period, controlling angled a represents starts from scratch to the experienced phase angle of triggering bidirectional trigger diode diac conducting simultaneously
In the range of controlling angled a, triac is not turned on, and conduction angle then represents that triac starts the phase angle model of conducting that is triggered
Enclose, and triac can constant conduction (dash area representative in Fig. 1 c in the range of the conduction angle of positive half cycle or negative half period
vacThe voltage waveform of triac conducting is kept for after chopped), θ=π-α.If as term difference to reader
Bring the inconvenience in understanding, we define conduction angle in this application it is understood that just becoming in any one positive and negative half period
String wave voltage vacEffective angle of flow, the more at most conduction angle of phase angle corner cut is less.Although triac is in the industry cycle
There are many improved structures, but ultimate principle is all based on shown in Fig. 1 a-1c.
In fig. 2, in two buses namely a pair of input line 102,101 respective input p1、p2Between input by
The sinusoidal voltage v that civil power providesac, can be in the input p of an input line 1021And output end p3Between connect
One TRIAC dimmer 111 described above, sinusoidal voltage vacThrough this TRIAC dimmer 111
After carrying out expected conduction angle regulation, finally in one group of output end p of input line 102,1013、p4Between produce warp
Cross the copped wave after cut parallactic angle.This copped wave is transferred to the bridge rectifier 112 of next stage again, remains this copped wave of of ac
Input voltage v can be provided after bridge rectifier 112 rectificationin.It is emphasized that hereafter will introduce for providing
Input voltage v to electric pressure converter 113in, both can be pulsating volage with alternating component or by rectification
The output of device 112 utilizes the devices such as filter capacitor to filter off the DC quantity voltage of ripple.Therefore, should recognize when reading this paper
Know input voltage vinCan be substantially the of ac after rectification or DC quantity.
Referring to Fig. 2, electric pressure converter (voltage converter) 113 is exactly using the input voltage v being providedinProduce
Raw default average value current exports to load 114, and electric pressure converter 113 naturally also provides running voltage for load 114,
Only load 114 is to need constant current control during white light led.In one embodiment in FIG. 2, controlled by one
Module 115 is producing modulated signal spwm, such as pulse width modulating signal, is coupled in electric pressure converter 113 and is used for
The control end of the switching tube of power conversion.In electric pressure converter 113, main switch is generally connected with inductive element, and electric
The process of sensing unit energy storage is exactly the process flowing through its electric current from zero to stable state maximum, once switching tube is in conducting and disconnection
Between switching it is possible to determine input voltage vinWhether to the direct transmission energy of inductance element.Such as in switch periods,
Switching tube is switched on stage then input voltage v in electric pressure converter 113inForm current path and inductance element between and lead to
Electric current flows through inductance element and to inductance element transmission energy, and vice versa, once switching tube is closed, input voltage vin
Path cannot be formed and electric current can not be provided to inductance element and switching tube between, this stage is that inductance element releases energy on the contrary
Process, this continue in follow-up content introduce.In the handoff procedure of switching tube, a dimming unit 116
Need monitor in real time to the changing condition of conduction angle as the foundation adjusting pwm dutycycle, for example, can turn from voltage
Parallel operation 113 is used for providing output voltage voutOutput node at come this output voltage v that to sampleoutAn average voltage level
vsam, the voltage that this sampling obtains is as to alternating voltage vacOutput voltage after execution cut parallactic angle is carried out in real time
The result of detecting.And dimming unit 116 is exactly using average voltage level v of samplingsam, change in controllable silicon dimmer 111
Become alternating voltage vacWhile conduction angle, also make modulated signal spwmDutycycle duty ratio with conduction angle
Change and change, will be discussed in detail how the present invention realizes this point in subsequent content.
According to the safety standard standard of countries in the world or each department, such as ul, ce, ccc etc. all to electric equipment products power because
Number pfc has certain code requirement.Such as erp certification it is stipulated that power be less than or equal to 2w inactivity factors dictate,
But 2w to 5w then requires pf value to require to be more than 0.4, and 5w to 25w then requires pf value to be more than 0.5, exceedes
Bigger power 25w then requires pf value to be more than 0.9.For another example the codes and standards of Energy Star are proposed for more than 5w's
Led illuminating product is it is desirable to power factor index p fc have to be larger than 0.7.For led illumination, realize high pf value
Method needs to adopt capacitance compensation, makes control chip fix service time within a short period of time, improves the constant current of switching mode led
The power factor in source, the ultimate principle of this technology is as shown in Figure 3.Referring to Fig. 3, an error amplifier a2 is to outside
Signal is processed, the first electric capacity c1For compensating electric capacity, the first electric capacity c1The voltage of error amplifier a2 output is carried out
Integration, thus in the first electric capacity c1One integral voltage v of upper generationcomp, namely obtain average voltage.Integral voltage vcomp
With sawtooth waveforms vsloThrough pwm comparator a1 relatively after, obtain pulse width modulating signal spwm, for controlling electricity
Switching tube in pressure converter 113, forms loop.Wherein error amplifier a2, the loop response speed of comparator a1
Than the first electric capacity c1Electric discharge fireballing many, and amplifier a2 produce result need delay a period of time could
By vcompVoltage reflects, and the driving current of amplifier a2 is less, simultaneously error amplifier a1, comparator a
Relatively independent, so whether comparator a1 normal work is dependent only on vcompPlace's voltage.
Must be it is stressed that although control module 115 produces modulated signal spwmMode have a lot, but in order to
Illustrate present invention spirit, temporarily to describe explanation by the model simplifying in Fig. 3, but must declare, this
Plant the example that simplified model is merely possible to explain, but the present invention is not restricted to this specific model, those skilled in the art
Member is it will be appreciated that it can be substituted by any equivalents being proposed based on present invention spirit.
Shown in Figure 4, input voltage vinThe buck voltage inputing to a voltage-dropping type from input line 201,202 turns
Parallel operation, input line 202 has ground reference gnd1, and the input voltage v in input line 201inIt is with respect to ginseng
Examine the current potential that ground potential gnd1 (or claim on the spot, altogether and/or systematically etc.) has.Adopt for power conversion
One switching tube q1 can be for example the mosfet of nmos type, and the drain electrode end (input) of switching tube q1 is even
It is connected to input line 201, and be connected between the node n1 at source terminal (outfan) place and the first end of an inductance l1
One detection resistance rcs1, and between the node n2 at another second end of inductance l1 and ground reference gnd1
It is connected with output capacitance cout, another one fly-wheel diode dfw1Anode be connected to ground reference gnd1
And this fly-wheel diode dfw1Negative electrode be then connected to node n1, finally we produce at output node n2 desired
Output voltage voutIt is used for as led load 114 offer running voltage.One or more led loads 114 by concatenation
In the anode tap of initial first led be connected to output node n2, and last end in the led load 114 concatenating
The cathode terminal of one led is connected to ground reference gnd1.Current sample mode in Fig. 4 is: node n1 and electricity
It is connected with detection resistance r between the first end (there is a floating ground gnd2) of sense l1cs1, and monitor flow through this detection
Resistance rcs1The resistance of electric current and this resistance mutually can be converted into detection voltage v at conveniencecs.
In the diagram, blood pressure lowering buck electric pressure converter have configuration floating ground port gnd2 (floating gnd) and
And this Single port has a floating ground potential, such as detection resistance rcs1With there is at the first end interconnection of inductance l1 this floating ground
Current potential gnd2.The reference voltage of electric pressure converter itself uses chip ground or claims this floating ground gnd2, and inputs
Voltage vinUsing be then ground reference gnd1 namely systematically it is evident that both is different current potentials in fact.Especially
When it is to control the grid of power switch pipe q1 so that it is switched between two states turning on and off, the current potential on this two ground
It is different, so the embodiment of Fig. 4 is called a floating ground voltage-dropping type buck circuit, the topological structure of the type is very big
Simplify the making of transformator, reduce the volume of transformator, require also ratio relatively low the pressure voltage of mos switching tube q1,
Improve efficiency, this kind of framework is also natural simultaneously decreases ripple, makes output capacitance coutCan be with very little.
In the diagram, because sampled voltage vcsEssence can characterize or be converted to the electric current flowing through load, as long as we control
Make and limit sampled voltage vcsIt is equivalent to control the current value size flowing through load, and then exporting of producing is to loading
Default average value current just controlled, light emitting diode is current constant control, but the default average value current size in the present invention
Adjustable, this is applied to follow-up all embodiments.For controlling the sampled voltage v flowing through load 114 size of currentcsDefeated
Enter the first end such as normal phase input end to error amplifier a2, and a reference voltage vrefThen it is input to this error to put
The second end such as inverting input of big device a2.The sawtooth waveforms v that agitator (osc) 125 in Fig. 3 producessloInput
To the second end such as inverting input of pwm comparator a1, error amplifier a2 is in the first electric capacity c1Unearthed one end
The integral voltage v producing on node n3compIt is input to the first end such as normal phase input end of pwm comparator a1, thus
Pulse width modulating signal s is produced by pwm comparator a1pwm, for driving switch pipe q1.Dimming unit 116 wraps
Include the first diode d1 being connected between output node n2 and floating ground gnd2 and first resistor r1, second resistance
R2, the anode tap of the wherein first diode d1 is connected to output node n2, and first resistor r1, second resistance r2 are then
It is connected between the cathode terminal of the first diode d1 and a floating ground gnd2.Wherein dimming unit 116 also includes the two or two
Pole pipe d2 and 3rd resistor r3, this second diode d2 and 3rd resistor r3 are series at first resistor r1, the second electricity
A common node n4 at resistance both r2 interconnection and the first electric capacity c1Between a unearthed end node n3, and dim
Unit 116 also has a second electric capacity c2, the second electric capacity c2In parallel with second resistance r2.Second electric capacity c2One
The cathode terminal of end and the second diode d2 is all connected to provide average voltage level vsamCommon node n4 at, and the 3rd
Resistance r3 is connected to anode tap and the first electric capacity c of the second diode d21Between the node n3 of one end, the first electric capacity
c1, the second electric capacity c2Opposite other end be connected to a floating ground gnd2.
Due to being a floating ground buck circuit framework, the chip ground of electric pressure converter namely this floating ground gnd2 (for example configure
Be gnd2 at the first end of this inductance l1) and provide input voltage bus namely belong to ground reference on the spot
Gnd1 (for example configuration input line 202 is gnd1) is not same ground potential, and chip ground and systematically two ground
At any time all in change, so the sampled point capturing the change voltage of inductance l1 should be on the basis of this floating ground gnd2, hereafter
This point will be explained further in detail.The working mechanism of dimming unit 116 is embodied in, when dimming unit 116 is in normally
First working condition stage, to sine wave input voltage vacCut, can configure adjustment first resistor and the second electricity
The resistance of resistance r1, r2 is so that vsam+vth≈vcomp, this relational expression represents the voltage v of node n3compAbout etc.
Voltage v in node n4samPlus the forward conduction voltage drop v on the second diode d2th(sometimes diode is so-called
Forward conduction voltage is also referred to as threshold voltage).It is noted herein that, diode forward conduction voltage drop of different nature
vthAlso it is slightly different, the forward conduction voltage drop of such as silicon diode is about 0.7 volt about, and the conducting pressure of germanium diode
It is reduced to about 0.3 volt about, Schottky diode is then lower.This stage dimming unit 116 does not work, and flows through load
It is constant that 114 default average value current may be controlled near constant.
As input sine wave voltage vacWhen starting cut parallactic angle, dimming unit 116 entered for the second working condition stage,
This stage, comparator a1 was affected by two loops, and first loop is through buck circuit, the node n2 of sampling, rectification
Average voltage level v of samplingsam, integral voltage vcomp, comparator a1, again via modulated signal spwmFeed back to buck
The electric current of electric pressure converter, in first loop, the energy that sampling node n2 obtains starts to reduce, long-pending at node n4
Discharge cycle is divided to obtain average voltage level vsamStart to reduce.Second loop is that control module 115 detects and flows through load
114 electric current namely sampled voltage vcsStart to reduce, comparator a1 and error amplifier a2 loop can make great efforts to make pwm
Dutycycle increase it is intended to allow the output current flowing through load 114 recover normal, the consequence that this loop produces makes node
Integral voltage v at n3compRise, thus produce voltage difference.It is easy to learn, integral voltage v at node n3comp
Voltage is subject to two loop combined influences, once the electric current of error amplifier a2 output increases, but due to long-pending at node n3
Component voltage vcompGo out average voltage level v with node n4samBetween there is the voltage difference that can not be ignored, this section can be made immediately
Integral voltage v at point n3compElectricity declines.On the one hand, input sine wave vacIt is notched i.e. conduction angle reduction to lead to
Input voltage vinVirtual value reduce, and on the other hand, modulated signal s of controlling switch pipe q1pwmDutycycle but
Can not increase, so the average current finally exporting to load 114 is naturally reduced by and reaches dimming effect.
Dimming unit 116 is in the second working condition stage (input sine wave vacIt is notched) specific works pattern is hereafter
To illustrate one by one.In the diagram, it is connected to a resistance r4 between node n3 and the outfan of error amplifier a2
For the resistance of chip internal, such as resistance r4 is the parasitism/intrinsic output resistance of error amplifier a2, its resistance value phase
Much greater for 3rd resistor r3.Sine voltage vacCut away after a part of angle by controllable silicon dimmer 111,
In order to maintain constant current, second loop being mentioned above can attempt to force the integral voltage v at n3 nodecomp
Lifting, this is essentially due to the error voltage v that error amplifier a2 outfan is exportedeaIncrease is induced.Simultaneously
Due to sine voltage vacThe current potential leading to sampling node n2 after being cut off a part of angle reduces, and here to output electricity
Pressure voutAverage voltage level v of samplingsam(at node n4) is the voltage that inductance l1 discharge portion is integrated, and puts down
All magnitude of voltage vsamVariation tendency consistent with the variation tendency of the conduction angle of alternating current, that is, synchronous increase or reduce,
V can be made eventuallyea＞ vsam- vth, vthIt is forward conduction voltage drop or the threshold voltage of the second diode d2.Then now the 3rd
Have electric current to pass through between the output resistance r4 of resistance r3 and error amplifier a2, but again due to the first electric capacity c1 and
The presence of the second electric capacity c2, so this stage average voltage level vsam(at node n4) and integral voltage vcomp(section
At point n3) in fact it is close to direct current that is to say, that whole circuit attempts integral voltage vcompIt is fixed on one to preset
Voltage, so this modulated signal spwmTend to being generally fixed in whole power frequency.
But the voltage v that error amplifier a2 outfan is exportedeaIncrease, by average voltage level v of samplingsam(section
At point n4) and error amplifier a2 outfan voltage veaBetween voltage difference, through the second diode d2 and
Path of releasing between three resistance r3 and resistance r4 can change integral voltage vcompThe value of (at node n3), integration
Voltage vcompChange be equivalent to and make sawtooth waveforms vsloWith integral voltage vcompIntersection point occur in advance, so master switch
The ON time of pipe q1 can shorten, so that modulated signal spwmDutycycle or the cycle reduce.
vcomp=vsam+vth+(vea-vsam-vth)×r3/(r3+r4)……(1)
vcomp=vth+(vea×r3+vsam×r4-vth×r3)/(r3+r4)……(2)
The physical meaning that functional relation (1) characterizes represents the voltage v of node n3compDeduct the second diode d2's
Forward conduction voltage drop vthWith the voltage v deducting node n4samDifference after, can obtain flowing through divided by resistance r3
The electric current of three resistance r3, and this electric current is simultaneously equal to flow through the electric current of 3rd resistor r3 and resistance r4.Voltage vea
Deduct the forward conduction voltage drop v of the second diode d2thWith the voltage v deducting node n4samDifference after, then divided by
Resistance (r3+r4) is exactly the electric current flowing through 3rd resistor r3 and resistance r4.Relational expression (2) is relational expression (1)
Equivalent deformation form, will v on the right side of functional relation (1) equationsamFirst it is multiplied by (a r3+r4) again divided by one
Individual (r3+r4) after, make merging similar terms on the right side of equation can obtain functional relation (2).
In functional relation (1) and (2), r3 and r4 represents 3rd resistor r3 and the respective resistance of resistance r4 respectively,
Parasitism/intrinsic output resistance that resistance r4 be error amplifier a2 has been mentioned above, its resistance value r4 is relative to the 3rd
Resistance r3 is much greater, furthermore voltage vsamRate of change also be far above voltage veaRate of change, then vsam×r4
Rate of change be much larger than vea× r3, as long as so we reasonably to configure resistance value r1, r2, r3 and r4 just permissible
Dispense v from the molecule of functional relation (2)ea× r3 this so that voltage vcompIt is similar to and node n4
The voltage v at placesamHolding linear variability law.In other words, as input sine wave vacDuring by cut parallactic angle, can lead to
The voltage v of sampling at node n2samReduce, further such that the voltage v at node n4samFollow voltage vsam
Linear reduction, thus ultimately result in modulated signal spwmDutycycle or the cycle with voltage vsamLinear reduction, that
The ON time of switching tube q1 reduced within the cycle, so that the energy flowing to inductance l1 also can be reduced in discharge regime, stream
The default average value current of overload 114 reduces and directly causes led luminous intensity to weaken.
As long as sum it up, the change that is notched with sine wave of the average voltage of whole buck circuit sampled point n2 and line
Property change it is possible to make the voltage v at node n3compThe change size that is notched also with sine wave and linear change,
And can achieve s furtherpwmThe dutycycle of waveform with the change being notched linear change it is seen then that the present invention obtain
This etc. advantage have the usual skill in this area found pleasure in see its one-tenth.
The embodiment of Fig. 4 is relatively can the changing control module 115 by dimming unit 116 and export of more accurate calculating
Modulated signal spwmMethod, but in the drive scheme that required precision is not very high, can also the light modulation shown in from Fig. 4
The second diode d2 and the second electric capacity c is dispensed in unit 1162And 3rd resistor r3, so the embodiment of Fig. 5 is relatively
Fig. 4 embodiment it is simply that eliminating this three components and parts, others are then and zero difference.Now dimming unit 116 wraps
Include and be connected on the first diode d1 and first, second resistance r1, r2 that output node n2 and floats between ground gnd2,
The anode tap of the first diode d1 is connected to output node n2, and first resistor r1, second resistance r2 are connected in series in
Between the cathode terminal of the first diode d1 and a floating ground gnd2, at first resistor r1, the interconnection of both second resistances r2
Offer average voltage level vsamA common node n4 be coupled on an end node n3 of the first electric capacity c1, first
The other end of electric capacity c1 is connected on a floating ground gnd2.Because node n3 is directly coupled to node n4, realize by
Average voltage level v of node n4samDirectly clamp down on the integral voltage v of node n3comp, integral voltage vcompChange
Amount followed by the output voltage v capturing in output node n2 samplingoutAverage voltage level vsamVariable quantity, with leading
The change of current flow angle θ and average voltage level v that changessamDirectly change modulated signal spwmDutycycle, such as corner cut diminishes
And conduction angle slightly increases then average voltage level vsamWith integral voltage vcompAll slightly increase, or corner cut become big and
Conduction angle is slightly reduced then average voltage level vsamWith integral voltage vcompAll slightly reduce.So the enforcement in Fig. 5
Also substantially can realize the expected dimming function of embodiment 4 in example, if in buck circuit sampled point n2 voltage with
Sine wave to be notched and linear change is so that it may make the voltage v at node n3compWith the size being notched by sine wave
And linear change, realize s furtherpwmThe dutycycle of waveform linear change with the change being notched, because this grade is adjusted
Light measure has hereinbefore been discussed in detail, so it will not go into details.
Must state, the topological structure being used as example in Fig. 4-5 is used for the purpose of the reader widely to the application
Prove universal meaning in the scope of application of electric pressure converter for the present invention spirit, but do not constitute any specific restriction, they
Can be taken by any other various applicable topologys converting to substitute.
Be described above buck float ground, chip ground and bus ground be not same current potential, chip ground and busbar voltage
Change at any time, be explained in more detail as the source potential of this mos switching tube q1 (drives the drive of mos pipe
The actual reference ground of dynamic signal) can be with diode dfw1Conducting and cut-off and there is about-vthWith+vinSo
The change shake of amplitude, v herethIt is diode dfw1Forward conduction voltage but vinInput voltage, so make
The driving of switching tube q1 modulated signal and when switching between conducting and shutoff this modulated signal be with this floating ground reference
Current potential gnd2 is actual with reference to ground.Possibly the voltage after cut parallactic angle cannot be carried out in view of directly sampling on bus
Reaction feedback in real time, so sampled point n2 becomes and output voltage voutFeeder ear is identical, and sampling obtains coming independently electricity
Sense l1 simultaneously obtains average voltage v through the first diode d1 rectificationsam.When controllable silicon triac dimmer just cuts away
String ripple vacA part of angle after, main inductance l1 storage energy ratio normal work when energy reduce, inductance l1 two
End average voltage can reduce, the average voltage v obtaining after rectifying and wave-filteringsamAlso can reduce, lead on the first electric capacity c1
Integral voltage vcompReduce, but because the original function of control module itself thinks vcompNeed to rise, or frequency needs
Change, but external drive ability is greater than internal drive ability so v at node n3compValue determined by outside,
And force to make integral voltage vcompMagnitude of voltage accordingly reduce.In the same manner, dimming function is realized also by above circuit
The topological situation at some non-floating (non-floating gnd) can be applied, the follow-up ensuing disclosure of the present invention will be situated between
Continue (nfg) circuit non-floatingly of flyback and buck-boost and traditional buck, due to non-floating (nfg)
Chip ground be systematically a ground, can directly up-sample in bus.Fig. 6 is substantially similar with Fig. 2, but voltage
Transducer 113 is (nfg) type non-floatingly, so dimming unit is no longer from output voltage v beforeoutEnd acquisition is adopted
Sample voltage, then from offer input voltage vinBus on capture sampled voltage.In addition, the ensuing disclosure of the present invention
The common or uncommon power conversion spreading apart based on the spirit of Fig. 6 will be introduced corresponding to Fig. 7-Fig. 9 one by one
Topology, proves general applicability in electric pressure converter for the dimming unit providing according to present invention spirit further.
In the flyback voltage transducer of Fig. 7, sinusoidal input AC electricity vacConduction angle is adjusted by controllable silicon dimmer 111,
Sine wave alternating current v through cut parallactic angleacAfter bridge rectifier 112 rectification, to the transformation of flyback voltage transducer
Device t provides input voltage vin.Notice that in the present embodiment, dimming unit 116 is in input voltage vinUp-sampling captures this input
Voltage vinAverage voltage level vsamWhen, the input voltage v on businBoth can be carrying of commutator 112 output
Through input capacitance c after the pulsating volage of alternating component or commutator 112 outputinIt is presented as direct current after filtering
The input voltage v of amountin.The armature winding of flyback voltage transducer is in switching tube q2 conducting phase storage energy in switch
Pipe q2 off-phases transmit energy to secondary windings.The armature winding of switching tube q2 and transformator and detection resistance rcs2
It is connected on input voltage vinAnd between for ground reference gnd1 on the spot, the drain electrode end (input) of switching tube q2
Connect one end of armature winding, the other end receives input voltage v of armature windingin, and the source in this main switch q2
Extremely (outfan) is connected with this detection resistance r and ground reference gnd1 betweencs2.And a termination of secondary windings
Gnd1 and its other end pass through a commutation diode d on the spotrecOutput node at the negative electrode of diode provides defeated
Go out voltage vout, output capacitance coutIt is connected on the spot between gnd1 and this output node.In this output node
Place is led load 114 offer running voltage, by initial first led in one or more led loads 114 of concatenation
Anode tap be connected to output node, and the cathode terminal of a led at end and reference ground in the led load 114 concatenating
Current potential gnd1 is connected.When dimming unit 116 is in the normal first working condition stage, electricity need not be inputted to sine wave
Pressure vacCarry out cut parallactic angle, and now v can be made with the resistance of configuration adjustment first resistor and second resistance r1, r2sam
+vth≈vcomp, namely the voltage v representing node n3compApproximate the v of node n4samAlong with one second
The forward conduction voltage drop v of diode d2th, this stage dimming unit 116 do not work.
As input sine wave voltage vacWhen starting cut parallactic angle, dimming unit 116 entered for the second working condition stage,
This stage, comparator a1 was affected by two loops, and first loop is the input voltage v of samplinginIt is flat that place, rectification are sampled
All magnitude of voltage vsam, integral voltage vcomp, comparator a1, again via modulated signal spwmFeed back to flyback voltage to turn
The electric current of parallel operation.In first loop, from input voltage vinThe energy obtaining starts to reduce, and is put down at node n4
All magnitude of voltage vsamStart to reduce.Second loop is, detection resistance rcs2On sampled voltage vcsIt is input to error to amplify
The second end such as inverting input of device a2, a reference voltage vrefThen it is input to the first end of this error amplifier a2 such as
Normal phase input end.The sawtooth waveforms v that agitator 125 produces simultaneouslysloThe first end being connected to pwm comparator a1 is as just
Phase input, error amplifier a2 is in the first electric capacity c1The integral voltage v producing on a unearthed end node n3comp
It is input to the second end such as inverting input of pwm comparator a1.In some optional but nonessential embodiments, in fact
Can also be using the inversion signal of pwm comparator a1 output result as modulated signal.If control module 115 detects
Sampled voltage vcsPeak value reduce, namely flow through load 114 average current reduce, then the first electric capacity at node n3
The integral voltage v of c1compAttempt to increase to adjust to raise and flow through armature winding, switching tube q2 and detection resistance rcs2
Peak point current, that is, increase controlling switch pipe q2 modulated signal dutycycle.Although integral voltage vcompAttempt increases,
But due to integral voltage v at node n3compMore than average voltage level v at node n4samPlus the second diode d2
Conduction voltage drop vth, integral voltage v at node n3 can be made immediatelycompIt is pulled low.On the one hand, due to the sine of input
Wave voltage vacInput voltage v is led to by cut parallactic angleinVirtual value and sampling average voltage level vsamReduce, lead
The peak point current causing primary side reduces, so the default average value current flowing through load 114 also can decline；On the other hand,
But due also to modulated signal is used to drive nmos switching tube q2 modulated signal spwmDutycycle but cannot increase,
So the average current exporting to load 114 is reduced by and reaches dimming effect.
Shown in Figure 7, dimming unit 116 includes being connected on input voltage vinBetween gnd1 the one or two on the spot
Pole pipe d1 and first resistor r1, second resistance r2, the anode tap of the first diode d1 is connected on input voltage vin,
And first resistor r1, second resistance r2 are connected on the cathode terminal of the first diode d1 and on the spot between gnd1.Also set
The second diode d2 being equipped with and 3rd resistor r3, the second diode d2 and 3rd resistor r3 are series at first resistor
Between a common node n4 at r1, the interconnection of both second resistances r2 and the first electric capacity c1 mono- end node n3, with
And also including in parallel with second resistance r2 the second electric capacity c2, one end of the second electric capacity c2 is connected to offer
Average voltage level vsamCommon node n4, the respective other end of the first electric capacity c1 and the second electric capacity c2 is configured to even
It is connected to gnd1 on the spot.In view of the position of the second diode d2 and 3rd resistor r3 can be exchanged, so there are two kinds of feelings
Condition: the anode tap of the second diode d2 is connected to the unearthed end node n3 of the first electric capacity c1, the second diode d2
Cathode terminal and common node n4 between be connected with 3rd resistor r3 (Fig. 7)；Or the cathode terminal of the second diode d2
Be connected to common node n4, and the anode tap of the second diode d2 and the unearthed end node n3 of the first electric capacity c1 it
Between be connected with 3rd resistor r3 (in figure does not illustrate).In the second working condition stage of dimming unit 116, (input is just
String ripple vacIt is notched), input sine wave voltage vacCut away after a part of angle by controllable silicon dimmer 111, in order to tie up
Hold constant current, loop can attempt to promote the integral voltage v at n3 nodecompLifting.But due to sine voltage vac
Sampling node input voltage v is then led to after being cut off a part of angleinCurrent potential reduce, be equivalent to the source in switching tube q2
Pole and detection resistance rcs2At interconnection, the current signal of sampling reduces, and the mistake that error amplifier a2 outfan is exported
Potential difference veaIncrease, finally by average voltage level v of samplingsam(at node n4) and error amplifier a2 export
The voltage v at endeaBetween voltage difference, produce through the second diode d2 and 3rd resistor r3 path of releasing, this meeting
Change integral voltage vcompThe value of (at node n3) simultaneously promotes its reduction, leads to the modulated signal of driving switch pipe q2
Dutycycle reduce so that ON time within the cycle for the switching tube q2 shortens.
The embodiment of Fig. 8 and Fig. 7 are substantially similar, and only range of application is no longer flyback voltage transducer mentioned above,
But the electric pressure converter of buck buck-boost type, note the output electricity of the output node of buck-boost topology
Pressure polarity is contrary than input voltage.The first end of one inductance l2 is connected to a node n5, and inductance l2
It is connected with a fly-wheel diode d between another second end and a node n6fw2, fly-wheel diode dfw2Anode even
It is connected to second end of inductance l2, and fly-wheel diode dfw2Negative electrode be connected to node n6, output capacitance cout
It is connected between node n5 and n6, fly-wheel diode dfw2, inductance l2 be also connected between node n5 and n6,
Output capacitance coutWith diode dfw2, both inductance l2 in parallel.One or more led loads 114 by concatenation
In be connected detection resistance r between the initial anode tap of first led and output node n6cs3, and the led concatenating
In load 114, the cathode terminal of a led at end is connected to node n5.The drain electrode of one main switch q3 is connected to electricity
Second end of sense l2 and fly-wheel diode dfw2Anode interconnection node location, and the source electrode of switching tube q3 then with input
Voltage vinGround reference gnd1 between be connected with an inductive reactance rs.One current sense amplifier a3's
Positive input terminal is connected to node n6, and its negative input end is connected to detection resistance rcs3With the led load 114 concatenating
In first led anode tap interconnection at node, thus current sense amplifier a3 is used for detecting flows through load 114
Electric current is simultaneously presented as the sampled voltage v that this amplifier a3 outfan exportscs(for electric current and resistance rcs3Product).One
The positive input terminal of individual current sense amplifier a4 is connected to inductive reactance rsInterconnect and between the source electrode of nmos switching tube q3
Node, the negative input end of current sense amplifier a4 is connected to ground reference gnd1, this current sense amplifier
A4 flows through inductive reactance r for detectingsOn current signal.The circuit of dimming unit 116 is identical with Fig. 7 and no longer heavy
Repeat again, wherein error amplifier a2 outfan is connected at the unearthed end node n3 of the first electric capacity c1, detection
Resistance rcs3On the sampled voltage v feeding backcsIt is input to the second end such as inverting input of error amplifier a2,
One reference voltage vrefThen it is input to the first end such as normal phase input end of this error amplifier a2.As option, electricity
Stream detects the sawtooth waveforms v that the output result of amplifier a4 and agitator (osc) producesloSuperposition is input to pwm after compensating
The first end of comparator a1 such as normal phase input end, and error amplifier a2 is in the first electric capacity c1A unearthed end node
The integral voltage v that n3 producescompIt is input to the second end such as inverting input of comparator a1.
Referring to Fig. 8, input voltage vinInput to node n5, in switching tube q3 conducting phase, inductance l2 stored energy,
Electric current is via inductance l2, switching tube q3 and inductive reactance rsFlow to reference ground gnd1.And close faulted-stage in switching tube q3
Section, inductance l2 releases energy, and electric current is via fly-wheel diode dfw2And flow through detection resistance rcs3Bear with the led of series connection
Carry 114.When the driving of the modulated signal of switching tube q3 switches between conducting and shutoff, modulated signal is with this on the spot
Reference potential gnd1 be actual with reference to ground, chip ground with systematically consistent, this as Fig. 9 hereafter, so wherein
The anode of the first diode d1 in dimming unit 116 is connected to node n5, and being equivalent to dimming unit 116 can be direct
Input voltage v is being providedinBus up-sampling.
Referring to Fig. 8, if control module 115 detects flows through load 114 electric current namely the sampled voltage v of conversioncs
Start reduce, then at node n3 the first electric capacity c1 integral voltage vcompAttempt to increase to adjust raise flow through inductance l2,
Switching tube q3 and inductive reactance rsPeak point current, namely tend to increase controlling switch pipe q3 modulated signal duty
Than.But due to integral voltage v at node n3compGo out average voltage level v with node n4samBetween there is voltage difference,
The path of releasing producing can make integral voltage v at node n3compDecline.On the one hand, input sine wave vacIt is notched and lead
Cause input voltage vinVirtual value and magnitude of voltage vsamReduce, on the other hand, modulated signal s of controlling switch pipe q2pwm
Dutycycle cannot increase, then export the average current to load 114 and be reduced by and reach dimming effect.
The embodiment of Fig. 9 and Fig. 8 is substantially similar, and only range of application is no longer the electricity of buck buck-boost type
Pressure converter, but blood pressure lowering buck electric pressure converter.One of fly-wheel diode dfw3It is connected on one with inductance l3
Between node n7 and a node n8, fly-wheel diode dfw3Negative electrode be connected to node n7, and fly-wheel diode
dfw3Anode tap and node n8 between be connected with an inductance l3, wherein the first end of inductance l3 connects fly-wheel diode
dfw3Anode and second end connecting node n8 of inductance l3.Will be initial in one or more led loads 114 of concatenation
The anode tap of first led link together with node n7, and one of end in the led load 114 concatenating
The cathode terminal of led is connected to node n8.The drain electrode of one nmos switching tube q4 be connected to the first end of inductance l3 with
Fly-wheel diode dfw3Anode interconnection node location, and the source terminal of switching tube q4 then with input voltage vinGinseng
Examine and between ground potential gnd1, be connected with detection resistance rcs4.Blood pressure lowering its operation principle of buck electric pressure converter is,
Input voltage v after rectificationinInput to node n7, during switching tube q4 conducting, electric current flows through the led load 114 of series connection
With inductance l3 and switching tube q4 and detection resistance rcs4Flow to reference ground gnd1, inductance l3 stored energy, and opening
Close pipe q4 off-phases inductance l3 to release energy, the electric current flowing through inductance l3 is via fly-wheel diode dfw3Flow direction series connection
Led load 114 arrive node n8.So the anode of the first diode d1 wherein in dimming unit 116 is connected to section
Point n7, being equivalent to dimming unit 116 directly can provide input voltage vinBus up-sampling.
Error amplifier a2 outfan is connected at the unearthed end node n3 of the first electric capacity c1, in inductive reactance rcs4
Detection voltage v with sampling at the source terminal interconnection of switching tube q4csThe second end being input to error amplifier a2 is for example anti-phase
Input, a reference voltage vrefThen it is input to the first end such as normal phase input end of this error amplifier a2.Table simultaneously
It is now triangular wave or sawtooth waveforms vsloIt is input to the first end such as normal phase input end of pwm comparator a1, error amplifier
A2 is in the first electric capacity c1The integral voltage v that a unearthed end node n3 producescompIt is input to the second of comparator a1
End such as inverting input.Modulated signal s that the outfan of pwm comparator a1 is producedpwmDriving switch pipe q4's
Grid control end g.If control module 115 detects flows through load 114 electric current namely detection resistance r of samplingcs4
Start reduce, then at node n3 the first electric capacity c1 integral voltage vcompWill adaptive attempt to increase controlling switch
The dutycycle of the modulated signal of pipe q4, namely tend to raising and flow through load 114, inductance l3, switching tube q4 and faradism
Resistance rcs4Peak point current.But in feedforward light modulation action, to sine wave input AC electricity vacExecution cut parallactic angle it
The magnitude of voltage v of sampling can be dragged down afterwardssam, and due to integral voltage v at node n3compWith the average voltage at node n4
Value vsamBetween there is voltage difference, integral voltage v at node n3 can be made immediatelycompDecline.So input sine wave vac
Input voltage v is led to by cut parallactic angleinVirtual value and magnitude of voltage vsamReduce, and the modulation of controlling switch pipe q4
Signal spwmDutycycle cannot increase, the collective effect of these two aspects all can allow output default to led load 114
Average current reduces and reaches expected dimming effect.
In the embodiment of Fig. 7-9, input voltage vinBe rectified after voltage, due to bus and chip be same
Ground, then we can be with the meansigma methodss of voltage on direct detection bus, when bus is after controllable silicon triac, the having of voltage
Valid value can reduce, and filter through the second electric capacity c2, can get the average voltage of bus, the angle cut as controllable silicon triac
When degree is bigger, the voltage on the second electric capacity c2 is less, and the electric current that 3rd resistor r3 flows through is bigger, vcomp's
Voltage is less, thus forcing dutycycle that is fixing or changing pwm modulated signal or cycle, equally can achieve high pf
Value also achieves the function of light modulation.Due to be sampling be bus ground, voltage is higher, so should be noted first resistor
The pressure voltage of r1, and 3rd resistor r3 and the second diode d2 position can exchange.The respective enforcement of Fig. 7-9 simultaneously
In example, dimming unit can also be replaced using the simplification version of the dimming unit 116 of similar Fig. 5, abandons the two or two pole
Pipe d2 and the second electric capacity c2And 3rd resistor r3.Node n3 is directly coupled to node n4, substantially by node
Average voltage level v of n4samClamp down on the integral voltage v of node n3comp, integral voltage vcompVariable quantity followed by
In output node n2/ or vinThe output voltage v that sampling capturesout/ or vinAverage voltage level vsamVariable quantity, with
Average voltage level v the change of conduction angle and changesamDirectly change modulated signal spwmDutycycle, same circuit
Simply enter voltage vinThe linear change being notched with sine wave is so that it may make the voltage v at node n3compWith quilt
Size that sine wave is notched and linear change, realize s furtherpwmThe dutycycle of waveform line with the change being notched
Property change, due to this etc. light modulation measure be hereinbefore discussed in detail, so it will not go into details.
The topological structure being used as example above is merely illustrative present invention spirit and does not constitute any specific restriction, existing
White light led type of drive species various, and consideration the application as space is limited can only take by force and several can explain this
The representative illustration of application basic ideas, so should be appreciated that for there is the usual skill in this area when reading this paper,
The topological structure of description here can be taken by other various applicable topologys of any conversion to substitute, and is reading herein or is managing
The essence of the present application spirit should be respected fully during solution the limited scope of claim.
More than, by explanation and accompanying drawing, give the exemplary embodiments of the ad hoc structure of specific embodiment, foregoing invention carries
Go out existing preferred embodiment, but these contents have been not intended as limiting to.For a person skilled in the art, in reading
State bright after, various changes and modifications undoubtedly will be evident that.Therefore, appending claims should be regarded as and covers this
Bright true intention and whole variations and modifications of scope.In Claims scope any and all scope of equal value with interior
Hold, be all considered as still belonging to the intent and scope of the invention.
Claims (13)
1. a kind of dimming driving circuit is it is characterised in that include:
Controllable silicon dimmer, adjusts the angle of flow of received alternating current；
Electric pressure converter, the input exporting and being provided after being rectified through described controllable silicon dimmer cut parallactic angle by alternating current
Voltage, produces default average value current and exports to load；
Control module, the modulated signal being produced by it, drive to switch between conducting and shutoff in described electric pressure converter and use
In determining whether the switching tube to described Load transportation voltage and/or electric current using described input voltage；
Dimming unit, the changing condition of the angle of flow of detecting alternating current, and make the dutycycle of described modulated signal with conducting
The size variation trend at angle and follow this trend change.
2. dimming driving circuit according to claim 1 is it is characterised in that described electric pressure converter is configured with and institute
The different floating ground reference potential of reference potential on the spot stating input voltage is so that described switching tube is driven by described modulated signal
Shi Suoshu modulated signal is to be with reference to ground with this floating ground reference potential, and described dimming unit is in described electric pressure converter
Voltage output node sample captures the average voltage level of described output voltage；Wherein
One of described control module error amplifier relatively and amplify a reference voltage with one flow through for control negative
Carry the difference between the sampled voltage of size of current, the error voltage that described error amplifier is exported is on first electric capacity
Produce integral voltage, described dimming unit, when the described angle of flow reduces and causes described average voltage level to reduce, drags down described long-pending
The dutycycle that component voltage forces described modulated signal with this reduces.
3. dimming driving circuit according to claim 2 it is characterised in that dimming unit include being connected on described defeated
The first diode between egress and this floating ground reference potential and first, second resistance, the anode of the first diode connects
In described output node first, second resistant series between the negative electrode of the first diode and this floating ground reference potential；
Also include being connected between a common node and the first end of the first electric capacity at the interconnection of both first, second resistance
Second diode and 3rd resistor, and include in parallel with second resistance second electric capacity, the first end of the wherein second electric capacity
It is both connected to for producing at the described common node of described average voltage level with the negative electrode of the second diode, and 3rd resistor is even
It is connected between anode and the first end of the first electric capacity of described second diode, and make the second end configuration of first, second electric capacity
Become to be connected to this floating ground reference potential.
4. dimming driving circuit according to claim 2 it is characterised in that dimming unit include being connected on described defeated
The first diode between egress and this floating ground reference potential and first, second resistance, the anode of the first diode connects
In described output node first, second resistant series between the negative electrode of the first diode and this floating ground reference potential；
One common node of the described average voltage level of offer at the interconnection of both described first, second resistance is coupled to described the
In the first end of one electric capacity, the second end of described first electric capacity is configured to connect to this floating ground reference potential.
5. dimming driving circuit according to claim 3 is it is characterised in that when described average voltage level and described the
To during equal to described integral voltage, described dimming unit lost efficacy the forward conduction voltage sum convergence of two diodes；
When controllable silicon dimmer changes the positive guide of the angle of flow of alternating current to described average voltage level and described second diode
During the voltage that energising pressure sum is exported less than error amplifier output, the first end of the first electric capacity is between this common node
The second diode and 3rd resistor formed current path, thus dragging down the described integral voltage of the first end of the first electric capacity.
6. dimming driving circuit according to claim 4 is it is characterised in that directly clamp by described average voltage level
Make described integral voltage, so that the variable quantity of described integral voltage and the variable quantity of described average voltage level is consistent, thus with
The described average voltage level that the variation tendency of the angle of flow is consistent directly changes the dutycycle of described modulated signal.
7. dimming driving circuit according to claim 1 is it is characterised in that described electric pressure converter is configured with one
With the identical ground reference of reference potential on the spot of described input voltage, make described switching tube by during described modulated signal driving
Described modulated signal be with this on the spot reference potential be with reference to ground, and described dimming unit received in described electric pressure converter
Described input voltage up-sampling capture the average voltage level of described input voltage；Wherein
The error voltage that in described control module, error amplifier is exported produces integral voltage on first electric capacity,
Wherein this error amplifier relatively and amplifies a reference voltage and a sampling electricity flowing through load current size for control
Difference between pressure, described dimming unit, when the angle of flow reduces and causes described average voltage level to reduce, drags down described integration electricity
Press and force the dutycycle of described modulated signal to reduce.
8. dimming driving circuit according to claim 7 it is characterised in that dimming unit include being connected on described defeated
Enter voltage and the first diode between reference potential and first, second resistance on the spot, the anode of the first diode receives described
Input voltage and first, second resistant series are in the negative electrode of the first diode with the spot between reference potential；
Also include being connected on a common node at the interconnection of both first, second resistance and described first electric capacity first end it
Between second diode and a 3rd resistor, and include in parallel with second resistance second electric capacity, described second
The first end of electric capacity is connected to the described common node providing described average voltage level, and first, second electric capacity respective the
Two ends are all connected to this reference potential on the spot.
9. dimming driving circuit according to claim 8 is it is characterised in that the anode of the second diode is connected to
The first end of one electric capacity, is connected with described 3rd resistor between the negative electrode of the second diode and described common node；Or
The cathode terminal of the second diode is connected to described common node, and the first of the anode tap of the second diode and the first electric capacity
It is connected with described 3rd resistor between end.
10. dimming driving circuit according to claim 7 it is characterised in that dimming unit include being connected on described
The first diode between input voltage and on the spot reference potential and first, second resistance, the anode of the first diode receives institute
State input voltage and first, second resistant series are in the negative electrode of the first diode with the spot between reference potential；And
One common node of the described average voltage level of offer at the interconnection of both described first, second resistance is coupled to described the
In the first end of one electric capacity, the second end of described first electric capacity is connected to reference potential on the spot.
11. dimming driving circuits according to claim 8 are it is characterised in that when described average voltage level and described
To during equal to described integral voltage, described dimming unit lost efficacy the forward conduction voltage sum convergence of the second diode；
When controllable silicon dimmer changes the positive guide of the angle of flow of alternating current to described average voltage level and described second diode
During the voltage that energising pressure sum is exported less than error amplifier output, the first end of the first electric capacity to described common node it
Between the second diode and 3rd resistor formed current path, thus dragging down the described integral voltage of the first end of the first electric capacity.
12. dimming driving circuits according to claim 10 are it is characterised in that direct by described average voltage level
Clamp down on described integral voltage, so that the variable quantity of described integral voltage and the variable quantity of described average voltage level is consistent, thus
The described average voltage level being consistent with the variation tendency of the angle of flow directly changes the dutycycle of described modulated signal.
13. dimming driving circuits according to claim 2 or 7 are it is characterised in that produce on described first electric capacity
Described integral voltage and a sawtooth waveforms be compared by a comparator, this comparator export described modulated signal.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107461622A (en) * | 2017-09-14 | 2017-12-12 | 浙江生辉照明有限公司 | induction type bulb |
| CN108834253A (en) * | 2018-05-14 | 2018-11-16 | 卫斌鹏 | LED with overvoltage protection drives energy-saving power supply |
| CN109819551A (en) * | 2019-02-22 | 2019-05-28 | 无锡安特源科技股份有限公司 | A kind of constant current light modulating device for LED light |
| CN112803748A (en) * | 2021-01-29 | 2021-05-14 | 上海瞻芯电子科技有限公司 | Fixed feedforward control method for power factor correction circuit |
| CN113811041A (en) * | 2020-06-16 | 2021-12-17 | 矽诚科技股份有限公司 | Light-emitting diode module with sleep mode and light-emitting diode lamp string |
| CN114189958A (en) * | 2021-11-01 | 2022-03-15 | 广州市浩洋电子股份有限公司 | Device for reducing low-brightness jitter of light source by using vibration suppression module and lamp |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101861016A (en) * | 2010-05-11 | 2010-10-13 | 南通中润照明电器有限公司 | Dimming switch power supply device of LED lamp |
| CN202050568U (en) * | 2011-03-31 | 2011-11-23 | 南京汉德森科技股份有限公司 | Light-emitting diode (LED) TRIAC dimming control system |
| CN102300355A (en) * | 2010-06-25 | 2011-12-28 | 英飞特电子（杭州）有限公司 | Light emitting diode (LED) dimming system |
| US20120314463A1 (en) * | 2011-06-09 | 2012-12-13 | Osram Sylvania Inc. | Power supply with restart circuit |
| CN203136247U (en) * | 2013-01-21 | 2013-08-14 | 苏州凯麒电子科技有限公司 | Valley fill circuit-based LED dimming power supply |
-
2015
- 2015-07-22 CN CN201510435970.9A patent/CN106358342B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101861016A (en) * | 2010-05-11 | 2010-10-13 | 南通中润照明电器有限公司 | Dimming switch power supply device of LED lamp |
| CN102300355A (en) * | 2010-06-25 | 2011-12-28 | 英飞特电子（杭州）有限公司 | Light emitting diode (LED) dimming system |
| CN202050568U (en) * | 2011-03-31 | 2011-11-23 | 南京汉德森科技股份有限公司 | Light-emitting diode (LED) TRIAC dimming control system |
| US20120314463A1 (en) * | 2011-06-09 | 2012-12-13 | Osram Sylvania Inc. | Power supply with restart circuit |
| CN203136247U (en) * | 2013-01-21 | 2013-08-14 | 苏州凯麒电子科技有限公司 | Valley fill circuit-based LED dimming power supply |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107461622A (en) * | 2017-09-14 | 2017-12-12 | 浙江生辉照明有限公司 | induction type bulb |
| CN107461622B (en) * | 2017-09-14 | 2023-12-12 | 浙江生辉照明有限公司 | Induction type bulb |
| CN108834253A (en) * | 2018-05-14 | 2018-11-16 | 卫斌鹏 | LED with overvoltage protection drives energy-saving power supply |
| CN108834253B (en) * | 2018-05-14 | 2020-07-24 | 佛山市蓝灯照明电器有限公司 | L ED driving energy-saving power supply with overvoltage protection |
| CN109819551A (en) * | 2019-02-22 | 2019-05-28 | 无锡安特源科技股份有限公司 | A kind of constant current light modulating device for LED light |
| CN113811041A (en) * | 2020-06-16 | 2021-12-17 | 矽诚科技股份有限公司 | Light-emitting diode module with sleep mode and light-emitting diode lamp string |
| CN113811041B (en) * | 2020-06-16 | 2024-03-05 | 矽诚科技股份有限公司 | LED module and LED light string with sleep mode |
| CN112803748A (en) * | 2021-01-29 | 2021-05-14 | 上海瞻芯电子科技有限公司 | Fixed feedforward control method for power factor correction circuit |
| CN114189958A (en) * | 2021-11-01 | 2022-03-15 | 广州市浩洋电子股份有限公司 | Device for reducing low-brightness jitter of light source by using vibration suppression module and lamp |
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