CN105430812B - A kind of LED drive circuit in supply line - Google Patents
A kind of LED drive circuit in supply line Download PDFInfo
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- CN105430812B CN105430812B CN201511007838.4A CN201511007838A CN105430812B CN 105430812 B CN105430812 B CN 105430812B CN 201511007838 A CN201511007838 A CN 201511007838A CN 105430812 B CN105430812 B CN 105430812B
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
- H05B45/30—Driver circuits
- H05B45/37—Converter circuits
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
- Y02B20/30—Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]
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Abstract
The present invention relates to the LED drive circuit in supply line, including：Inlet wire signal processing unit, power supply inlet wire signal is received, carry out two-way anti-interference filtration output city's electric signal；City's electric signal is converted into the DC signal containing ripple component and output；Single- stage PFC flyback switchs converting unit, receives the DC signal and city's electric signal, carries out pwm pulse modulation, obtains low-voltage dc signal and export；Automatic control signal condition and execution unit, the DC signal and city's electric signal are received, export the driving power signal changed in real time according to the electric characteristic of supply line；Output voltage current detecting unit, the low-voltage dc signal and driving power signal are received, converting unit output feedback ontrol signal is switched to single- stage PFC flyback.The circuit concentrates the output voltage values of voltage stabilizing power supply unit by adjusting in the reasonable scope, control information is carried in supply line, while still keep the voltage stabilizing function under the conditions of new voltage stabilizing value.
Description
Technical field
The present invention relates to LED drive circuit, more particularly to using lighting power supply line also serve as lamp control information LED drive electricity
Road.
Background technology
LED illumination technology achieves significant progress and development in recent years, with its very high luminous efficiency, impayable
Long-lived characteristic, excellent photochromic, driving convenience with flexibly and by the favorable comment of user.Although once had at the initial stage introduced to the market
Dispute after a while, but it is now perfect by constantly developing, received by users rapidly, and welcome popularization
The climax of popularization.
LED illumination technology application is wide, can not only apply in the family, can also be widely used in square, business
The public illumination occasion such as field, school, street lamp, airport, bridge, it is very high to have benefited from the luminous efficiency of its light fixture, can greatly reduce
The thermal losses of the energy, realize the green low-carbon environment-friendly in city illumination field, moreover it is possible to by introducing intelligent dimming control technology with setting
It is standby, real-time, flexible management control is carried out to light intensity according to being actually needed, further the economize on electricity potential of excavation LED illumination technology,
And city illumination is set to reach higher intelligent level.
Want to be controlled light intensity, mode usual at present there are two kinds：
One kind is to be preprogramed control mode, i.e., the relation curve of expected light intensity and time is made " illumination operation
Figure ", and in the embedded microprocessor in program downloads to LED driver, then after daily power-up, light fixture is all in microprocessor
Under the control of device, different lighting powers is selected according to residing different periods, i.e., automatically follows strictly predetermined illumination fortune
Row figure work, this mode is simple and convenient, but careful to lighting demand progress in advance conscientious must know the real situation, analyze with planning,
After programming determines, it is just fairly cumbersome to rethink modification.
Another kind is real-time commitment mode, not only above-mentioned " illumination service chart " can be passed through into signal on-line normalization side
Formula downloads in the embedded microprocessor in LED driver at any time as needed, can also be according to specific demand, at any time manually
Intervene the work of microprocessor, and then change the running status of light fixture immediately, that is, reach disengaging " illumination service chart " and flexibly enter
The purpose that row manipulates immediately.If along with the feedback information of light fixture running status is handled, modern intelligence could be really deserved to be called
The illumination monitoring management of change.
Above-mentioned second of controllable lighting management system have one it is apparent the characteristics of, that is, need a set of with the embedded place that declines
Manage device carry out real-time Communication for Power information transfer loop, this set information transfer loop can be it is wired, such as power line carrier,
RS485 industrial-controlled general lines etc. or wireless, such as the radio frequency transmission of point-to-multipoint, point-to-point RF relays, zigbee
Wireless networking etc..But these conventional transmission means all must separately lay the communications cable outside original lamp system at present
Or be equipped with wireless communication transmissions system equipment, and due to communication system equipment be independently of each between light fixture, and light fixture it is also required
It could be connected by such as 0-10V voltages control interface, 4-20mA current loops control interface or other digital control interfaces, it is real
Now to the real-time control of light fixture.
The content of the invention
Present invention aims to overcome that the deficiency of above prior art, proposes that one kind also serves as lamp control using lighting power supply line
The LED drive circuit of information, the technology path and method of another building communication lines are avoided completely, it is currently used various to overcome
Control method it is cumbersome and insufficient, succinctly conveniently realize and quick, control in real time realized to LED luminaire for public lighting, specifically
Realized by following technical scheme：
LED drive circuit in the supply line, including：
Inlet wire signal processing unit, power supply inlet wire signal is received, carry out two-way anti-interference filtration output city's electric signal；
City's electric signal is converted into the DC signal containing ripple component and output；
Single- stage PFC flyback switchs converting unit, receives the DC signal and city's electric signal, carries out pwm pulse modulation,
Again after high frequency transformer is depressured processing and secondary rectifying and wave-filtering, obtain low-voltage dc signal and export；
Automatic control signal condition and execution unit, the DC signal and city's electric signal are received, is exported according to supply line
The driving power signal that changes in real time of electric characteristic；
Output voltage current detecting unit, the low-voltage dc signal and driving power signal are received, by the reception
Signal is respectively correspondingly obtained by the resitstance voltage divider for being connected on sampling resistor in direct current output loop, DC output end is set
Current sampling data and voltage sample value, the backward single- stage PFC flyback switch conversion of amplified processing again of electric current, voltage sample value
Unit output feedback ontrol signal.
The further design of supply line's automatic control light adjusting type LED drive circuit is, in addition to isolated constant pressure limit
Closed loop feedback unit is flowed, the unit receives the amplified formation error signal of feedback control signal, then the error is believed
After number by linear optocoupler combining, single- stage PFC flyback switch converting unit is sent into, realizes closed loop feedback.
The further design of supply line's automatic control light adjusting type LED drive circuit is that the single- stage PFC flyback switchs
Converting unit includes rectification, filter function block, flyback dc-dc converter and APFC functional block,
The APFC function receives the DC signal of inlet wire signal processing unit output, and is cut
Ripple makes the electric current of inlet wire signal and the same same phase of frequency of primary voltage, exports the DC signal containing power frequency ripple component；
The flyback dc-dc converter is used to carry out pwm pulse modulation to the DC signal containing power frequency ripple component,
The DC signal containing power frequency ripple component is obtained, then is handled through high frequency transformer blocking and decompression, most afterwards through described
Rectification, filter function block secondary rectifying and wave-filtering after, obtain low-voltage direct output.
The further design of supply line's automatic control light adjusting type LED drive circuit is, the isolated constant voltage and current limiting
In closed loop feedback unit, feedback control signal amplifies to form error signal by three error amplifier TL431, respectively IC4,
IC5, IC6, wherein IC4 are voltage error amplifier, and IC6, IC5 collectively form current error amplifier, and IC4, IC5, IC6's is negative
Input is built-in with an accurate 2.5V source of stable pressure respectively, and output end is respectively arranged with one and expands stream triode, IC5, IC4 the moon
Pole is joined directly together, and is connected to optocoupler OPT1 internal illumination pipe negative pole, and IC5, IC4 anode and anode are also joined directly together, and are connected to institute
One end of direct current output sampling resistor is stated, IC6 negative electrode is connected to optocoupler OPT1 internal illumination pipe positive pole by divider resistance.
The further design of supply line's automatic control light adjusting type LED drive circuit is that the single- stage PFC flyback switchs
Converting unit include PWM switch control chips IC2, diode D2, D3, D5, switching tube Q1, electric capacity C5, C11 and resistance R1,
R2, R3, R4, R5, R6, R9, R11, R12, Q1 source electrode are grounded by resistance R11, and Q1 operating currents pass through the pressure formed during R1
Drop is used as current sampling signal, is sent to IC2 4 pin, and for realizing the overcurrent protection of power tube, Q1 grid is controlled by IC2, leads to
The parallel circuit for crossing resistance R9, D3 is connected to IC2 7 pin, and IC2 1 pin is to adjust voltage input end, the inlet wire signal transacting
The output end of unit connects IC2 3 pin after resistance R2, R3 and R4 sample partial pressure, and D5 positive pole is connected to by resistance R12
IC2 5 pin, IC2 8 pin are connected by R5, R6 with C5 positive pole, Q1 work the pulse current to be formed after transformation by diode
D2 carries out secondary rectification, then by C11 smothing filterings after, be sent to LED lamp through DC output end.
The further design of supply line's automatic control light adjusting type LED drive circuit is that the output voltage electric current is examined
Surveying unit includes resistance R21 and resistance R22, and R21, R22 are connected across the positive pole output of the feedback control signal output end of the unit
Between negative pole GND2, the dividing point of R22 upper ends is connected with IC4 reference electrode end, realizes voltage sample.
The further design of supply line's automatic control light adjusting type LED drive circuit is that the output voltage electric current is examined
Surveying in unit also includes R14, and R14 is connected between negative pole GND2 and the DC output end negative pole GND of reality, realizes that electric current is adopted
Sample.
The further design of supply line's automatic control light adjusting type LED drive circuit is that automatic control signal condition is with performing
Unit include microprocessor IC1, optocoupler OPT2, optocoupler OPT3, electric capacity C9, resistance R23, resistance R24, resistance R25, resistance R31,
Resistance R32, high frequency transformer, diode D6 rectifications, electric capacity C10 and the+5V exported provided with linear three terminal regulator IC3, IC3
Voltage is sent to IC1 20 pin, and electric capacity C9, resistance R23 connect and accessed between+5V accessory power supplys and ground, the tie point of series connection with
IC 1 pin is connected, and IC1 7 pin, 6 pin are respectively correspondingly connected to optocoupler OPT2 and optocoupler OPT3 interior light emitting diodes
Negative pole, the positive pole of two light emitting diodes are then connected to+5V power ends, optocoupler OPT2, OPT3 by resistance R29, R30 respectively
The colelctor electrode of internal phototriode is respectively correspondingly connected on the reference electrode of the IC4 by R31, R32, optocoupler OPT2
The emitter stage of internal phototriode is connected with the emitter stage of phototriode inside optocoupler OPT3, and is connected to IC4 anode,
R31, R32 are in parallel with R22 again after respectively correspondingly being connected with the phototriode in OPT2, OPT3.
The further design of supply line's automatic control light adjusting type LED drive circuit is, inlet wire signal processing unit bag
Inductance L1, electric capacity C1, electric capacity C2, electric capacity C3, electric capacity C4, fuse F1 and rectifier circuit are included, described C1, C2 are bridged respectively
In L1 both ends, C3, C4 concatenation is connected to the input of rectifier circuit again, and C3, C4 concatenation point are connected to protecting field
End, for filtering out the common mode disturbances on power input circuit, the F1 is connected between power supply L lines input and C1 positive pole and used
In overcurrent protection.Advantages of the present invention is as follows：
The present invention carries out deep technological transformation to common single- stage PFC inverse-excitation type switch power-supply, on the one hand introduces micro- place
Device is managed, continuously sampling analysis is carried out to the electric parameter of incoming power, identifies what electric parameter change was implied at any time
Control information, on the other hand introduce adjustable interface, as needed, microprocessor in the closed loop feedback control loop of constant current constant voltage
Sample circuit can be exported to driver by the interface and carry out rapid structural parameter adjustment, on the premise of a reference source is constant,
Be achieved constant pressure, current limliting adjusts the change on demand of numerical value, so as to reach the purpose for changing adjustment lamp power.
LED driver of the present invention with concentrate voltage stabilizing power supply unit be used cooperatively, remote illumination control centre according to
The real-time control information needed, the output voltage values of voltage stabilizing power supply unit are concentrated by adjusting in the reasonable scope, control is believed
Breath is carried in supply line, while still keeps the voltage stabilizing function under the conditions of new voltage stabilizing value.
Brief description of the drawings
Fig. 1 is the structured flowchart for supply line's automatic control light adjusting type LED driver that patent of the present invention proposes.
Fig. 2 is the one embodiment for supply line's automatic control light adjusting type LED driver that patent of the present invention proposes.
Fig. 3 is TL431 symbol and internal equivalent schematic diagram.
Embodiment
The present invention program is described in detail below.
Such as Fig. 1, the LED drive circuit includes：A inlet wires signal processing unit, B single- stage PFCs flyback switch converting unit, C
The isolated constant voltage and current limiting closed loop feedback unit of output voltage current detecting unit, D and E automatic controls signal condition and execution unit.
The function of wherein various pieces is as follows：
A inlet wire signal processing units
The part is connected between the power supply inlet wire of LED driver and single- stage PFC flyback switch converting unit, inlet wire filter
Ripple link carries out two-way anti-interference filtration, has both isolated influence of the power network clutter to driver, and driver for isolating internal electron member
Pollution of the harmonic wave to power network caused by part work.Civil power after filtered is converted to containing the straight of ripple component in rectification link
Stream electricity, there is provided converting unit is switched to single- stage PFC flyback, to realize that the PFC to civil power input is prepared.Surge
Link of protection filters some surge protection elements being equipped with link by inlet wire and formed, too high in power supply for absorbing
Transient electrical pulses or released into ground.
B single- stage PFC flyback dc-dc converters
PFC flyback dc-dc converters are connected between " inlet wire signal processing unit " and " output voltage current detecting unit ",
Realize the isolation between DC-DC conversions and primary and secondary.
PFC flyback dc-dc converters are the core components of LED driver.Single- stage PFC flyback dc-dc converter is by two-stage
PFC flybacks dc-dc converter, which simplifies, to be formed.Traditional pfc circuit is typically scheduled at before flyback switching converter circuit, the two
Series relationship is formed, wherein PFC is " APFC ", and the technology is provided rectification link according to specific rule
DC voltage carries out copped wave, exports the DC signal containing power frequency ripple component, and inlet wire current can be forced to reach and inlet wire electricity
Pressure is with the same phase of frequency, and waveform keeps consistent with inlet wire sinusoidal voltage waveform, to realize that power factor is approximately 1 perfect condition；
Another aspect flyback dc-dc converter is used to carry out pwm pulse modulation to the direct current after the processing of PFC levels, obtains containing power frequency arteries and veins
The DC signal of dynamic composition, then after high frequency transformer is depressured processing and secondary rectifying and wave-filtering, obtain required low-voltage direct
Output, is a DC-DC translation process.
Every grade of two-stage PFC flybacks dc-dc converter is required for a power switch pipe, and use here " single- stage PFC is anti-
Energizing switch converter ", then it is that the function of the two combines together, coordinates peripheral component using a power switch pipe, you can
The function of needing two power switch pipes to realize originally is completed simultaneously.After the particular architectures of circuit also eliminate rectification link
For a high-voltage electrolytic capacitor of smothing filtering, therefore, single- stage PFC flyback dc-dc converter is simple in construction, and power consumption is relatively low, makes
Equipment dependability improves, and the life-span is longer.But the requirement to power switch pipe and the secondary rectifying and wave-filtering of low-pressure side is higher.
C output voltage current detecting units
It is approximately linear relationship between LED operating current and luminous intensity, and LED is to operating voltage
Stability is very sensitive, and its reason is that its V-I characteristic curves are very big, and the change of small supply voltage can cause electricity
Stream larger change, in addition, LED be not conventional, electric-resistance load, its characteristic curve can also with temperature change occur compared with it is big
Horizontal displacement, even if supply voltage is highly stable, electric current equi-stable is cannot guarantee that, therefore, LED drive power does not merely have to
There is the basic stabilizing voltage characteristic of D.C. regulated power supply first, the ability must also simultaneously with detection and steady operation electric current.It is defeated
It is exactly to be set for this purpose to go out voltage and current detecting unit.The detection of output voltage passes through the electricity that is set in DC output end
Resistance divider obtains voltage sample value, and the detection of output current is then sampling resistor of being connected in direct current output loop, resistance terminal
Voltage is current sampling data.After two amplified processing of sampled value, as feedback control signal to PFC flyback dc-dc converters
Output be controlled, reach voltage stabilization and current stabilization purpose, while also achieve the protection to equipment and light fixture.
When load current is less than current stabilization threshold value, driver is run with voltage regulation way；And when load current reaches current stabilization threshold
When being worth or having more than current stabilization threshold value tendency, driver seamlessly transits to be run for current stabilization mode.It should be noted that basic voltage stabilizing
Threshold value can not only be set with current stabilization threshold value by adjusting respective potentiometer of adjusting, can also be under micro-processor control
Set by changing the intrinsic standoff ratio of above-mentioned resitstance voltage divider or the magnifying power of current sample treatment loop.
The isolated constant voltage and current limiting closed loop feedback units of D
Isolated constant voltage and current limiting closed loop feedback unit is connected to " output voltage current detecting and protection " loop and " single- stage PFC
Between the PWM/PFC control chips of flyback dc-dc converter ", the isolation for control signal is transmitted.
In order that the safety used is with conveniently, reducing harmful effect of the interference signal to complete machine stability, LED driver
What ac power supply circuit must be entirely isolated with direct current output loop.It is anti-in order to form the closed loop between output and input circuit
Feedback, it is necessary to which the isolation for realizing control signal by a kind of device of photo-coupler is transmitted.Here linear optocoupler is used, in the future
It is combined from the voltage of error amplifier with current feedback signal in optocoupler primary, and the signal that secondary is obtained is sent into flyback
The pwm chip of dc-dc converter, the parameter of pulse is exported with the direct current output of robust driver for changing it.
E automatic controls signal condition and execution unit
The unit is different from general LED driver, and the power for providing LED lamp driving is to change in real time
, and this change need not add any communication line or communication apparatus, as long as being connected to supporting adjustable AC voltage-stabilizing
It can be achieved in the supply line that power supply is sent.
Automatic control signal condition and execution unit are connected between power supply input circuit and measure voltage ＆ current loop, for basis
The electric characteristic of supply line controls the constant pressure and flow threshold value that driver exports, and then completes to run power to LED lamp
Management and control.The core of automatic control signal condition and execution unit is embedded microprocessor, and its forward path of the devices use is to power supply
The electric parameter of input circuit is sampled, and after being handled by analysis with calculating, obtains being supplied to the driving power of LED lamp
Code, executing agency is then driven by backward channel, structure conversion is carried out to constant voltage and current limiting closed feedback loop, and then change
Voltage sampling and current sampling value, complete adjusting and regulate and control to the driving power of LED lamp.
With reference to the embodiment in Fig. 2, the technology performance of patent of the present invention is described in detail.
Wherein A inlet wires signal processing unit and B single- stage PFC flyback dc-dc converters is as follows：
Power supply enters line and introduced from J1, and piezo-resistance RV1 is used to absorb the voltage surge being likely to occur, fuse F1
For overcurrent protection.Inductance L1, electric capacity C3, C4 are used to filter out the common mode disturbances on power input circuit, and electric capacity C1 and C2 is then used
In filtering out DM EMI.Then, 1, the 3 ends progress all-wave that the AC power after filtering process is sent to bridge rectifier B1 is whole
Stream, turns into the direct current negative pole ground connection with ripple component, and positive pole is added to main VMOS by high frequency transformer T1 primary coil
In switching tube Q1 drain electrode.Main VMOS switching tubes Q1 source electrode is grounded by resistance R11, and Q1 operating currents pass through what is formed during R1
Pressure drop is sent to PWM switch control chips IC2 (SA7527) the 4th pin, for realizing the mistake of power tube as current sampling signal
Stream protection；Switching tube Q1 grid is controlled by IC2, i.e., the control that chip IC 2 is connected to by resistance R9, D3 parallel circuit is defeated
Go out end (7 pin).IC2 the 1st pin for adjustment voltage input end, change the pin voltage can control chip working condition.By
Need to realize that PFC corrects according to the DC pulse moving voltage waveform after inlet wire rectification in IC2, so the output (C5 by rectifier
Upper end) after resistance R2, R3 and R4 sample partial pressure, drawn from dividing point (R4 upper ends) and be sent to the pin of IC2 the 3rd.IC2 switch drives
The dynamic return-to-zero for also needing to detect magnetic flux in high frequency transformer, therefore, by high frequency transformer T1 secondary coil (with diode D5
The tie point of positive pole) pin of IC2 the 5th are connected to by resistance R12.IC2 power itself is grounded for the 6th pin (negative pole), and positive pole
8th pin has two articles of current supply circuits, and one is derived from rectifier bridge output point i.e. C5 upper ends+250V places, is sent after resistance R5 and R6 decompression
8th pin, applied when starting for power-up, another auxiliary power output end for being derived from high frequency transformer, i.e. coil N3 is through diode
At the DC power anode VF provided after D5 rectifications, resistance R15 and electric capacity C12 filtering, the pin of IC2 the 8th are equally sent, as circuit just
IC2 long-term work power supply after Chang Qizhen.Switching tube Q1 work the pulse current to be formed through transformer be converted to needed for voltage etc.
After level, exported through secondary coil N2, secondary rectification is carried out by diode D2, after C11 smothing filterings, is sent to through DC output end
LED lamp.
C output voltages current detection circuit is used to sample voltage, the electric current of direct current output, as monitoring adjustment
Foundation.Sampling wherein to voltage is realized by divider resistance R21 and R22, and they are connected across positive pole output and negative pole
Between GND2, dividing point (R22 upper ends) is connected to " three end adjustable shunt reference voltage sources " IC4 (TL431) reference electrode end,
Realize voltage sample；Sampling to electric current is completed by the current sampling resistor R14 being connected in negative pole output loop,
R14 left end connection GND2, right-hand member tie point is GND, and GND is actual DC output end negative pole, therefore, flows through the electricity of load
Stream must be all by R14, so as to realize current sample.
The isolated constant voltage and current limiting closed loop feedbacks of D and protective loop, for being obtained according to the sampled value in measure voltage ＆ current loop
Error signal after to amplification, and this signal is transmitted to PWM switch control chips by photoelectric coupler isolation, realize closed loop
Feed back to reach the constant pressure to direct current output, Current limited Control purpose.Voltage and current error amplifier in the present embodiment by
" three end adjustable shunt reference voltage sources " TL431 is formed, and wherein IC4 serves as voltage error amplifier, and IC6, IC5 are collectively formed
Current error amplifier.
TL431 symbol and internal equivalent schematic diagram are as shown in Figure 3.As seen from the figure, TL431 can be equivalent to a high-gain
Operational amplifier, and accurate 2.5V source of stable pressure built in the negative input end in amplifier, set in the output end of amplifier
One is expanded stream triode, and the positive input terminal of amplifier is equivalent to the reference electrode of device, the colelctor electrode of above-mentioned expansion stream triode
Equivalent to the negative electrode of device, and expand anode of the emitter stage equivalent to device of stream triode.When device is returned as closed loop feedback
During a link in road, if the dividing point of foregoing output voltage measure loop is connected to TL431 reference electrode, that is, connect
When being connected to the positive input terminal of high gain operational amplifier, because the negative input end of high gain operational amplifier is by internal precision voltage stabilizing
The stable clamper in source adjusts theoretical in 2.5V voltages according to closed loop, and the virtual voltage that dividing point obtains will necessarily be made to be equal to 2.5V,
Then determined by the total voltage of partial pressure by the resistance of two divider resistances, that is to say, that output voltage is defined in：U0/
2.5V=(R21+R22)/R22.
The regulation process of voltage stabilizing loop
In the present embodiment, linear optical coupling OPT1 current transfer ratios are 1:1, both isolated the electricity on primary and secondary both sides herein
Gas connects, and and can effectively realizes the transmission of useful electric signal between primary and secondary.Linear optical coupling OPT1 internal illumination pipes positive pole connects
Direct current output positive terminal, the negative pole of luminous tube are connected to IC4 negative electrode, and IC4 anode meets GND2, forms the primary of isolation control
Side.Direct current output positive pole terminal voltage is caused to occur increasing trend when drift occurs for external condition change or line component characteristic
When, the voltage of R21 and R22 dividing points will deviate from 2.5V and increase therewith, because dividing point is connected on the input of the same name of amplifier, amplifier
Output also tend to raise, built in amplifier output end triode internal resistance reduce so that flow through the electricity of optocoupler OPT1 light emitting diodes
Stream increase, after light-coupled isolation is transmitted, will tend to increase as terminal voltage on the resistance R16 of optocoupler secondary load, change warp
R7 is transmitted to the pin of chip IC 2 the 1st, and after chip internal is handled, the driving pulse dutycycle of the 7th pin output reduces, and causes Q1 electric
Service time reduction is flowed, causes high frequency transformer secondary D2 direct current output to tend to decline.The knot of so a series of closed loop regulation and control
Fruit, VD will be made to keep stable., whereas if external condition changes or line component characteristic occurs drift and caused
When reduction trend occurs in direct current output positive pole terminal voltage, the change of opposite direction will be presented in above-mentioned regulation process, equally makes direct current
Output voltage keeps stable.
The regulation process of current stabilization loop
In the present embodiment, the regulation process of current stabilization loop is more slightly more complex than the regulation process of voltage stabilizing loop.Current stabilization ring
The controlling element IC5 on road is also " three end adjustable shunt reference voltage sources " TL431, the controlling element IC4 with voltage stabilizing loop
It is identical.Element IC5, IC4 negative electrode are joined directly together, and are connected to optocoupler OPT1 internal illumination pipe negative pole, IC5, IC4 anode and sun
Pole is also joined directly together, and is connected to direct current output sample resistance R14 left end (GND2), can according to their this quite similar connections
To find out, their closed loop control process is also quite similar.It is another have a TL431 (IC6) be used for produce 2.5V
Reference voltage, and after potentiometer W1 and resistance R19 partial pressures, generate one and be slightly less than 2.5V's for GND ground terminals
Voltage, and this voltage is sent on the controlling element IC5 reference edge of current stabilization loop.Pay attention to, because sample resistance R14 is concatenation
In output negative terminal, the direction that load current flows through sample resistance R14 is from right to left, coil N2 lower ends to be back to, if with GND
End is used as real 0V reference points, and R14 left end (GND2) place is then the little negative voltage of a numerical value.(as an example it is assumed that
R14 is 0.1 ohm, load current 2A, then the negative voltage at R14 left end GND2 is：- 2A × 0.1=-0.2V).If adjustment
W1 makes the voltage of W1 and R19 dividing points reach 2.3V relative to GND, i.e., when IC5 reference voltage terminal is 2.3V, due to IC5's
Anode is connected at GND2, and its reference edge has just reached 2.5V relative to the voltage of anode, that is, has reached current stabilization or limit
Stream starts to control a little.If now external condition, load etc. is changed or line component characteristic is drifted about, cause output electricity
When stream tends to increase, the absolute value of GND2 ends negative pressure tends to increase, and makes IC5 reference edges also tend to increase relative to the voltage of anode
Greatly, this, which is resulted in, generates regulation process very similar when being raised with voltage stabilizing loop voltage, output current is kept stable.
If situation is on the contrary, load etc. changes or the generation drift of line component characteristic is to cause output current to tend to
Reduce, then there are two kinds of possibility, a kind of is although IC5 reference edges tend to reduce relative to the voltage of anode, but still above 2.5V bases
Quasi- value, at this moment output current continues to keep stable cut-off current under loop control；Another kind is IC5 reference edges relative to anode
Voltage be decreased to below 2.5V a reference values, now IC5 essentially drops out control loop, circuit degradation to the list for being only controlled by IC4
Pure voltage stabilizing state.
As can be seen from the above analysis, although IC4, IC5 reference voltage 2.5V are unalterable, as long as closing
Change the intrinsic standoff ratio of R21, R22 in voltage sampling loop in the range of reason, it is possible to the convenient voltage stabilizing for changing VD
Value；Equally, the intrinsic standoff ratio of W1, R19 in electric current comparison loop are changed in the reasonable scope, it is possible to easily change direct current output
The cut-off current of electric current.In the present invention, circuit structure should exactly be innovated in this way, makes LED driver can be with
Adjust the luminous power of light fixture on demand under the management and control of microprocessor.
E automatic controls signal condition and execution unit
The power that the unit provides LED lamp driving can change in real time, and this change need not
Additional any communication line or communication apparatus, as long as being connected in the supply line that supporting adjustable alternating current steady voltage plug is sent i.e.
It can be achieved.
Such as Fig. 2, J3 introduces the ac voltage signal after anti-interference filtration in loop, is concatenated resistance R24, R25 current limliting
Afterwards, after by full-bridge rectifier B2 rectifications, electric capacity C21 smothing filterings, the sampled signal directly proportional to input supply voltage is obtained, is passed through
After the appropriate partial pressure of resistance R27, R28, the microprocessor IC1 pin of A/D converter input 14 is sent to, at microprocessor
Reason.
Due to also having full-bridge rectifier in major loop, it is appropriate to be passed through from the DC output end of major loop full-bridge rectifier
Voltage division processing after obtain primary voltage sampled signal, but must take into consideration reinforcement isolation, reduce the influence to major loop as far as possible,
Prevent from causing the change of the condition of work and working condition of major loop.
The working power of microprocessor is derived from the N3 coils of foregoing high frequency transformer, is put down through diode D6 rectifications, electric capacity C10
After sliding filtering, 15V or so DC auxiliary supply is obtained, ensures that microprocessor power supply is stable to reduce ripple interference, provided with line
Property three terminal regulator IC3 (78L05), C17, C18 be respectively input, output end filter capacitor, IC3 output+5V voltages be sent to
The pin of power supply of microprocessor pin 20.Electric capacity C9, resistance R23 connect and accessed between+5V accessory power supplys and GND1, and it is connected in series
Point send the pin of microprocessor reset pin 1.The 7th pin, the 6th pin of microprocessor are connected respectively to the interior of optocoupler OPT2 and optocoupler OPT3
The negative pole of portion's light emitting diode, and the positive pole of two light emitting diodes is then connected to+5V power supplys by resistance R29, R30 respectively
End.The colelctor electrode of phototriode is concatenated resistance R31 and is connected to foregoing three ends adjustable shunt reference voltage inside optocoupler OPT2
On source IC4 reference electrode, the colelctor electrode of phototriode is concatenated the ginseng that resistance R32 is also connected to IC4 inside optocoupler OPT3
Examine on electrode；The direct phase of emitter stage of the emitter stage of phototriode and phototriode inside optocoupler OPT3 inside optocoupler OPT2
Even, IC4 anode (GND2) is connected to jointly.As seen from Figure 2, it is after resistance R31 connects with the phototriode in OPT2
Directly it is parallel on resistance R22, is parallel to after resistance R32 connects with the phototriode in OPT3 and directly resistance R22
On, controlled using the switch to two optocouplers, R31, R32 can be made in parallel with resistance R22 with 4 kinds of different combinations,
Also the intrinsic standoff ratio of output voltage sampling is just changed indirectly, and then realizes the adjustment control to output voltage.
Specifically, when it is low level that microprocessor I/O output pins, which only have the 7th pin, OPT2 luminous tube electrified light emitting,
Internal phototriode conducting, R31 quilts are simultaneously connected on R22, are reduced R22 resistances, intrinsic standoff ratio increase, are exported on DC voltage
Rise；Similarly, when it is low level that microprocessor I/O output pins, which only have the 6th pin, R32 quilts are simultaneously connected on R22, subtract R22 resistances
It is small, the resistance of reasonable selection R31, R32, make both resistances inconsistent, partial pressure can be made to obtain 4 grades of applicable numerical value, that is, obtained
Four kinds of different LED power.
Other pins of microprocessor, wherein the 10th pin is with being connected to power supply (GND1), the 2nd pin RXD, the 3rd pin TXD are used for pair
Microprocessor downloads application program, and crystal oscillator JT1 is connected between the 4th, the 5th pin, work clock is provided for microprocessor.
The primary voltage sampled signal of the microprocessor IC1 pin of A/D converter input 14 is sent to, is entered in the microprocessor
Row analog-to-digital conversion, then converting result data is analyzed by processor.Because primary voltage is steady by the concentration of auxiliary work
Depressor provides, and not only operating voltage can adjust as requested, and can ensure that operating voltage keeps permanent in setting range
It is fixed constant.Every LED driver is according to the analysis to A/D transformation results, you can the intention at Lighting control center is calculated, and then
Control of the backward output channel realization to lamp power is passed through using preceding method.
Claims (7)
- A kind of 1. LED drive circuit in supply line, it is characterised in that including：Inlet wire signal processing unit, power supply inlet wire signal is received, carry out two-way anti-interference filtration output city's electric signal；By institute State city's electric signal and be converted to the DC signal containing ripple component and output；Single- stage PFC flyback switchs converting unit, receives the DC signal and city's electric signal, carries out pwm pulse modulation, then pass through After high frequency transformer decompression processing and secondary rectifying and wave-filtering, obtain low-voltage dc signal and export；Automatic control signal condition is with performing Unit, the DC signal and city's electric signal are received, the driving work(changed in real time according to the generation of the electric characteristic of supply line Rate signal simultaneously exports the signal；Output voltage current detecting unit, receive the low-voltage dc signal and driving power signal, by low-voltage dc signal with Driving power signal is respectively correspondingly divided by the resistance for being connected on sampling resistor in direct current output loop, DC output end is set Depressor obtains current sampling data and voltage sample value, and electric current, voltage sample value are amplified again to handle the backward single- stage PFC flyback Switch converting unit output feedback ontrol signal；Isolated constant voltage and current limiting closed loop feedback unit, the isolated constant voltage and current limiting closed loop feedback unit receive the feedback control The amplified formation error signal of signal, then by the error signal by linear optocoupler combining after, be sent into single- stage PFC it is anti- Energizing switch converting unit, realizes closed loop feedback；In the isolated constant voltage and current limiting closed loop feedback unit, feedback control signal is amplified by three error amplifier TL431 Error signal, respectively IC4, IC5, IC6 are formed, wherein IC4 is voltage error amplifier, and IC6, IC5 collectively form electric current mistake Poor amplifier, IC4, IC5, IC6 negative input end are built-in with an accurate 2.5V source of stable pressure respectively, and output end is respectively arranged with one Individual to expand stream triode, IC5, IC4 negative electrode are joined directly together, and are connected to optocoupler OPT1 internal illumination pipe negative pole, IC5, IC4 anode Also it is joined directly together with anode, is connected to one end of the sampling resistor, IC6 negative electrode is connected in optocoupler OPT1 by divider resistance Portion's luminous tube positive pole.
- 2. the LED drive circuit in supply line according to claim 1, it is characterised in that the single- stage PFC flyback is opened Closing converting unit includes rectification, filter function block, flyback dc-dc converter and APFC functional block,The APFC functional block receives the DC signal of inlet wire signal processing unit output, and carries out copped wave Make the electric current and the same same phase of frequency of primary voltage of inlet wire signal, export the DC signal containing power frequency ripple component；The flyback dc-dc converter is used to carry out pwm pulse modulation to the DC signal containing power frequency ripple component, obtains The DC signal containing power frequency ripple component, then handled through high frequency transformer blocking and decompression, most afterwards through the rectification, After the secondary rectifying and wave-filtering of filter function block, the low-voltage direct output is obtained.
- 3. the LED drive circuit in supply line according to claim 2, it is characterised in that the single- stage PFC flyback is opened Closing converting unit includes PWM switch control chips IC2, diode D2, D3, D5, switching tube Q1, electric capacity C5, C11 and resistance R1, R2, R3, R4, R5, R6, R9, R11, R12, Q1 source electrode are grounded by resistance R11, and Q1 operating currents pass through what is formed during R1 Pressure drop is sent to IC2 4 pin as current sampling signal, and for realizing the overcurrent protection of power tube, Q1 grid is controlled by IC2, IC2 7 pin are connected to by resistance R9, D3 parallel circuit, IC2 1 pin is to adjust voltage input end, at the inlet wire signal The output end for managing unit connects IC2 3 pin after resistance R2, R3 and R4 sample partial pressure, and D5 positive pole is connected to by resistance R12 IC2 5 pin, IC2 8 pin are connected by R5, R6 with C5 positive pole, Q1 work the pulse current to be formed after transformation by diode D2 carries out secondary rectification, then by C11 smothing filterings after, be sent to LED lamp through DC output end.
- 4. the LED drive circuit in supply line according to claim 3, it is characterised in that the output voltage electric current inspection Surveying unit includes resistance R21 and resistance R22, and the feedback control signal that R21, R22 are connected across output voltage current detecting unit is defeated Go out between the positive pole output at end and negative pole GND2, the dividing point of R22 upper ends is connected with IC4 reference electrode end, realizes that voltage is adopted Sample.
- 5. the LED drive circuit in supply line according to claim 4, it is characterised in that the output voltage electric current inspection Surveying in unit also includes R14, and R14 is connected between negative pole GND2 and the DC output end negative pole GND of reality, realizes that electric current is adopted Sample.
- 6. the LED drive circuit in supply line according to claim 4, it is characterised in that automatic control signal condition is with performing Unit include microprocessor IC1, optocoupler OPT2, optocoupler OPT3, electric capacity C9, resistance R23, resistance R24, resistance R25, resistance R31, Resistance R32, high frequency transformer, diode D6 rectifications, electric capacity C10 and the+5V exported provided with linear three terminal regulator IC3, IC3 Voltage is sent to IC1 20 pin, and electric capacity C9, resistance R23 connect and accessed between+5V accessory power supplys and ground, the tie point of series connection with IC 1 pin is connected, and IC1 7 pin, 6 pin are respectively correspondingly connected to optocoupler OPT2 and optocoupler OPT3 interior light emitting diodes Negative pole, the positive pole of two light emitting diodes are then connected to+5V power ends, optocoupler OPT2, OPT3 by resistance R29, R30 respectively The colelctor electrode of internal phototriode is respectively correspondingly connected on the reference electrode of the IC4 by R31, R32, optocoupler OPT2 The emitter stage of internal phototriode is connected with the emitter stage of phototriode inside optocoupler OPT3, and is connected to IC4 anode, R31, R32 are in parallel with R22 again after respectively correspondingly being connected with the phototriode in OPT2, OPT3.
- 7. the LED drive circuit in supply line according to claim 1, it is characterised in that inlet wire signal processing unit bag Inductance L1, electric capacity C1, electric capacity C2, electric capacity C3, electric capacity C4, fuse F1 and rectifier circuit are included, described C1, C2 are bridged respectively In L1 both ends, C3, C4 concatenation is connected to the input of rectifier circuit again, and concatenation point connects protection ground terminal, for filtering out Common mode disturbances on power input circuit, the F1 is connected between inlet wire L ends and C1 positive pole, for overcurrent protection.
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| CN201511007838.4A CN105430812B (en) | 2015-12-28 | 2015-12-28 | A kind of LED drive circuit in supply line |
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Families Citing this family (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9942971B2 (en) * | 2016-08-15 | 2018-04-10 | Ford Global Technologies, Llc | Detecting outages in a LED lamp assembly |
| CN106793410B (en) * | 2017-01-03 | 2023-10-10 | 广州视声智能股份有限公司 | Dimmer circuit |
| EP3484011B1 (en) | 2017-04-25 | 2021-09-01 | Guangdong Oppo Mobile Telecommunications Corp., Ltd. | Power supply device and charging control method |
| CN107135593B (en) * | 2017-06-07 | 2023-12-05 | 深圳市奥金瑞科技有限公司 | Intelligent switch detection and identification circuit |
| CN107579732B (en) * | 2017-09-20 | 2023-09-26 | 广东机电职业技术学院 | Analog switch circuit based on radio frequency switch chip |
| CN109804541B (en) * | 2017-09-22 | 2021-05-18 | Oppo广东移动通信有限公司 | Power supply circuit, power supply device, and control method |
| EP3657660B1 (en) * | 2017-09-22 | 2021-07-07 | Guangdong Oppo Mobile Telecommunications Corp., Ltd. | Power supply circuit, power supply device, and control method |
| CN108633139B (en) * | 2018-05-16 | 2020-07-07 | 东莞市紫能电子科技有限公司 | Power supply device with two paths of stable outputs and control method thereof |
| US11617531B2 (en) * | 2018-11-23 | 2023-04-04 | Mediatek Inc. | Circuit applied to biopotential acquisition system |
| CN112087842B (en) * | 2019-05-27 | 2024-04-26 | 李宗凤 | Practical LED driver |
| CN111014903B (en) * | 2020-01-06 | 2024-06-04 | 深圳市佳士科技股份有限公司 | Anti-interference switch signal processing circuit and welding and cutting equipment |
| CN111277247A (en) * | 2020-03-26 | 2020-06-12 | 苏州灵猴机器人有限公司 | Position pulse input circuit and driving method thereof |
| US11924934B2 (en) * | 2021-06-28 | 2024-03-05 | ERP Power, LLC | Dynamic filtering of dimmable LED drivers |
| CN114826329A (en) * | 2022-03-31 | 2022-07-29 | 昂宝电子（上海）有限公司 | Signal transmission device and method |
| CN118075953B (en) * | 2024-04-19 | 2024-08-06 | 厦门普为光电科技有限公司 | Dimming circuit with load capacity adjusting mechanism and method thereof |
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| KR101072057B1 (en) * | 2009-08-18 | 2011-10-11 | 엘지이노텍 주식회사 | LED Driving Circuit |
| CN102215617A (en) * | 2010-04-09 | 2011-10-12 | 复旦大学 | Partition type driving circuit for general lighting LED (light emitting diode) street lamp |
| EP2656691B1 (en) * | 2010-12-21 | 2023-06-28 | Signify Holding B.V. | Method and apparatus to limit current overshoot and undershoot in light driver |
| CN102523663B (en) * | 2012-01-06 | 2014-05-07 | 广州市隆都电子有限公司 | Constant-power LED drive circuit |
| CN104022661B (en) * | 2014-06-11 | 2017-02-15 | 合肥工业大学 | Switching power supply for AC/DC-DC self-adaptive instrument within ultra-wide voltage input range |
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