CN202857100U - Linear constant current current sharing LED driving circuit and circuit board structure thereof - Google Patents

Linear constant current current sharing LED driving circuit and circuit board structure thereof Download PDF

Info

Publication number
CN202857100U
CN202857100U CN 201220565732 CN201220565732U CN202857100U CN 202857100 U CN202857100 U CN 202857100U CN 201220565732 CN201220565732 CN 201220565732 CN 201220565732 U CN201220565732 U CN 201220565732U CN 202857100 U CN202857100 U CN 202857100U
Authority
CN
China
Prior art keywords
led
current
constant current
unit
sharing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn - After Issue
Application number
CN 201220565732
Other languages
Chinese (zh)
Inventor
李佳颖
褚辰
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hasco Vision Technology Co Ltd
Original Assignee
Shanghai Koito Automotive Lamp Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shanghai Koito Automotive Lamp Co Ltd filed Critical Shanghai Koito Automotive Lamp Co Ltd
Priority to CN 201220565732 priority Critical patent/CN202857100U/en
Application granted granted Critical
Publication of CN202857100U publication Critical patent/CN202857100U/en
Anticipated expiration legal-status Critical
Withdrawn - After Issue legal-status Critical Current

Links

Images

Landscapes

  • Circuit Arrangement For Electric Light Sources In General (AREA)

Abstract

The utility model discloses a linear constant current current sharing LED driving circuit and a circuit board structure thereof relating to the arrangement of the driving circuit and the elements of the driving circuit of the vehicle LED illuminating device. The linear constant current current sharing LED driving circuit comprises a reference voltage unit, a constant current feedback unit, and a multipath sampling current sharing unit. The multipath sampling current sharing unit is correspondingly connected with all LED strings of a multipath LED illuminating module. All current sampling feedback ends are parallely connected with a feedback signal input end of the constant current feedback unit. An LED shifting resistor disposed on the LED circuit board can be used to adjust the LED current automatically, and the constant current feedback unit can be used to control the currents of the LED strings. In the utility model, the constant current, the current sharing, the LED shifting, and the PWM light modulation functions can be provided, various practical requirements of the automobile electronic illumination can be satisfied, the complexity of the design and the production of the LED driving circuit can be greatly reduced, and the error probability can be reduced. No parameter changes of elements of the control circuit board are required during the production or the maintenance process, the high exchangeability of the circuit board product can be realized, and the production efficiency can be improved.

Description

A kind of linear constant current current-sharing led drive circuit and circuit board structure thereof
Technical field
The utility model relates to the layout for general vehicle illumination or signalling, relates in particular to the layout for drive circuit and the element thereof of LED lighting device.
Background technology
LED has fast response time, low-power consumption, energy-conservation, the remarkable advantage such as the life-span is long.Owing to the rapid response speed of LED, be specially adapted to the application of automobile brake lamp and direction indicator lamp, can reduce the probability of happening of the traffic accidents such as rear-end collision.Along with the raising of semi-conducting material and packaging technology, luminous flux and the light extraction efficiency of led light source improve gradually, and led light source has been widely used in the special lighting fields such as traffic lights, automotive lighting, billboard.The LED Driving technique is also progressively developed along with the development of LED application technology.
LED is a kind of along with the variation by the LED current value changes the well-illuminated light emitting source of light, if therefore need LED luminous constant, it is constant then must to control the current value that flows through LED.Usually the LED that adopts drives the constant current method linear adjustable type and two kinds of methods of switch regulating type.The core technology of linear regulation formula is to utilize the switching tube that works in the range of linearity to come control load as a dynamic adjustable resistance, to guarantee in the situation that input voltage changes, the power consumption that the switching tube load is different, thus the electric current that flows through the LED load is remained unchanged substantially.But this Driving technique is subjected to the restriction of input voltage range, and load LED number is restricted, and for Vehicular lamp, limited by vehicle power supply voltage, and the LED that is connected in series is generally below 3.Need usually to need multi-channel linear adjustable type circuit to drive the LED multi-path string when driven when having greater than 3 LED, to guarantee that a number in every paths of LEDs string is less than or equal to 3.Chinese invention patent application " a kind of multichannel constant-current control circuit that is applicable to led driver " (application for a patent for invention number: 200910153405.8 publication numbers: CN101674693A) disclose a kind of multichannel constant-current control circuit that is applicable to led driver, comprise single output constant current source and multiplex output circuit, it is characterized in that described each output circuit comprises a constant current branch road, an equalizing control circuit and the load that is formed by a plurality of LED lamps, the input of described every way equalizing control circuit is from the sampled signal of this road sample resistance to output current, through becoming public connecting line after this road constant current branch road conversion, link together with other each road, become the current-sharing bus, every road current sampling signal and current-sharing bus voltage are after equalizing control circuit inside compares adjusting, the output signal of equalizing control circuit can be controlled the linear impedance magnitude of adjusting pipe of corresponding constant current branch road, then control the size of every road electric current, realize current-sharing.Although the technical scheme of this invention has solved the problem of multiple constant current control, but each road output circuit of this technical scheme comprises a constant current branch road and an equalizing control circuit, and circuit structure is complicated, not only improved cost, the increase of circuit elements device also can reduce reliability.
(Chinese invention patent application number: 02815162.3 publication number: CN 1537403A) disclose a kind of integrated LED drive unit for a plurality of LED strings that the PCT application for a patent for invention that enters China " is used for the integrated LED drive unit that a plurality of LED crosstalks streams share ", this drive unit uses single linear adjuster or other controller and a multi-output current mirror, and this multi-output current mirror depends on hardly the DC input voltage source, depends on owing to the variation of the transistor that the semiconductor integrated technique causes or MOSFET, and depend on hardly variations in temperature hardly.The multi-output current mirror comprises a plurality of transistors or MOSFET, and each in them is integrated on the identical substrate, have identical wide-long raceway groove than and identical source electrode connect and be connected with grid.This integrated LED drive unit provides automatic current to share under the DC pattern, and or has minimum phase delay under the PWM pattern.This mirror image current mirror output comprises the grid common source transistor of a plurality of mirror images-altogether pair.Yet, the technical scheme of this invention is that utilization is integrated on the identical substrate, a plurality of transistors or the MOSFET of same structure, form the multi-output current mirror and realize flow equalizing function, this technical scheme is the sampling resistor of connecting again after the parallel connection of multi-path flow equalizing metal-oxide-semiconductor source electrode, can only change simultaneously by the value that changes sampling resistor like this electric current sum of LED multi-path string, lack flexibility, can not adapt to the coupling of the LED of different brightness shelves.
In addition, there is the gear problem in LED, and LED manufacturer can not only supply the LED of same brightness shelves, and the LED of different brightness gears must mate the different luminous consistency of LED electric current guarantee.And in producing, if the LED of every kind of brightness gear is removed to design the control board of different electric currents, not only waste time and energy and make mistakes easily, and can cause product to lack interchangeability, make troubles for the after-sale service of product.
The utility model content
The purpose of this utility model provides a kind of linear constant current current-sharing led drive circuit, have constant current, current-sharing, LED and divide the multi-functional of gear, PWM light modulation, satisfy the every actual demand in the automotive electronics illumination, reduce complexity and wrong probability in design and the production, enhance productivity.
The utility model solves the problems of the technologies described above the technical scheme that adopts:
A kind of linear constant current current-sharing led drive circuit, be used to the LED multi-path light emitting module that the drive current of equalization stable is provided, described LED multi-path light emitting module comprises at least 2 paths of LEDs strings, and each paths of LEDs string comprises respectively at least 1 LED element that is connected in series, and it is characterized in that:
Described led drive circuit comprises reference voltage unit, constant current feedback unit and multi-channel sampling current-sharing unit;
The reference voltage output terminal of described reference voltage unit is connected to the reference voltage input terminal of constant current feedback unit, and the output of described constant current feedback unit is connected to the input of described multi-channel sampling current-sharing unit;
Corresponding to each paths of LEDs string of LED multi-path light emitting module, described multi-channel sampling current-sharing unit arranges one tunnel constant current branch road; Described constant current branch road comprises one with constant flow element and a sampling resistor that is connected in series with constant flow element of the control utmost point, and the constant current output end of each branch road constant flow element is connected respectively to a corresponding paths of LEDs string; The control utmost point of all each branch road constant flow elements links together, and consists of the input of multi-channel sampling current-sharing unit; Being connected in series a little of each branch road constant flow element and sampling resistor links together by a feedback resistance respectively, is connected to the feedback signal input of described constant current feedback unit; The constant current control output end of constant current feedback unit is connected to the input of described multi-channel sampling current-sharing unit, consists of the Closed-loop Constant-current control loop.
A kind of better technical scheme of linear constant current current-sharing led drive circuit of the present utility model is characterized in that described reference voltage unit comprises the voltage stabilizing circuit that current-limiting resistance R2, voltage-stabiliser tube Z1 and diode D2 form; The output end of pressure-stabilizing of described voltage stabilizing circuit, be connected to the bleeder circuit that divider resistance R3 and R4 form, the dividing point of bleeder circuit consists of the reference voltage output terminal of described reference voltage unit, by the low pass filter that is formed by resistance R 5 and capacitor C 3, be connected to the reference voltage input terminal of described constant current feedback unit.
A kind of better technical scheme of linear constant current current-sharing led drive circuit of the present utility model, it is characterized in that described constant current feedback unit comprises operational amplifier A R1A, the in-phase input end of described operational amplifier A R1A, as the reference voltage input terminal of constant current feedback unit, be connected to described reference voltage unit; Each road current sample feedback end of described multi-channel sampling current-sharing unit respectively by described feedback resistance, is parallel-connected to the inverting input of described operational amplifier A R1A, consists of the feedback signal input of described constant current feedback unit; The output of described operational amplifier A R1A connects the low pass filter that is comprised of resistance R 8 and capacitor C 5, consists of the output of constant current feedback unit, is connected to the input of described multi-channel sampling current-sharing unit.
A kind of improved technical scheme of linear constant current current-sharing led drive circuit of the present utility model is characterized in that described constant flow element with the control utmost point is the power stage triode; The described control utmost point is the base stage of power stage triode, and the base stage of the power stage triode of each constant current branch road is connected in parallel, and consists of the input of described multi-channel sampling current-sharing unit; The collector electrode of each road power stage triode consists of one road constant current output end of multi-channel sampling current-sharing unit, is connected to a paths of LEDs string of LED multi-path light emitting module; The emitter of each road power stage triode is by described sampling resistor ground connection, being connected in series a little of the emitter of power stage triode and sampling resistor, link together by a feedback resistance respectively, be connected to the feedback signal input of described constant current feedback unit.
The another kind of improved technical scheme of linear constant current current-sharing led drive circuit of the present utility model is characterized in that described constant flow element with the control utmost point is the power stage metal-oxide-semiconductor; The described control utmost point is the grid of power stage metal-oxide-semiconductor, and the grid of the power stage metal-oxide-semiconductor of each constant current branch road is connected in parallel, and consists of the input of described multi-channel sampling current-sharing unit; The drain electrode of each road power stage metal-oxide-semiconductor consists of one road constant current output end of multi-channel sampling current-sharing unit, is connected to a paths of LEDs string of LED multi-path light emitting module; The source electrode of each road power stage metal-oxide-semiconductor is by described sampling resistor ground connection, being connected in series a little of the source electrode of power stage metal-oxide-semiconductor and sampling resistor, link together by a feedback resistance respectively, be connected to the feedback signal input of described constant current feedback unit.
A kind of further improved technical scheme of linear constant current current-sharing led drive circuit of the present utility model, it is characterized in that described constant current branch road is provided with the shunt resistance in parallel with constant flow element, one end of described shunt resistance is connected to described constant current output end, the other end of described shunt resistance be connected to constant flow element and sampling resistor be connected in series a little on.
A kind of preferred technical scheme of linear constant current current-sharing led drive circuit of the present utility model, it is characterized in that described led drive circuit also comprises PWM light modulation metal-oxide-semiconductor Q4, the external PWM signal input is connected to the grid of metal-oxide-semiconductor Q4, the source electrode pin ground connection of metal-oxide-semiconductor Q4, the drain electrode of metal-oxide-semiconductor Q4 is connected to the dividing point of divider resistance R3 and R4, pwm signal by light modulation metal-oxide-semiconductor Q4 grid, the reference voltage of control constant current feedback unit, change the conduction ratio of each road power component of multi-channel sampling current-sharing unit, the LED multi-path light emitting module is carried out the PWM light modulation.
The another kind of preferred technical scheme of linear constant current current-sharing led drive circuit of the present utility model, it is characterized in that described led drive circuit comprises that also LED divides gear resistance, after described LED divides gear resistance and resistance R 15 is connected, be connected in parallel with the divider resistance R3 of described reference voltage unit.
Another purpose of the present utility model provides a kind of circuit board structure of linear constant current current-sharing led drive circuit, can distinguish voluntarily LED brightness gear according to the circuit element parameter of LED wiring board, thereby need not change any parameter of any element on the control board, can automatically regulate the LED electric current according to the brightness gear of LED circuit onboard led, realize the height interchangeability of wiring board product.
The utility model solves the problems of the technologies described above the technical scheme that adopts:
A kind of printed circuit board structure for above-mentioned linear constant current current-sharing led drive circuit, described printed substrate comprises LED wiring board and control circuit board, it is characterized in that the described LED element that is connected in series channeling LED light emitting module, be installed on the described LED wiring board; The circuit element of described reference voltage unit, constant current feedback unit and multi-channel sampling current-sharing unit is installed on the described control circuit board, connects to form described led drive circuit; Described LED divides the resistance of gear resistance, is to match according to the brightness gear of the LED element of installing on the LED wiring board; Described LED divides gear resistance to be installed on the LED wiring board, is connected to reference voltage unit on the control circuit board by the step resistance link; Multi-channel sampling current-sharing unit on the control circuit board by the constant current output end, is connected to each the paths of LEDs string on the LED wiring board.
The beneficial effects of the utility model are:
1. linear constant current current-sharing led drive circuit of the present utility model, only use the electric current of a constant current feedback unit control LED multi-path string, have constant current, current-sharing, LED and divide the multi-functional of gear, PWM light modulation, can adapt to the inside and outside LED illumination of car and the alarm function requirement of various different automobile types, different purposes, satisfy the every actual demand in the automotive electronics illumination, the complexity that can greatly reduce the led drive circuit design and produce reduces wrong probability.
2. linear constant current current-sharing led drive circuit of the present utility model, no matter whether LED number on every string LED string equates, be connected on sampling resistor in each road sampling constant current branch road by setting, just the drive current that flows through this paths of LEDs string can be set, and keep constant current to drive, any paths of LEDs string or wherein any one LED element short circuit or open circuit, can not affect the drive current of other each paths of LEDs string; By shunt resistance in parallel on constant flow element, can in the high input voltage situation, shunt constant flow element, reduce power consumption and the heat of constant flow element, thereby can significantly improve the reliability of product and the flexibility of control.
3. linear constant current current-sharing led drive circuit of the present utility model, divide gear resistance by the LED that is arranged on the LED wiring board, distinguish voluntarily LED brightness gear, can automatically regulate the LED electric current according to the brightness gear of LED circuit onboard led, therefore, in production or maintenance process, need not change any parameter of any element on the control circuit board, can realize the height interchangeability of wiring board product, enhance productivity.
Description of drawings
Fig. 1 is the electrical schematic diagram of the linear constant current current-sharing of the utility model led drive circuit.
Among the figure, 100-LED multi-path light emitting module, the 200-reference voltage unit, 300-constant current feedback unit, 400-multi-channel sampling current-sharing unit, solid wire frame PCB1 represents the LED wiring board, solid wire frame PCB2 represents control circuit board.
Embodiment
In order to understand better technique scheme of the present utility model, describe in detail further below in conjunction with drawings and Examples.
Linear constant current current-sharing led drive circuit of the present utility model, be used to LED multi-path light emitting module 100 that the drive current of equalization stable is provided, LED multi-path light emitting module 100 comprises at least 2 paths of LEDs strings, and each paths of LEDs string comprises respectively at least 1 LED element that is connected in series.Be subjected to the restriction of operating voltage, LED number≤3 of usually connecting in each paths of LEDs string.In the embodiment shown in fig. 1, LED multi-path light emitting module 100 comprises 3 paths of LEDs strings, input voltage Vcc is connected to the positive pole of each paths of LEDs string through Anti-surging and the filter circuit of TVS pipe or transient voltage suppressor diode T1, capacitor C 1 and resistance R 1 composition by the LED+ end via anti-reverse diode D1.Among the figure, the first paths of LEDs string is composed in series by LED element LED1, LED2 and LED3, and its negative pole is connected to the LED-1 end; The second paths of LEDs string is composed in series by LED element LED4 and LED5, and its negative pole is connected to the LED-2 end; Third Road LED string only comprises LED element LED6, and its negative pole is connected to the LED-3 end.
Led drive circuit of the present utility model comprises reference voltage unit 200, constant current feedback unit 300 and multi-channel sampling current-sharing unit 400; The with dashed lines frame table shows above-mentioned unit in Fig. 1.
The reference voltage output terminal of reference voltage unit 200 (A point among Fig. 1), by the low pass filter that is formed by resistance R 5 and capacitor C 3, be connected to the reference voltage input terminal (A1 point among Fig. 1) of constant current feedback unit 300, the output of constant current feedback unit 300 is connected to the input (B point among Fig. 1) of multi-channel sampling current-sharing unit 400.
Corresponding to each paths of LEDs string of LED multi-path light emitting module 100, multi-channel sampling current-sharing unit 400 arranges one tunnel constant current branch road; Described constant current branch road comprises one with constant flow element Q1, Q2 and Q3 and sampling resistor Rs1, Rs2 or a Rs3 who is connected in series with constant flow element of the control utmost point, the constant current output end of each branch road constant flow element (F1 among Fig. 1, F2 and F3 point) is connected to a corresponding paths of LEDs string by LED-1, LED-2 and LED-3 end respectively; The control utmost point of all each branch road constant flow elements links together, and consists of the input (B point among Fig. 1) of multi-channel sampling current-sharing unit 400; Being connected in series a little of each branch road constant flow element and sampling resistor links together by feedback resistance Rf1, a Rf2 or Rf3 respectively, is connected to the feedback signal input (C point among Fig. 1) of described constant current feedback unit 300; The constant current control output end of constant current feedback unit 300 is connected to the input (B point among Fig. 1) of described multi-channel sampling current-sharing unit 400, consists of the Closed-loop Constant-current control loop.
By sampling resistor Rs1, Rs2 or the Rs3 of each constant current branch road are set, the utility model can be controlled respectively the electric current of each paths of LEDs string, take embodiment shown in Figure 1 as example, Rs1=Rs2=Rs3 can be set, make the electric current of 3 paths of LEDs strings identical, also Rs1 ≠ Rs2 ≠ Rs3 can be set, make in the 3 paths of LEDs strings and flow through different electric currents, therefore linear constant current current-sharing led drive circuit of the present utility model is compared with existing technical scheme, has greater flexibility.
In the embodiment of of the present utility model linear constant current current-sharing led drive circuit shown in Figure 1, reference voltage unit 200 comprises the voltage stabilizing circuit that current-limiting resistance R2, voltage-stabiliser tube Z1 and diode D2 form; Input voltage Vcc is connected to current-limiting resistance R2 through anti-reverse diode D1, current-limiting resistance R2 is connected with the negative pole of voltage-stabiliser tube Z1, form the output end of pressure-stabilizing D of voltage stabilizing circuit, the positive pole of voltage-stabiliser tube Z1 is connected with the positive pole of diode D2, and the negative pole of diode D2 is connected to ground.By the series connection of voltage-stabiliser tube Z1 and diode D2, can offset warm impact of floating reference voltage under the different temperatures.The output end of pressure-stabilizing D of voltage stabilizing circuit, be connected to the bleeder circuit that divider resistance R3 and R4 form, the dividing point of bleeder circuit (A point among Fig. 1) consists of the reference voltage output terminal of reference voltage unit 200, by the low pass filter that is formed by resistance R 5 and capacitor C 3, be connected to the reference voltage input terminal (A1 point among Fig. 1) of constant current feedback unit 300.
In the embodiment of of the present utility model linear constant current current-sharing led drive circuit shown in Figure 1, constant current feedback unit 300 comprises operational amplifier A R1A, the in-phase input end of operational amplifier A R1A, reference voltage input terminal (A1 point among Fig. 1) as the constant current feedback unit is connected to reference voltage unit 200; Each road current sample feedback end of multi-channel sampling current-sharing unit 400 respectively by feedback resistance Rf1, Rf2, Rf3, is parallel-connected to the inverting input of described operational amplifier A R1A, consists of the feedback signal input of constant current feedback unit 300; The output of operational amplifier A R1A connects the low pass filter that is comprised of resistance R 8 and capacitor C 5, consists of the output of constant current feedback unit 300, is connected to the input (B point among Fig. 1) of multi-channel sampling current-sharing unit 400.
In the embodiment of of the present utility model linear constant current current-sharing led drive circuit shown in Figure 1, be power stage triode Q1, Q2 and Q3 with the constant flow element of controlling the utmost point; The described control utmost point is the base stage of power stage triode, and power stage triode Q1, the Q2 of each constant current branch road and the base stage of Q3 are connected in parallel, and consists of the input of described multi-channel sampling current-sharing unit 400; The collector electrode of each road power stage triode Q1, Q2 or Q3, consist of one road constant current output end (F1 among Fig. 1, F2 and F3 point) of multi-channel sampling current-sharing unit 400, by LED-1, LED-2 and LED-3 end, be connected to a paths of LEDs string of LED multi-path light emitting module 100; The emitter of each road power stage triode Q1, Q2, Q3, by described sampling resistor Rs1, Rs2, Rs3 ground connection, the emitter of power stage triode Q1, Q2, Q3 and sampling resistor Rs1, Rs2, Rs3 are connected in series a little, link together by feedback resistance Rf1, Rf2, Rf3 respectively, be connected to the feedback signal input of described constant current feedback unit 300, namely the inverting input of operational amplifier A R1A (C point among Fig. 1).This circuit structure of the present utility model has been realized controlling simultaneously the electric current that flows through on the LED multi-path electric current string with the constant current feedback unit 300 of an operational amplifier composition, no matter whether LED the number of connecting in each paths of LEDs string equates.
Although constant flow element Q1, Q2 and Q3 with the control utmost point among the embodiment shown in Figure 1 are the power stage triodes, linear constant current current-sharing led drive circuit of the present utility model equally also can adopt power MOS pipe to form sampling constant current branch road.In the situation that adopts power MOS pipe, the control utmost point of constant flow element is the grid of power stage metal-oxide-semiconductor, and the grid of the power stage metal-oxide-semiconductor of each constant current branch road is connected in parallel, and consists of the input of described multi-channel sampling current-sharing unit; The drain electrode of each road power stage metal-oxide-semiconductor consists of one road constant current output end of multi-channel sampling current-sharing unit, is connected to a paths of LEDs string of LED multi-path light emitting module 100; The source electrode of each road power stage metal-oxide-semiconductor is by described sampling resistor Rs1, Rs2, Rs3 ground connection, the source electrode of power stage metal-oxide-semiconductor and sampling resistor Rs1, Rs2, Rs3 are connected in series a little, link together by feedback resistance Rf1, Rf2, Rf3 respectively, be connected to the feedback signal input of described constant current feedback unit 300, namely the inverting input of operational amplifier A R1A (C point among Fig. 1).
In the embodiment of of the present utility model linear constant current current-sharing led drive circuit shown in Figure 1, each constant current branch road is provided with the shunt resistance R41 in parallel with constant flow element, R42, R43, constant flow element is power stage triode Q1 in this embodiment, Q2, Q3, shunt resistance R41, the end of R42 or R43 is connected to the described constant current output end (F1 among Fig. 1, F2 and F3 point), namely be power stage triode Q1, Q2, the collector electrode of Q3, shunt resistance R41, the other end of R42 or R43, be connected to constant flow element and sampling resistor be connected in series a little on, namely be power stage triode Q1, Q2, the emitter of Q3.Shunt resistance R41, R42, the R43 of parallel connection between the collector and emitter of power stage triode, its effect is in the high input voltage situation, power stage triode as constant flow element is shunted, thereby reduced power consumption and the heat of constant flow element in the high input voltage situation.
In the embodiment of of the present utility model linear constant current current-sharing led drive circuit shown in Figure 1, led drive circuit also comprises PWM light modulation metal-oxide-semiconductor Q4, the external PWM signal input is connected to the grid of metal-oxide-semiconductor Q4, the source electrode pin ground connection of metal-oxide-semiconductor Q4, the drain electrode of metal-oxide-semiconductor Q4 is connected to the dividing point A of divider resistance R3 and R4.Existing PWM light regulating technology adopts the direct power ratio control output element of pwm signal to realize the PWM light modulation usually, be different from existing PWM light regulating technology, led drive circuit of the present utility model is by the pwm signal of light modulation metal-oxide-semiconductor Q4 grid, the reference voltage of control constant current feedback unit 300, thereby change simultaneously the conduction ratio of multi-channel sampling current-sharing unit 400 each road power component, each paths of LEDs string of LED multi-path light emitting module 100 is realized the PWM light modulation simultaneously.
According to embodiment shown in Figure 1, linear constant current current-sharing led drive circuit of the present utility model comprises that also LED divides gear resistance R bin, after LED divides gear resistance R bin and resistance R 15 is connected, is connected in parallel with the divider resistance R3 of reference voltage unit 200.In the embodiment shown in fig. 1, use solid wire frame to schematically illustrate the printed circuit board structure that is used for above-mentioned linear constant current current-sharing led drive circuit, in this embodiment, printed substrate is divided into LED wiring board PCB1 and control circuit board PCB2, the solid wire frame representation LED wiring board PCB1 on Fig. 1 top, the LED element of LED multi-path light emitting module 100 is installed on the LED wiring board PCB1, is connected in series to form 3 paths of LEDs strings; The solid wire frame representation control circuit board PCB2 on Fig. 1 top, the circuit element of reference voltage unit 200, constant current feedback unit 300 and multi-channel sampling current-sharing unit 400 is installed on the control circuit board PCB2, connects to form led drive circuit of the present utility model; Described LED divides the resistance of gear resistance, is to match according to the brightness gear of the upper LED element of installing of LED wiring board PCB1; LED divides gear resistance R bin to be installed on the LED wiring board PCB1, and by step resistance link Rbin+ and Rbin-, LED divides gear resistance R bin to be connected to reference voltage unit 200 on the control circuit board PCB2; Multi-channel sampling current-sharing unit 400 on the control circuit board PCB2 by constant current output end LED-1, LED-2 and LED-3, is connected to each the paths of LEDs string on the LED wiring board PCB1.So, the utility model can be by changing the circuit board structure of linear constant current current-sharing led drive circuit, realization is distinguished LED brightness gear voluntarily according to the circuit element parameter of LED wiring board PCB1, thereby need not change any parameter of the upper any element of control circuit board PCB2, can automatically regulate the LED electric current according to the brightness gear of the upper LED of LED wiring board PCB1, realize the height interchangeability of wiring board product.
Those of ordinary skill in the art will be appreciated that; above embodiment illustrates the technical solution of the utility model; and be not to be used as restriction of the present utility model; any variation, modification of the above embodiment being done based on connotation of the present utility model all will drop in the protection range of claim of the present utility model.

Claims (9)

1. linear constant current current-sharing led drive circuit, be used to the LED multi-path light emitting module that the drive current of equalization stable is provided, described LED multi-path light emitting module comprises at least 2 paths of LEDs strings, and each paths of LEDs string comprises respectively at least 1 LED element that is connected in series, and it is characterized in that:
Described led drive circuit comprises reference voltage unit, constant current feedback unit and multi-channel sampling current-sharing unit;
The reference voltage output terminal of described reference voltage unit is connected to the reference voltage input terminal of constant current feedback unit, and the output of described constant current feedback unit is connected to the input of described multi-channel sampling current-sharing unit;
Corresponding to each paths of LEDs string of LED multi-path light emitting module, described multi-channel sampling current-sharing unit arranges one tunnel constant current branch road; Described constant current branch road comprises one with constant flow element and a sampling resistor that is connected in series with constant flow element of the control utmost point, and the constant current output end of each branch road constant flow element is connected respectively to a corresponding paths of LEDs string; The control utmost point of all each branch road constant flow elements links together, and consists of the input of multi-channel sampling current-sharing unit; Being connected in series a little of each branch road constant flow element and sampling resistor links together by a feedback resistance respectively, is connected to the feedback signal input of described constant current feedback unit; The constant current control output end of constant current feedback unit is connected to the input of described multi-channel sampling current-sharing unit, consists of the Closed-loop Constant-current control loop.
2. linear constant current current-sharing led drive circuit according to claim 1 is characterized in that described reference voltage unit comprises the voltage stabilizing circuit that current-limiting resistance R2, voltage-stabiliser tube Z1 and diode D2 form; The output end of pressure-stabilizing of described voltage stabilizing circuit, be connected to the bleeder circuit that divider resistance R3 and R4 form, the dividing point of bleeder circuit consists of the reference voltage output terminal of described reference voltage unit, by the low pass filter that is formed by resistance R 5 and capacitor C 3, be connected to the reference voltage input terminal of described constant current feedback unit.
3. linear constant current current-sharing led drive circuit according to claim 1, it is characterized in that described constant current feedback unit comprises operational amplifier A R1A, the in-phase input end of described operational amplifier A R1A, as the reference voltage input terminal of constant current feedback unit, be connected to described reference voltage unit; Each road current sample feedback end of described multi-channel sampling current-sharing unit respectively by described feedback resistance, is parallel-connected to the inverting input of described operational amplifier A R1A, consists of the feedback signal input of described constant current feedback unit; The output of described operational amplifier A R1A connects the low pass filter that is comprised of resistance R 8 and capacitor C 5, consists of the output of constant current feedback unit, is connected to the input of described multi-channel sampling current-sharing unit.
4. linear constant current current-sharing led drive circuit according to claim 1 is characterized in that described constant flow element with the control utmost point is the power stage triode; The described control utmost point is the base stage of power stage triode, and the base stage of the power stage triode of each constant current branch road is connected in parallel, and consists of the input of described multi-channel sampling current-sharing unit; The collector electrode of each road power stage triode consists of one road constant current output end of multi-channel sampling current-sharing unit, is connected to a paths of LEDs string of LED multi-path light emitting module; The emitter of each road power stage triode is by described sampling resistor ground connection, being connected in series a little of the emitter of power stage triode and sampling resistor, link together by a feedback resistance respectively, be connected to the feedback signal input of described constant current feedback unit.
5. linear constant current current-sharing led drive circuit according to claim 1 is characterized in that described constant flow element with the control utmost point is the power stage metal-oxide-semiconductor; The described control utmost point is the grid of power stage metal-oxide-semiconductor, and the grid of the power stage metal-oxide-semiconductor of each constant current branch road is connected in parallel, and consists of the input of described multi-channel sampling current-sharing unit; The drain electrode of each road power stage metal-oxide-semiconductor consists of one road constant current output end of multi-channel sampling current-sharing unit, is connected to a paths of LEDs string of LED multi-path light emitting module; The source electrode of each road power stage metal-oxide-semiconductor is by described sampling resistor ground connection, being connected in series a little of the source electrode of power stage metal-oxide-semiconductor and sampling resistor, link together by a feedback resistance respectively, be connected to the feedback signal input of described constant current feedback unit.
6. linear constant current current-sharing led drive circuit according to claim 1, it is characterized in that described constant current branch road is provided with the shunt resistance of constant flow element parallel connection, one end of described shunt resistance is connected to described constant current output end, the other end of described shunt resistance be connected to constant flow element and sampling resistor be connected in series a little on.
7. linear constant current current-sharing led drive circuit according to claim 1, it is characterized in that described led drive circuit also comprises PWM light modulation metal-oxide-semiconductor Q4, the external PWM signal input is connected to the grid of metal-oxide-semiconductor Q4, the source electrode pin ground connection of metal-oxide-semiconductor Q4, the drain electrode of metal-oxide-semiconductor Q4 is connected to the dividing point of divider resistance R3 and R4, pwm signal by light modulation metal-oxide-semiconductor Q4 grid, the reference voltage of control constant current feedback unit, change the conduction ratio of each road power component of multi-channel sampling current-sharing unit, the LED multi-path light emitting module is carried out the PWM light modulation.
8. according to claim 1 to 7 to the described linear constant current current-sharing led drive circuit of arbitrary claim, it is characterized in that described led drive circuit comprises that also LED divides gear resistance, after described LED divides gear resistance and resistance R 15 is connected, be connected in parallel with the divider resistance R3 of described reference voltage unit.
9. printed circuit board structure that is used for linear constant current current-sharing led drive circuit claimed in claim 8, described printed substrate comprises LED wiring board and control circuit board, it is characterized in that the described LED element that is connected in series channeling LED light emitting module, be installed on the described LED wiring board; The circuit element of described reference voltage unit, constant current feedback unit and multi-channel sampling current-sharing unit is installed on the described control circuit board, connects to form described led drive circuit; Described LED divides the resistance of gear resistance, is to match according to the brightness gear of the LED element of installing on the LED wiring board; Described LED divides gear resistance to be installed on the LED wiring board, is connected to reference voltage unit on the control circuit board by the step resistance link; Multi-channel sampling current-sharing unit on the control circuit board by the constant current output end, is connected to each the paths of LEDs string on the LED wiring board.
CN 201220565732 2012-10-31 2012-10-31 Linear constant current current sharing LED driving circuit and circuit board structure thereof Withdrawn - After Issue CN202857100U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN 201220565732 CN202857100U (en) 2012-10-31 2012-10-31 Linear constant current current sharing LED driving circuit and circuit board structure thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN 201220565732 CN202857100U (en) 2012-10-31 2012-10-31 Linear constant current current sharing LED driving circuit and circuit board structure thereof

Publications (1)

Publication Number Publication Date
CN202857100U true CN202857100U (en) 2013-04-03

Family

ID=47988241

Family Applications (1)

Application Number Title Priority Date Filing Date
CN 201220565732 Withdrawn - After Issue CN202857100U (en) 2012-10-31 2012-10-31 Linear constant current current sharing LED driving circuit and circuit board structure thereof

Country Status (1)

Country Link
CN (1) CN202857100U (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102905443A (en) * 2012-10-31 2013-01-30 上海小糸车灯有限公司 Linear constant-current and current-sharing LED drive circuit and circuit board structure thereof
CN103796387A (en) * 2013-12-27 2014-05-14 陈俞好 LED drive device, battery charger and drive control circuit of LED drive device
CN106304477A (en) * 2016-08-17 2017-01-04 上海小糸车灯有限公司 A kind of LED load equalizing control circuit and control method
CN106937432A (en) * 2015-12-31 2017-07-07 赛尔富电子有限公司 One kind is used for numerically controlled light adjusting circuit
CN108882431A (en) * 2017-05-08 2018-11-23 群光电能科技股份有限公司 Power supply device
US20190268988A1 (en) * 2018-02-27 2019-08-29 Valeo Vision Light module for a motor vehicle comprising a plurality of light source branches

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102905443A (en) * 2012-10-31 2013-01-30 上海小糸车灯有限公司 Linear constant-current and current-sharing LED drive circuit and circuit board structure thereof
CN102905443B (en) * 2012-10-31 2014-12-10 上海小糸车灯有限公司 Linear constant-current and current-sharing LED drive circuit and circuit board structure thereof
CN103796387A (en) * 2013-12-27 2014-05-14 陈俞好 LED drive device, battery charger and drive control circuit of LED drive device
CN106937432A (en) * 2015-12-31 2017-07-07 赛尔富电子有限公司 One kind is used for numerically controlled light adjusting circuit
CN106304477A (en) * 2016-08-17 2017-01-04 上海小糸车灯有限公司 A kind of LED load equalizing control circuit and control method
CN106304477B (en) * 2016-08-17 2017-10-03 上海小糸车灯有限公司 A kind of LED load equalizing control circuit and control method
CN108882431A (en) * 2017-05-08 2018-11-23 群光电能科技股份有限公司 Power supply device
TWI662391B (en) * 2017-05-08 2019-06-11 群光電能科技股份有限公司 Power supplying device
US10326360B2 (en) 2017-05-08 2019-06-18 Chicony Power Technology Co., Ltd. Power supplying device
CN108882431B (en) * 2017-05-08 2020-04-24 群光电能科技股份有限公司 Power supply device
US20190268988A1 (en) * 2018-02-27 2019-08-29 Valeo Vision Light module for a motor vehicle comprising a plurality of light source branches
US10917949B2 (en) * 2018-02-27 2021-02-09 Valeo Vision Light module for a motor vehicle comprising a plurality of light source branches

Similar Documents

Publication Publication Date Title
CN102905443B (en) Linear constant-current and current-sharing LED drive circuit and circuit board structure thereof
CN202857100U (en) Linear constant current current sharing LED driving circuit and circuit board structure thereof
EP3228159B1 (en) Current splitter for led lighting system
CN102318440B (en) Many LED control
CN102917508B (en) Multi-path constant current LED drive circuit with protection function and circuit board structure thereof
CN203057594U (en) Multipath constant current LED drive circuit with protection function and circuit board structure thereof
JP5038982B2 (en) LED drive device
CN109788614A (en) Lamps apparatus for vehicle and its lighting circuit, current driver circuits
CN101959352A (en) LED driving circuit with LED short-circuit protection
CN103249218B (en) LED drive circuit, driving method and Vehicle lamp
CN102573213A (en) LED (Light Emitting Diode) dimming system
CN104883789A (en) Constant-current control circuit for LED display device and display device
CN201742604U (en) Multi-path LED current-equalizing control circuit
CN102510598A (en) Current-adjustable multi-channel LED (Light-emitting Diode) drive control system and control method
CN102271440B (en) Current-sharing control circuit for multi-path light-emitting diode (LED)
CN101813260B (en) LED lamp device and PWM (Pulse Width Modulation) direct current supply control circuit
CN113271700B (en) Lighting system
CN102316647A (en) LED lamp color temperature adjusting driver
CN209593813U (en) OLED light source drive control circuit and OLED luminaire
CN204598391U (en) A kind of circuit simultaneously controlling LED brightness, colour temperature
CN209930560U (en) LED drive circuit and car light and car that have it
CN201328203Y (en) Dimmable three-channel large-power LED constant-flow driver module
JP7189598B2 (en) lighting equipment
CN101799130A (en) Illumination device with automatic dimming function
CN201726566U (en) Led lamp device

Legal Events

Date Code Title Description
C14 Grant of patent or utility model
GR01 Patent grant
AV01 Patent right actively abandoned

Granted publication date: 20130403

Effective date of abandoning: 20141210

RGAV Abandon patent right to avoid regrant