CN203057594U - Multipath constant current LED drive circuit with protection function and circuit board structure thereof - Google Patents
Multipath constant current LED drive circuit with protection function and circuit board structure thereof Download PDFInfo
- Publication number
- CN203057594U CN203057594U CN201220565743XU CN201220565743U CN203057594U CN 203057594 U CN203057594 U CN 203057594U CN 201220565743X U CN201220565743X U CN 201220565743XU CN 201220565743 U CN201220565743 U CN 201220565743U CN 203057594 U CN203057594 U CN 203057594U
- Authority
- CN
- China
- Prior art keywords
- constant current
- led
- unit
- circuit
- input
- 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.)
- Expired - Lifetime
Links
- 238000005070 sampling Methods 0.000 claims abstract description 62
- 238000001514 detection method Methods 0.000 claims abstract description 33
- 239000004065 semiconductor Substances 0.000 claims description 25
- 238000003745 diagnosis Methods 0.000 claims description 16
- 230000000087 stabilizing effect Effects 0.000 claims description 11
- AGCPZMJBXSCWQY-UHFFFAOYSA-N 1,1,2,3,4-pentachlorobutane Chemical compound ClCC(Cl)C(Cl)C(Cl)Cl AGCPZMJBXSCWQY-UHFFFAOYSA-N 0.000 claims description 8
- 239000003990 capacitor Substances 0.000 claims description 8
- 239000003381 stabilizer Substances 0.000 claims description 5
- MINPZZUPSSVGJN-UHFFFAOYSA-N 1,1,1,4,4,4-hexachlorobutane Chemical compound ClC(Cl)(Cl)CCC(Cl)(Cl)Cl MINPZZUPSSVGJN-UHFFFAOYSA-N 0.000 claims description 2
- 101150049492 DVR gene Proteins 0.000 claims description 2
- 238000000034 method Methods 0.000 abstract description 7
- 238000005516 engineering process Methods 0.000 description 5
- 206010039203 Road traffic accident Diseases 0.000 description 3
- 238000004020 luminiscence type Methods 0.000 description 3
- 239000007787 solid Substances 0.000 description 3
- 238000005286 illumination Methods 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 230000001052 transient effect Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000012536 packaging technology Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000001012 protector Effects 0.000 description 1
- 230000011664 signaling Effects 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
Images
Classifications
-
- 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
- Y02B20/40—Control techniques providing energy savings, e.g. smart controller or presence detection
Landscapes
- Circuit Arrangement For Electric Light Sources In General (AREA)
Abstract
The utility model provides a multipath constant current LED drive circuit with a protection function and a circuit board structure thereof, and relates to a drive circuit used for vehicle LED lighting devices and distribution of components thereof. The drive circuit comprises a reference voltage unit, a constant current feedback unit, a multipath sampling current sharing unit, and an LED string fail safe unit. The multipath sampling current sharing unit is corresponding connected with each LED string of a multipath LED lighting module. Each path of current sampling feedback terminal is connected with a feedback signal input terminal of the constant current feedback unit. Corresponding to each path of LED string, the multipath sampling current sharing unit is provided with a constant current branch circuit. The LED string fail safe unit comprises a multipath failure detection circuit, and a controlled electronic switch. Each detection output terminal of the multipath failure detection circuit is connected with a control electrode of the controlled electronic switch by a disjunction gate. The LED drive circuit also comprises an LED protection unit which uses a method of power reduction lighting but not stopping lighting to realize overvoltage protection and overtemperature protection, so that road safety is ensured while the protection function is achieved.
Description
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 that response speed is fast, low-power consumption, energy-conservation, 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 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 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, and therefore LED is luminous constant if desired, and 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 adjustable 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 under 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 LED coupled in series is generally below 3.As needing to need multi-channel linear adjustable type circuit to drive the LED multi-path string usually when driven greater than 3 LED, to guarantee that a number in every paths of LEDs string is smaller 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 a single output constant-current source and multiplex output circuit, it is characterized in that described each output circuit comprises a flow equalizing circuit, an equalizing control circuit and the load of being 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 flow equalizing circuit 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 flow equalizing circuit, control the size of every road electric current then, realize current-sharing.Though 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 flow equalizing circuit and an equalizing control circuit, circuit structure complexity, not only improved cost, the increase of circuit elements device also can reduce reliability.
In addition, the LED control unit applies to the automobile lamp field, and the heat that take place easily in whole driving life that LED opens circuit, vehicle body overvoltage, car engine starts to produce causes LED load overtemperature and shortened the situations such as useful life of LED.And in each main engine plants' standard electric control unit also there are test requirements documents such as load cut-off protection, overvoltage protection.When driving, cause some angle of light fixture not visible if take place single LEDs to lose efficacy, traffic accident just very easily takes place.China's utility model patent " PWM formula adjustable brightness LED tail light for vehicle module " (Chinese utility model patent number: ZL200820057785.6 Granted publication number: CN201220626Y) disclose a kind of PWM formula adjustable brightness LED tail light for vehicle module, comprised substrate, LED luminescence unit, constant current driving unit and fault detection unit; By being set, described fault detection unit detects resistance in each one of branch road series connection of described LED luminescence unit, become the electric current that detects each branch road with gate cell to come the fault of detection system with diode configuration, report an error when mistake appears in system, for automobile BCM unit, make the driver when driving, know the working condition of taillight, can reduce the traffic accident that causes because not finding the fault of taillight; Simultaneously by described PWM generation unit is set, clock chip U3 by described PWM generation unit produces fixing PWM pulsewidth, be transferred to described constant current driving unit and effectively regulate the brightness of LED, brightness during effectively control braking/driving, avoid causing described LED luminescence unit not work/overcurrent damage owing to vehicle-mounted brownout/too high, driving/brake signal is better differentiated.Yet, though the technical scheme of this utility model is provided with the LED fault detection unit, but there is following defective: 1. when finding that single of LED lost efficacy, fault detection unit is not handled fault, for example turn-off all LED, give body of a motor car control unit BCM and just send an alarm signal, this needs, and BCM reserves an alarm signal mouth to light fixture, has taken the port resource of BCM more.2. the technical scheme of this utility model lacks the function to overheat protector and the overvoltage protection of LED.
The utility model content
The purpose of this utility model provides a kind of multiple constant current led drive circuit with defencive function, can detect and judge that single LEDs lost efficacy provide constant current to drive for LED multi-path when; Too high when LED light fixture working temperature, when perhaps supply power voltage is too high, can provide the function of excess temperature overvoltage protection for LED.
The utility model solves the problems of the technologies described above the technical scheme that adopts:
A kind of multiple constant current led drive circuit with defencive function; 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 at least 1 LED coupled in series element respectively, it is characterized in that:
Described led drive circuit comprises reference voltage unit, constant current feedback unit, multi-channel sampling current-sharing unit and LED string fail safe 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 that has constant flow element and a sampling resistor that is connected in series with constant flow element of controlling the utmost point, and the constant current output 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 constitutes 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, constitutes closed loop constant current control loop;
Described LED string fail safe unit comprises multichannel failure detection circuit and controllable electronic switch; Each paths of LEDs string corresponding to the LED multi-path light emitting module, described multichannel failure detection circuit arranges one and detects input and a detection output, each of multichannel failure detection circuit detects input, and correspondence is connected to the constant current output that connects with this paths of LEDs polyphone; Each of multichannel failure detection circuit detects output, is connected to the control utmost point of described controllable electronic switch by OR circuit, and described controllable electronic switch is formed controlled grounded circuit between the output end of pressure-stabilizing of described voltage stabilizing circuit and earth terminal.
A kind of preferable technical scheme with multiple constant current led drive circuit of defencive function of the present utility model is characterized in that described reference voltage unit comprises the voltage stabilizing circuit that current-limiting resistance R2 and voltage-stabiliser tube Z1 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 constitutes the reference voltage output terminal of described reference voltage unit, by the low pass filter of being 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 with multiple constant current led drive circuit of defencive function 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, constitutes the feedback signal input of described constant current feedback unit; The output of described operational amplifier A R1A connects the low pass filter of being made up of resistance R 8 and capacitor C 5, constitutes the output of constant current feedback unit, is connected to the input of described multi-channel sampling current-sharing unit.
A kind of optimized technical scheme with multiple constant current led drive circuit of defencive function of the present utility model is characterized in that the described constant flow element of controlling the utmost point that has is the power output triode; The described control utmost point is the base stage of power output triode, and the base stage of the power output triode of each constant current branch road is connected in parallel, and constitutes the input of described multi-channel sampling current-sharing unit; The collector electrode of each road power output triode constitutes one tunnel constant current output 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 output triode is by described sampling resistor ground connection, being connected in series a little of the emitter of power output triode and sampling resistor, link together by a feedback resistance respectively, be connected to the feedback signal input of described constant current feedback unit.
Another kind of optimized technical scheme with multiple constant current led drive circuit of defencive function of the present utility model is characterized in that the described constant flow element of controlling the utmost point that has is power output mos pipe; The described control utmost point is the grid of power output mos pipe, and the grid of the power output mos pipe of each constant current branch road is connected in parallel, and constitutes the input of described multi-channel sampling current-sharing unit; The drain electrode of each road power output mos pipe constitutes one tunnel constant current output 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 output mos pipe is by described sampling resistor ground connection, being connected in series a little of the source electrode of power output mos pipe 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 improved technical scheme with multiple constant current led drive circuit of defencive function of the present utility model, each road that it is characterized in that described multichannel failure detection circuit comprises a diagnosis triode, the base stage base stage current-limiting resistance of connecting of diagnosis triode, constitute described detection input, correspondence is connected to described constant current output; The grounded emitter of diagnosis triode, the collector electrode of diagnosis triode is connected to the positive pole of LED through pull-up resistor, and the tie point of collector electrode and pull-up resistor constitutes described detection output.
Another kind of improved technical scheme with multiple constant current led drive circuit of defencive function of the present utility model, it is characterized in that led drive circuit also comprises the LED protected location, described LED protected location comprises protection control circuit and overvoltage sample circuit, described protection control circuit is made up of resistance R 15, metal-oxide-semiconductor Q7, the grid of metal-oxide-semiconductor Q7 constitutes the sampled signal input of protection control circuit, the source ground of metal-oxide-semiconductor Q7, the drain electrode of metal-oxide-semiconductor Q7 is connected to the reference voltage output terminal of reference voltage unit through resistance R 15; Described overvoltage sample circuit is the bleeder circuit that resistance R 16 and R21 form, and input voltage Vcc is connected to described sampled signal input after resistance R 16 and R21 dividing potential drop.
A kind of further improved technical scheme with multiple constant current led drive circuit of defencive function of the present utility model; it is characterized in that the LED protected location also comprises the overtemperature sample circuit; described overtemperature sample circuit is made up of resistance R 18 and thermistor Rt; described thermistor Rt is installed on the LED wiring board; the end of thermistor Rt is connected to input voltage Vcc, and the other end of thermistor Rt is connected to the sampled signal input of described LED protected location through resistance R 18.
The beneficial effects of the utility model are:
1. the multiple constant current led drive circuit with defencive function 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 influence the drive current of other each paths of LEDs string, can significantly improve the flexibility of reliability of products and control.
2. the multiple constant current led drive circuit with defencive function of the present utility model has for single LEDs failure diagnosis warning function, and having overcome prior art can only be after each paths of LEDs string all damages, could be to the problem of the Failure Alarm of whole LED light emitting module.The utility model is in the work loop that all each paths of LEDs strings take place to cut off when single LEDs lost efficacy, and the electric current that automobile body B CM only need monitor on the power line of power supply can be reported to the police, and does not need the resource of an alarming line of additional allocation.
3. the overvoltage protection with multiple constant current led drive circuit of defencive function of the present utility model; be different from existing over-voltage protection technology scheme; not when overvoltage, to cut off circuit fully that the LED light fixture is stopped is luminous; but make the LED light fixture fall power light-emitting by reducing electric current and power, thereby the fail safe when having guaranteed burst vehicle body overtension situation in the driving process.
4. the multiple constant current led drive circuit with defencive function of the present utility model adopts to fall power light-emitting rather than stop luminous mode and realizes overtemperature prote, can guarantee travel safety when prolonging the life-span of LED under the high temperature environment for use.
Description of drawings
Fig. 1 is the electrical schematic diagram that the utlity model has the multiple constant current led drive circuit of defencive function.
Among the figure, 100-LED multi-path light emitting module, 200-reference voltage unit; 300-constant current feedback unit; 400-multi-channel sampling current-sharing unit, 500-LED goes here and there fail safe unit (comprising 500a-multichannel failure detection circuit and 500b-controllable electronic switch), the 700-LED protected location.With solid wire frame representation LED wiring board PCB1, the part outside the solid wire frame is control circuit board PCB2 among Fig. 1.
Embodiment
In order to understand technique scheme of the present utility model better, describe in detail further below in conjunction with drawings and Examples.
Multiple constant current led drive circuit with defencive function 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 at least 1 LED coupled in series element respectively.Be subjected to the restriction of operating voltage, usually LED number≤3 of connecting in each paths of LEDs string.
Led drive circuit of the present utility model comprises reference voltage unit 200, constant current feedback unit 300, multi-channel sampling current-sharing unit 400 and LED string fail safe unit 500; The with dashed lines frame table shows above-mentioned each unit in Fig. 1, and wherein LED string fail safe unit 500 is divided into 500a and 500b two parts.
The reference voltage output terminal of reference voltage unit 200 (A point among Fig. 1), by the low pass filter of being 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 that has constant flow element Q1, Q2 and Q3 and sampling resistor Rs1, Rs2 or a Rs3 who is connected in series with constant flow element who controls the utmost point, the constant current output of each branch road constant flow element (F1 among Fig. 1, F2 and F3 point) 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 constitutes 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, constitutes closed loop constant current control loop.
LED string fail safe unit 500 comprises that multichannel failure detection circuit 500a and controllable electronic switch 500b form; Each paths of LEDs string corresponding to LED multi-path light emitting module 100, multichannel failure detection circuit 500a arranges one and detects input and a detection output, each of multichannel failure detection circuit 500a detects input, and correspondence is connected to constant current output F1, F2 or the F3 that connects with this paths of LEDs polyphone; Each of multichannel failure detection circuit 500a detects output, is connected to the control utmost point of controllable electronic switch by OR circuit, and described controllable electronic switch is formed controlled grounded circuit between the output end of pressure-stabilizing of described voltage stabilizing circuit and earth terminal; If any LEDs element in any paths of LEDs string opens circuit, the output high level of described OR circuit makes the controllable electronic switch conducting, and the output end of pressure-stabilizing of voltage stabilizing circuit is connected to earth terminal.
In the embodiment shown in fig. 1, LED multi-path light emitting module 100 comprises 3 paths of LEDs strings, input voltage Vcc suppresses anti-surge and the filter circuit that diode T1, capacitor C 1 and resistance R 1 are formed through TVS pipe or transient voltage, is connected to the positive pole of each paths of LEDs string by anti-reverse diode D1.Among the figure, the first paths of LEDs string is composed in series by LED element LED11, LED12 and LED13, and its negative pole is connected to constant current output F1; The second paths of LEDs string is composed in series by LED element LED21, LED22 and LED23, and its negative pole is connected to constant current output F2; Third Road LED string is composed in series by LED element LED31, LED32 and LED33, and its negative pole is connected to constant current output F3.
By sampling resistor Rs1, Rs2 or the Rs3 of each constant current branch road are set; the utility model can be controlled the electric current of each paths of LEDs string respectively; be example with embodiment shown in Figure 1; 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 the multiple constant current led drive circuit with defencive function of the present utility model is compared with existing technical scheme, has greater flexibility.
In the embodiment of multiple constant current led drive circuit with defencive function of the present utility model shown in Figure 1, reference voltage unit 200 comprises the voltage stabilizing circuit that current-limiting resistance R2 and voltage-stabiliser tube Z1 form; Input voltage Vcc is connected to current-limiting resistance R2 through anti-reverse diode D1, and current-limiting resistance R2 is connected with the negative pole of voltage-stabiliser tube Z1, forms the output end of pressure-stabilizing D of voltage stabilizing circuit, and the positive pole of voltage-stabiliser tube Z1 is connected to ground.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 A of bleeder circuit constitutes the reference voltage output terminal of described reference voltage unit 200, by the low pass filter of being 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 multiple constant current led drive circuit with defencive function of the present utility model 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, constitutes the feedback signal input of constant current feedback unit 300; The output of operational amplifier A R1A connects the low pass filter of being made up of resistance R 8 and capacitor C 5, constitutes 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 multiple constant current led drive circuit with defencive function of the present utility model shown in Figure 1, having the constant flow element of controlling the utmost point is power output triode Q1, Q2 and Q3; The described control utmost point is the base stage of power output triode, and power output triode Q1, the Q2 of each constant current branch road and the base stage of Q3 are connected in parallel, and constitutes the input of described multi-channel sampling current-sharing unit 400; The collector electrode of each road power output triode Q1, Q2 or Q3, constitute one tunnel constant current output (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 output triode Q1, Q2, Q3, by described sampling resistor Rs1, Rs2, Rs3 ground connection, the emitter of power output 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, just 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 the electric current that flows through on the LED multi-path electric current string simultaneously 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.In the embodiment shown in fig. 1, reference voltage unit 200 constitutes a linear constant current circuit with operational amplifier A R1A, constant flow element Q1, sampling resistor Rs1, the feedback resistance Rf1 of constant current feedback unit 300, drive for the first paths of LEDs string provides constant current, analogize on all the other each roads.
Though constant flow element Q1, the Q2 that control the utmost point having among the embodiment shown in Figure 1 and Q3 are the power output triodes, the multiple constant current led drive circuit with defencive function of the present utility model equally also can adopt power MOS pipe to form sampling constant current branch road.Under the situation that adopts power MOS pipe, the control utmost point of constant flow element is the grid of power output mos pipe, and the grid of the power output mos pipe of each constant current branch road is connected in parallel, and constitutes the input of described multi-channel sampling current-sharing unit; The drain electrode of each road power output mos pipe constitutes one tunnel constant current output 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 output mos pipe is by described sampling resistor Rs1, Rs2, Rs3 ground connection, the source electrode of power output mos pipe 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, just the inverting input of operational amplifier A R1A (C point among Fig. 1).
In the embodiment of multiple constant current led drive circuit with defencive function of the present utility model shown in Figure 1, each road of multichannel failure detection circuit 500a comprises diagnosis triode Q51, a Q52 or Q53, the base stage of diagnosis triode Q51, Q52 or Q53 connect a base stage current-limiting resistance R31, R32 or R33, constitute described detection input, correspondence is connected to described constant current output F1, F2 or F3; The grounded emitter of each road diagnosis triode Q51, Q52 and Q53; The collector electrode of each road diagnosis triode Q51, Q52 and Q53 is connected to the positive pole of LED respectively through pull-up resistor R51, R52 and R53, the collector electrode of each road diagnosis triode and the tie point of its pull-up resistor constitute described detection output G1, G2 or G3 respectively.In this embodiment, OR circuit is made up of diode D81, D82 and the D83 that negative pole links together; Controllable electronic switch is metal-oxide-semiconductor Q8, and the control of controllable electronic switch is the grid of metal-oxide-semiconductor Q8 very, and the drain electrode of metal-oxide-semiconductor Q8 is connected to the output end of pressure-stabilizing D of reference voltage unit 200, the source ground of metal-oxide-semiconductor Q8.When having a LEDs to open circuit in any paths of LEDs string, then the constant current output F1, the F2 that connect of this paths of LEDs polyphone or the voltage of F3 become 0, the base voltage of corresponding one tunnel diagnosis triode Q51, Q52 or Q53 becomes 0, corresponding diagnosis triode Q51, Q52 or Q53 end, its collector electrode is moved to the high level of LED positive pole on pull-up resistor R51, R52 or the R53, the voltage that just detects output G1, G2 or G3 becomes high level, and the grid that is connected to the metal-oxide-semiconductor Q8 of OR circuit output becomes high level.Therefore, no matter the LED element in which paths of LEDs string opens circuit, all will make controllable electronic switch metal-oxide-semiconductor Q8 conducting.Because the drain electrode of Q8 is connected with the reference voltage point D of reference voltage unit 200, when Q8 is conducting to ground, then the D voltage of ordering also is pulled to ground, and the reference voltage of constant current feedback unit 300 is 0 o'clock, and linear constant current circuit quits work, and the entire circuit current sinking is almost 0.When vehicle body control unit BCM detects on this power line the no consumption electric current, both can judge the LED fault and show that fault was on panel board, therefore can save the alarm signal line of the necessary connection of prior art scheme BCM, not need BCM to reserve extra alarm signal mouth to light fixture.
In the embodiment of multiple constant current led drive circuit with defencive function of the present utility model shown in Figure 1; led drive circuit also comprises LED protected location 700; LED protected location 700 comprises protection control circuit and overvoltage sample circuit; the protection control circuit is made up of resistance R 15, metal-oxide-semiconductor Q7; the grid of metal-oxide-semiconductor Q7 constitutes the sampled signal input E of protection control circuit; the source ground of metal-oxide-semiconductor Q7; the drain electrode of metal-oxide-semiconductor Q7 is connected to the reference voltage output terminal A of reference voltage unit 200 through resistance R 15.The overvoltage sample circuit is the bleeder circuit that resistance R 16 and R21 form, and power source voltage Vcc connects the reference voltage output terminal A of reference voltage unit 200 after resistance R 16 and R21 dividing potential drop.When input voltage Vcc is too high, the voltage of the dividing point E of divider resistance R16, R21 also can raise with input voltage Vcc, when the E point voltage is elevated to a certain degree, for example greater than 4V, be that the grid voltage of metal-oxide-semiconductor Q7 is greater than 4V, then Q7 is conducting to ground, just makes an end of resistance R 15 be connected to ground.For reference voltage unit 200, be equivalent on the divider resistance R4 of reference voltage unit 200 resistance R 15 in parallel, because the resistance of R4 R15 in parallel is less than the resistance of former divider resistance R4, the output reference voltage Vref of the reference voltage output terminal A of reference voltage unit 200 will reduce.Be example with LED11, LED12, LED13 one paths of LEDs string, according to the principle of linear constant current circuit as can be known, flow through the electric current I led=Vref/Rs1 of every paths of LEDs string, therefore, output reference voltage Vref will reduce, the electric current I led that flows through LED on this paths of LEDs string road is corresponding reducing also, and the power consumption on the constant flow element Q1 is corresponding reducing also.Therefore the electric current of constant flow element Q1, Q2, Q3 was avoided constant flow element owing to bore multivoltage under LED protected location 700 can reduce when input voltage is too high, and power consumption is excessive, heat is too much and the risk of damage, had reached the purpose of overvoltage protection.In the embodiment shown in fig. 1, at diode D2 of the lower end of resistance R 21 series connection, be used for metal-oxide-semiconductor Q7 is done temperature-compensating.Because under the high temperature, the grid source electrode conducting voltage of metal-oxide-semiconductor can reduce, reduce to shift to an earlier date conducting for fear of the grid source electrode conducting voltage because of metal-oxide-semiconductor, here the characteristic of having utilized the forward conduction voltage drop VF of diode D2 at high temperature also to reduce, the conducting voltage of offsetting metal-oxide-semiconductor Q7 reduces the influence to the E point voltage.
In the embodiment of multiple constant current led drive circuit with defencive function of the present utility model shown in Figure 1; LED protected location 700 also comprises the overtemperature sample circuit; the overtemperature sample circuit is made up of resistance R 18 and thermistor Rt; thermistor Rt is installed on the LED wiring board PCB1; among Fig. 1 with solid wire frame representation LED wiring board PCB1; the end of thermistor Rt is connected to input voltage Vcc, and the other end of thermistor Rt is connected to the sampled signal input of described LED protected location through resistance R 18.In this embodiment, thermistor Rt adopts negative tempperature coefficient thermistor NTC, by thermistor Rt being mounted on the LED wiring board PCB1, when LED wiring board PCB1 was overheated, the resistance of thermistor Rt reduced with increase in temperature, so, the resistance of Rt+R18 reduces, and the voltage of dividing point E can raise, when voltage is elevated to a certain degree, make metal-oxide-semiconductor Q7 be conducting to ground, R15 is connected to ground.R15 reduces with both total resistances after R4 is in parallel, and the output reference voltage Vref of the reference voltage output terminal A of reference voltage unit 200 reduces.Be example with LED11, LED12, LED13 one paths of LEDs string, according to the principle of linear constant current circuit as can be known, flow through the electric current I led=Vref/Rs1 of every paths of LEDs string, therefore, output reference voltage Vref will reduce, the electric current I led that flows through LED on this paths of LEDs string road is corresponding reducing also, and the power consumption on the constant flow element Q1 is corresponding reducing also.Therefore; by increasing the overtemperature sample circuit; and thermistor Rt is installed on the LED wiring board PCB1; under can reducing, LED protected location 700 flows through the electric current of every paths of LEDs string when the LED wiring board is overheated; thereby reduce LED and use power; reach LED overtemperature prote purpose, prolong LED useful life.This point is for being used for the led drive circuit of LED car light; be vital; because the vehicle that run at high speed at highway night; no matter be that the LED element damages because of transient overvoltage; or cut off the electricity supply when the overvoltage because of existing overvoltage crowbar, all may have a strong impact on traffic safety.The present invention adopts to fall power light-emitting rather than stop luminous mode and realizes overvoltage protection and overtemperature prote, can provide continual illumination when realizing the LED defencive function, thereby guarantees travel safety.
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. multiple constant current led drive circuit with defencive function; 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 at least 1 LED coupled in series element respectively, it is characterized in that:
Described led drive circuit comprises reference voltage unit, constant current feedback unit, multi-channel sampling current-sharing unit and LED string fail safe 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 that has constant flow element and a sampling resistor that is connected in series with constant flow element of controlling the utmost point, and the constant current output 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 constitutes 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, constitutes closed loop constant current control loop;
Described LED string fail safe unit comprises multichannel failure detection circuit and controllable electronic switch; Each paths of LEDs string corresponding to the LED multi-path light emitting module, described multichannel failure detection circuit arranges one and detects input and a detection output, each of multichannel failure detection circuit detects input, and correspondence is connected to the constant current output that connects with this paths of LEDs polyphone; Each of multichannel failure detection circuit detects output, is connected to the control utmost point of described controllable electronic switch by OR circuit, and described controllable electronic switch is formed controlled grounded circuit between the output end of pressure-stabilizing of described voltage stabilizing circuit and earth terminal.
2. the multiple constant current led drive circuit with defencive function according to claim 1 is characterized in that described reference voltage unit comprises the voltage stabilizing circuit that current-limiting resistance R2 and voltage-stabiliser tube Z1 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 constitutes the reference voltage output terminal of described reference voltage unit, by the low pass filter of being formed by resistance R 5 and capacitor C 3, be connected to the reference voltage input terminal of described constant current feedback unit.
3. the multiple constant current led drive circuit with defencive function 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, constitutes the feedback signal input of described constant current feedback unit; The output of described operational amplifier A R1A connects the low pass filter of being made up of resistance R 8 and capacitor C 5, constitutes the output of constant current feedback unit, is connected to the input of described multi-channel sampling current-sharing unit.
4. the multiple constant current led drive circuit with defencive function according to claim 1 is characterized in that the described constant flow element of controlling the utmost point that has is the power output triode; The described control utmost point is the base stage of power output triode, and the base stage of the power output triode of each constant current branch road is connected in parallel, and constitutes the input of described multi-channel sampling current-sharing unit; The collector electrode of each road power output triode constitutes one tunnel constant current output 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 output triode is by described sampling resistor ground connection, being connected in series a little of the emitter of power output 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. the multiple constant current led drive circuit with defencive function according to claim 1 is characterized in that the described constant flow element of controlling the utmost point that has is power output mos pipe; The described control utmost point is the grid of power output mos pipe, and the grid of the power output mos pipe of each constant current branch road is connected in parallel, and constitutes the input of described multi-channel sampling current-sharing unit; The drain electrode of each road power output mos pipe constitutes one tunnel constant current output 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 output mos pipe is by described sampling resistor ground connection, being connected in series a little of the source electrode of power output mos pipe and sampling resistor, link together by a feedback resistance respectively, be connected to the feedback signal input of described constant current feedback unit.
6. the multiple constant current led drive circuit with defencive function according to claim 1, each road that it is characterized in that described multichannel failure detection circuit comprises a diagnosis triode, the base stage base stage current-limiting resistance of connecting of diagnosis triode, constitute described detection input, correspondence is connected to described constant current output; The grounded emitter of diagnosis triode, the collector electrode of diagnosis triode is connected to the positive pole of LED through pull-up resistor, and the tie point of collector electrode and pull-up resistor constitutes described detection output.
7. according to the described multiple constant current led drive circuit with defencive function of the arbitrary claim of claim 1 to 6, it is characterized in that led drive circuit also comprises the LED protected location, described LED protected location comprises protection control circuit and overvoltage sample circuit, described protection control circuit is made up of resistance R 15, metal-oxide-semiconductor Q7, the grid of metal-oxide-semiconductor Q7 constitutes the sampled signal input of protection control circuit, the source ground of metal-oxide-semiconductor Q7, the drain electrode of metal-oxide-semiconductor Q7 is connected to the reference voltage output terminal of reference voltage unit through resistance R 15; Described overvoltage sample circuit is the bleeder circuit that resistance R 16 and R21 form, and input voltage Vcc is connected to described sampled signal input after resistance R 16 and R21 dividing potential drop.
8. the multiple constant current led drive circuit with defencive function according to claim 7; it is characterized in that the LED protected location also comprises the overtemperature sample circuit; described overtemperature sample circuit is made up of resistance R 18 and thermistor Rt; described thermistor Rt is installed on the LED wiring board; the end of thermistor Rt is connected to input voltage Vcc, and the other end of thermistor Rt is connected to the sampled signal input of described LED protected location through resistance R 18.
9. one kind is used for the described circuit board structure with multiple constant current led drive circuit of defencive function of claim 8; it is characterized in that described wiring board comprises LED wiring board PCB1 and control circuit board PCB2, described thermistor Rt is mounted on the LED wiring board PCB1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201220565743XU CN203057594U (en) | 2012-10-31 | 2012-10-31 | Multipath constant current LED drive circuit with protection function and circuit board structure thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201220565743XU CN203057594U (en) | 2012-10-31 | 2012-10-31 | Multipath constant current LED drive circuit with protection function and circuit board structure thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203057594U true CN203057594U (en) | 2013-07-10 |
Family
ID=48740506
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201220565743XU Expired - Lifetime CN203057594U (en) | 2012-10-31 | 2012-10-31 | Multipath constant current LED drive circuit with protection function and circuit board structure thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203057594U (en) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102917508A (en) * | 2012-10-31 | 2013-02-06 | 上海小糸车灯有限公司 | Multi-path constant current LED drive circuit with protection function and circuit board structure thereof |
| CN104582122A (en) * | 2013-10-29 | 2015-04-29 | 常州星宇车灯股份有限公司 | Overvoltage-controlled LED constant current circuit |
| CN105263248A (en) * | 2015-10-29 | 2016-01-20 | 奇瑞汽车股份有限公司 | Fault feedback protection circuit of LED daytime running lamp for vehicles |
| CN106291010A (en) * | 2016-08-11 | 2017-01-04 | 河北白晶环境科技有限公司 | High-precision multi-channel controllable constant current source |
| CN106322321A (en) * | 2016-11-03 | 2017-01-11 | 中山市荣亮照明有限公司 | LED illumination down lamp with protection constant current drive |
| CN107318197A (en) * | 2017-08-17 | 2017-11-03 | 无锡市益明光电有限公司 | A kind of LED multi-path current balance circuit |
| CN107642754A (en) * | 2017-10-13 | 2018-01-30 | 上海小糸车灯有限公司 | Automobile-used front fog lamp and daytime running lamps multiplexing light fixture and construction method |
| WO2018192081A1 (en) * | 2017-04-19 | 2018-10-25 | 深圳市大疆创新科技有限公司 | Voltage stabilizing circuit and power supply circuit and remote control having same |
| WO2020010857A1 (en) * | 2018-07-12 | 2020-01-16 | 深圳光峰科技股份有限公司 | Human sensing system for electronic device and electronic device |
| CN111565496A (en) * | 2019-11-07 | 2020-08-21 | 华域视觉科技(上海)有限公司 | LED current-sharing control circuit and system |
| CN115767836A (en) * | 2023-01-09 | 2023-03-07 | 深圳北极之光科技有限公司 | Lamp circuit |
-
2012
- 2012-10-31 CN CN201220565743XU patent/CN203057594U/en not_active Expired - Lifetime
Cited By (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102917508B (en) * | 2012-10-31 | 2014-12-10 | 上海小糸车灯有限公司 | Multi-path constant current LED drive circuit with protection function and circuit board structure thereof |
| CN102917508A (en) * | 2012-10-31 | 2013-02-06 | 上海小糸车灯有限公司 | Multi-path constant current LED drive circuit with protection function and circuit board structure thereof |
| CN104582122A (en) * | 2013-10-29 | 2015-04-29 | 常州星宇车灯股份有限公司 | Overvoltage-controlled LED constant current circuit |
| CN104582122B (en) * | 2013-10-29 | 2018-03-13 | 常州星宇车灯股份有限公司 | The LED constant current circuit of overvoltage control |
| CN105263248A (en) * | 2015-10-29 | 2016-01-20 | 奇瑞汽车股份有限公司 | Fault feedback protection circuit of LED daytime running lamp for vehicles |
| CN105263248B (en) * | 2015-10-29 | 2017-08-04 | 奇瑞汽车股份有限公司 | A kind of failure feedback protection circuit of automobile-used LED daytime running lamps |
| CN106291010A (en) * | 2016-08-11 | 2017-01-04 | 河北白晶环境科技有限公司 | High-precision multi-channel controllable constant current source |
| CN106322321B (en) * | 2016-11-03 | 2019-10-18 | 诸暨市霞伟花木场 | LED illumination downlight with protection constant current driving |
| CN106322321A (en) * | 2016-11-03 | 2017-01-11 | 中山市荣亮照明有限公司 | LED illumination down lamp with protection constant current drive |
| WO2018192081A1 (en) * | 2017-04-19 | 2018-10-25 | 深圳市大疆创新科技有限公司 | Voltage stabilizing circuit and power supply circuit and remote control having same |
| CN107318197A (en) * | 2017-08-17 | 2017-11-03 | 无锡市益明光电有限公司 | A kind of LED multi-path current balance circuit |
| CN107642754A (en) * | 2017-10-13 | 2018-01-30 | 上海小糸车灯有限公司 | Automobile-used front fog lamp and daytime running lamps multiplexing light fixture and construction method |
| CN107642754B (en) * | 2017-10-13 | 2023-12-05 | 华域视觉科技(上海)有限公司 | Multiplexing lamp for front fog lamp and daytime running lamp of vehicle and construction method |
| WO2020010857A1 (en) * | 2018-07-12 | 2020-01-16 | 深圳光峰科技股份有限公司 | Human sensing system for electronic device and electronic device |
| CN111565496A (en) * | 2019-11-07 | 2020-08-21 | 华域视觉科技(上海)有限公司 | LED current-sharing control circuit and system |
| CN111565496B (en) * | 2019-11-07 | 2022-07-05 | 华域视觉科技(上海)有限公司 | LED current-sharing control circuit and system |
| CN115767836A (en) * | 2023-01-09 | 2023-03-07 | 深圳北极之光科技有限公司 | Lamp circuit |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| 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 | |
| CN101355842B (en) | Lighting control for vehicle lighting device | |
| US10849198B2 (en) | Light emitting diode thermal foldback control device and method | |
| CN102905443A (en) | Linear constant-current and current-sharing LED drive circuit and circuit board structure thereof | |
| CN201220626Y (en) | PWM type lighteness adjustable module group for LED automobile tail lamp | |
| CN203136298U (en) | PWM control module of LED stop lamps with fault diagnosis function | |
| JP3140830U (en) | Circuit device for vehicle lighting equipment | |
| JPWO2016104282A1 (en) | Light source lighting circuit, turn signal lamp | |
| CN101401486A (en) | Temperature controlled LED array | |
| CN202857100U (en) | Linear constant current current sharing LED driving circuit and circuit board structure thereof | |
| CN103137080B (en) | Light-emitting dioxide (LED) backlight drive circuit, liquid crystal display device and driving method | |
| CN101712297A (en) | Vehicular lamp | |
| JP2014241202A (en) | Led lighting device for vehicular lamp fitting | |
| JP2014151717A (en) | Overvoltage protection device for vehicular lighting fixture | |
| CN202728072U (en) | LED (Light-emitting Diode) tail lamp with CAN (Controller Area Network) transceiver | |
| JP2009051276A (en) | Control circuit of vehicular lightning device, and vehicular lightning device | |
| KR101342057B1 (en) | Circuit for Protecting Light-Emitting Diode Driving Module for vehicle | |
| EP2147824B1 (en) | Circuit for controlling the presence of a trailer connected to a towing truck, via the control of the electric current flow in the rear led lamps of the trailer | |
| CN201047522Y (en) | Circuit structure of LED illuminating device | |
| CN104582122A (en) | Overvoltage-controlled LED constant current circuit | |
| CN107512216A (en) | The control circuit of automobile daytime driving lamp and position lamp integrated lamp | |
| CN203036429U (en) | Light-emitting diode (LED) light for separation equipment | |
| CN212183767U (en) | Novel LED sectional lighting illumination driving device | |
| KR101185832B1 (en) | Alarm circuit using of redish particle of white led |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CP01 | Change in the name or title of a patent holder | ||
| CP01 | Change in the name or title of a patent holder |
Address after: 201800 Yecheng Road, Jiading District, Jiading District, Shanghai Patentee after: HUAYU VISION TECHNOLOGY (SHANGHAI) Co.,Ltd. Address before: 201800 Yecheng Road, Jiading District, Jiading District, Shanghai Patentee before: SHANGHAI KOITO AUTOMOTIVE LAMP Co.,Ltd. |
|
| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term |
Granted publication date: 20130710 |