WO2018024220A1 - Led驱动电路及led灯管 - Google Patents

Led驱动电路及led灯管 Download PDF

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Publication number
WO2018024220A1
WO2018024220A1 PCT/CN2017/095673 CN2017095673W WO2018024220A1 WO 2018024220 A1 WO2018024220 A1 WO 2018024220A1 CN 2017095673 W CN2017095673 W CN 2017095673W WO 2018024220 A1 WO2018024220 A1 WO 2018024220A1
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WO
WIPO (PCT)
Prior art keywords
led
circuit
resistor
load impedance
threshold
Prior art date
Application number
PCT/CN2017/095673
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English (en)
French (fr)
Inventor
文威
Original Assignee
欧普照明股份有限公司
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
Priority claimed from CN201620828330.4U external-priority patent/CN206196082U/zh
Priority claimed from CN201610626520.2A external-priority patent/CN106102253B/zh
Application filed by 欧普照明股份有限公司 filed Critical 欧普照明股份有限公司
Priority to EP17836402.2A priority Critical patent/EP3481159B1/en
Publication of WO2018024220A1 publication Critical patent/WO2018024220A1/zh
Priority to US16/266,014 priority patent/US10645775B2/en

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    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/30—Driver circuits
    • H05B45/357—Driver circuits specially adapted for retrofit LED light sources
    • H05B45/3578—Emulating the electrical or functional characteristics of discharge lamps
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/30—Driver circuits
    • H05B45/37—Converter circuits
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/50—Circuit arrangements for operating light-emitting diodes [LED] responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/50—Circuit arrangements for operating light-emitting diodes [LED] responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits
    • H05B45/58—Circuit arrangements for operating light-emitting diodes [LED] responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits involving end of life detection of LEDs
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/30—Driver circuits
    • H05B45/37—Converter circuits
    • H05B45/3725—Switched mode power supply [SMPS]
    • H05B45/39—Circuits containing inverter bridges
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
    • Y02B20/30—Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Definitions

  • the present invention relates to the field of lighting technologies, and in particular, to an LED driving circuit and an LED tube.
  • AC is the mains input. After passing through the electronic ballast, it outputs high-frequency AC voltage and AC current to the LED tube.
  • the filament analog circuit is used to simulate the impedance of the traditional fluorescent filament, and the rectifier bridge. It is used to convert high-frequency AC voltage and AC current into DC voltage and DC current, and then convert it into a suitable voltage and current to illuminate the LED particles through a power conversion circuit.
  • FIG. 2 is a schematic circuit diagram of a conventional LED driving circuit, wherein the switch S1, the switch S2, the DC blocking capacitor Cb, the resonant inductor Lr, and the resonant capacitor Cr belong to an internal circuit of the electronic ballast, and the switches S1 and S2 form a half bridge circuit, which is high.
  • Frequency conversion high voltage bus voltage DC blocking capacitor Cb removes the DC part of the high frequency voltage and converts it into an AC high frequency voltage signal
  • the resonant inductor Lr and the resonant capacitor Cr form a resonant cavity for resonant lighting when the fluorescent lamp is connected, and the resonant inductor Lr is After the stable work, the flow restriction function.
  • the LED tube is connected to the electronic ballast through terminals 1, 2, 3 and 4, and passes through the filament analog circuit and enters the diode D1, D2, D3.
  • the rectifier bridge composed of D4 the high-frequency AC signal from the ballast is converted into a DC signal through the rectifier bridge, and output to the LED light source through the power conversion circuit.
  • the present invention provides an LED drive circuit and an LED lamp to overcome the above problems or at least partially solve the above problems.
  • an LED driving circuit includes: a feedback control circuit and a load impedance increasing circuit, wherein the feedback control circuit collects an operating current of the LED and compares it with a predetermined threshold when When the operating current of the LED is greater than or equal to the threshold, driving the load impedance increasing circuit to operate, when the operating current of the LED is less than the threshold, the load impedance increasing circuit does not work; and the load impedance increasing circuit is working , increasing the load equivalent impedance of the LED driving circuit.
  • the LED driving circuit further includes: a rectifier bridge, wherein the load impedance increasing circuit is disposed between the rectifier bridge and the LED.
  • the load impedance increasing circuit includes: a load impedance increasing component and a switching component connected in parallel with the load impedance increasing component, wherein the load impedance increasing component is bypassed when the switching component is turned on, the switch When the component is disconnected, the load impedance increasing component is connected to the LED driving circuit to increase the load equivalent impedance of the LED driving circuit.
  • the switching element comprises: a power transistor, a field effect transistor or a relay.
  • the threshold is a threshold voltage
  • the feedback control circuit includes: a current detecting unit, a threshold comparing unit, and a driving unit, wherein the current detecting unit collects an operating current of the LED to convert it into a comparison voltage, and inputs To the threshold comparison unit, the threshold comparison unit compares the comparison voltage with the threshold voltage, and when the comparison voltage is greater than or equal to the threshold voltage, controls the driving unit to start operating to drive the load The impedance increasing circuit operates. When the comparison voltage is less than the threshold voltage, the driving unit does not operate, and the load impedance increasing circuit does not operate.
  • the current detecting unit comprises: a sampling resistor, a transformer or a Hall sensor.
  • the current detecting unit comprises: a sampling resistor, the sampling resistor is connected in series with the LED, and an operating current of the LED flows through the sampling resistor to generate the comparison voltage.
  • the threshold comparison unit includes: a comparator connected to a positive terminal of the comparator, the threshold voltage is connected to a negative end of the comparator, and an output of the comparator is connected To the drive unit, the output of the comparator is also connected to the positive terminal of the comparator.
  • the threshold comparison unit further includes: a first resistor, a second resistor, a third resistor, and a fourth resistor, wherein the sampling resistor is connected to a positive terminal of the comparator through the first resistor, a threshold voltage is coupled to a negative terminal of the comparator through the second resistor, an output of the comparator being coupled to a positive terminal of the comparator through the third resistor, an output of the comparator passing through A fourth resistor is coupled to the drive unit.
  • the driving unit includes: a switching transistor, a current limiting resistor, a freewheeling diode, a base of the switching transistor is connected to an output end of the threshold comparing unit, and an emitter of the switching transistor is grounded, A collector of the switching transistor is coupled to the freewheeling diode through the current limiting resistor, the freewheeling diode being in anti-parallel with a switching element of the load impedance increasing circuit.
  • the LED driving circuit further includes: a power conversion circuit;
  • the load impedance increasing component is an impedance inductor,
  • the switching component is a relay, and the relay includes: a driving winding and a relay switch, and one end of the driving winding Connected to the collector of the switching transistor by the current limiting resistor, the other end of the driving winding is connected to a power supply, the driving winding is connected in anti-parallel with the freewheeling diode, the relay switch and the impedance
  • the inductors are connected in parallel, and the two ends of the impedance inductor are respectively connected to the rectifier bridge and the power conversion circuit.
  • the LED driving circuit further includes: a power conversion circuit; the driving unit includes: an optocoupler module, a first voltage dividing resistor, a second voltage dividing resistor, a Zener diode, and an input end of the optocoupler module is connected Up to an output end of the threshold comparison unit, an output end of the optocoupler module is connected to the load impedance increasing circuit, and a bus bar of the rectifier bridge is connected through the first voltage dividing resistor and the second voltage dividing resistor To the switching element of the load impedance increasing circuit, both ends of the Zener diode are respectively connected to both ends of the switching element.
  • the driving unit includes: an optocoupler module, a first voltage dividing resistor, a second voltage dividing resistor, a Zener diode, and an input end of the optocoupler module is connected Up to an output end of the threshold comparison unit, an output end of the optocoupler module is connected to the load impedance increasing circuit, and a bus bar of the rectifier bridge is connected
  • the load impedance increasing component is an impedance inductor
  • the switching component is a field An effect transistor
  • a bus bar of the rectifier bridge is connected to a gate of the field effect transistor through the first voltage dividing resistor and the second voltage dividing resistor, and a gate of the field effect transistor is simultaneously connected to the light
  • An output end of the coupling module a gate and a source of the FET are respectively connected to two ends of the Zener diode, and two ends of the impedance inductor are respectively connected to a source and a drain of the FET
  • the one end of the impedance inductance connected to the source of the FET is simultaneously connected to the rectifier bridge, and the end of the impedance inductance connected to the drain of the FET is simultaneously connected to the power conversion circuit.
  • an LED lamp comprising any one of the above LED driving circuits and at least one LED connected to the LED driving circuit, wherein the LED driving circuit is configured to drive at least one LED to operate after power-on.
  • the LED driving circuit provided by the embodiment of the invention is suitable for the LED lamp tube application compatible with the electronic ballast, especially for the constant power ballast or the magnetic ring self-excited driving ballast, which can reduce the output power of the ballast and make the LED
  • the lamp can work at rated power to avoid damage or premature aging of the LED tube due to over-power usage.
  • 1 is a schematic structural view of a conventional LED driving circuit
  • FIG. 2 is a schematic circuit diagram of a conventional LED driving circuit
  • FIG. 3 is a schematic structural diagram of an LED driving circuit according to an embodiment of the present invention.
  • FIG. 4 is a block diagram showing the structure of an LED driving circuit in accordance with a preferred embodiment of the present invention.
  • FIG. 5 is a schematic diagram showing the circuit structure of an LED driving circuit according to a preferred embodiment of the present invention.
  • FIG. 6 is a circuit diagram showing the structure of an LED driving circuit in accordance with another preferred embodiment of the present invention.
  • the LED driving circuit provided by the embodiment of the invention can directly work with the module of the existing LED driving circuit.
  • the LED driving circuit according to the embodiment of the present invention includes a feedback control circuit 13 and a load impedance increasing circuit 14, which can directly cooperate with the filament analog circuit 10, the rectifier bridge 11, and the power conversion circuit 12, and the entire LED driver
  • the circuit is used to drive at least one LED illumination operation after power up, and FIG. 3 shows only one LED.
  • the load impedance increasing circuit 14 may be disposed between the rectifier bridge 11 and the LEDs described above.
  • the feedback control circuit 13 collects the operating current of the LED and compares it with a predetermined threshold.
  • the driving load impedance increasing circuit 14 operates when the operating current of the LED is less than the threshold.
  • the load impedance increasing circuit 14 does not work;
  • the load impedance increasing circuit 14 When the load impedance increasing circuit 14 operates, the load equivalent impedance of the LED driving device is increased.
  • the LED driving circuit provided in this embodiment can improve the load equivalent impedance of the entire LED driving circuit when the LED power is too high, thereby reducing the output current of the electronic ballast and achieving the purpose of reducing the output power.
  • the LED driving circuit provided by the embodiment is suitable for the LED lamp tube application compatible with the electronic ballast, especially for the constant power ballast or the magnetic ring self-excited driving ballast, which can reduce the ballast output power and make the LED lamp tube Can work at rated power, Avoid damage or premature aging of LED tubes due to excessive power usage.
  • the feedback control circuit 13 can be implemented by the following architecture.
  • the feedback control circuit 13 may include a current detecting unit 131, a threshold comparing unit 132, and a driving unit 133.
  • the current detecting unit 131 collects an operating current of the LED to convert it into a comparison voltage, and inputs it to the threshold comparing unit 132.
  • the threshold comparison unit 132 compares the comparison voltage with the threshold voltage. When the comparison voltage is greater than or equal to the threshold voltage, the control driving unit 133 starts to operate to drive the load impedance increasing circuit 14 to operate. When the comparison voltage is less than the threshold voltage, the driving unit 133 does not. At work, the load impedance increase circuit 14 does not operate.
  • the preferred embodiment provides a solution for preferably implementing the feedback control circuit 13.
  • the functions of the feedback control circuit 13 can be fully implemented based on the current detecting unit 131, the threshold comparing unit 132, and the driving unit 133, and the architecture is simple and the control logic is clear.
  • a method of converting current into voltage for comparison is adopted, which can greatly simplify the circuit structure and lower cost.
  • the above threshold is the voltage threshold.
  • the current detecting unit 131 can be directly realized based on the sampling resistor, the transformer or the Hall sensor, that is, the function of collecting current can be realized by using the sampling resistor, the transformer, and the Hall sensor.
  • the load impedance increasing circuit 14 can be implemented by the load impedance increasing element 141 and the switching element 142 in parallel with the load impedance increasing element 141.
  • the load impedance increasing element 141 is bypassed.
  • the load equivalent impedance of the LED driving circuit does not change; when the switching element 142 is turned off, the load impedance increasing component 141 is connected to the LED driving circuit to increase the load equivalent impedance of the LED driving circuit.
  • the load impedance increasing circuit 14 may be disposed between the rectifier bridge 11 and the power conversion circuit 12, the load impedance increasing element 141 may be implemented by an inductance in series with the rectifier bridge 11 and the power conversion circuit 12, and the switching element 142 It can be realized by a power transistor, a field effect transistor or a relay.
  • the switching element 142 is controlled by the LED current, and is connected to the current detecting unit 131 in the LED circuit.
  • the comparison result is input to the driving unit 133 by threshold comparison, and the driving unit 133 controls the turning on and off of the switching element 142.
  • the current detecting unit 131 can feed back the magnitude of the current of the LED, and the current is compared with the set threshold.
  • the driving unit 133 turns on the switching element 142, and the load impedance increasing element 141 is Short circuit, the working state is unchanged; when the current flowing through the LED is larger than the set threshold, the driving unit 133 disconnects the switch K, and the load impedance increases the component 141 is connected between the rectifier bridge 11 and the power conversion circuit 12 to increase the load equivalent impedance of the LED drive circuit.
  • the LED operating current and the predetermined threshold magnitude are compared, the current can be replaced by a voltage for comparison, and the predetermined threshold is set to the threshold voltage.
  • the load impedance increasing component 141 can be realized by an inductor because the electronic ballast outputs a high frequency voltage and a high frequency current, and the inductor exhibits a certain impedance value under a high frequency current.
  • the inductor When the inductor is connected to the circuit, the impedance value The relationship with the subsequent power conversion circuit is formed in series, so that the load equivalent impedance can be improved, the electronic ballast can reduce the output current, and the output power can be reduced.
  • the inductance and the subsequent power conversion circuit are connected in series, and the load impedance characteristics can also be changed.
  • the total harmonic distortion of the input current can be reduced.
  • a circuit structure as shown in FIG. 5 can be established.
  • the rectifier bridge 11 is composed of diodes D1, D2, D3, and D4.
  • the load impedance increasing circuit 14 is disposed between the rectifier bridge 11 and the power conversion circuit 12, and includes an inductor L, a relay K1, and a relay K1. In the case of excitation, it is often closed.
  • the current detecting unit 131 is realized by the sampling resistor Rs, and the current sampling resistor Rs is serially connected into the LED circuit, and the LED current flows through the sampling resistor Rs to generate a corresponding voltage, that is, a comparison voltage.
  • the threshold comparison unit 132 is implemented based on the comparator U1.
  • the first resistor R1, the second resistor R2, the third resistor Rfb, and the fourth resistor Rd may be added, and the comparison voltage is fed back through the first resistor R1.
  • the positive terminal of the comparator U1, the threshold voltage Vref is connected to the negative terminal of the comparator U1 via the second resistor R2; the output of the comparator U1 is fed back to the positive terminal through the third resistor Rfb on the one hand, and is driven by the fourth resistor Rd on the other hand.
  • the driving unit 133 includes a switching transistor Q1.
  • the collector of the switching transistor Q1 is connected to the relay K1 driving winding current limiting resistor through the current limiting resistor R3, R3 is used to limit the current flowing through the driving winding of the relay K1, and the other end of the driving winding is connected to the power supply Vcc, and the driving winding is reversely connected in parallel.
  • Diode Dr is used to provide a freewheeling circuit for the drive winding when the switching transistor Q1 is turned off.
  • the relay K1 Since the relay K1 is normally closed when there is no excitation, the relay K1 remains closed after the circuit is powered on, the inductance L is short-circuited, and the circuit works normally. At this time, a current flows into the LED and is detected by the sampling resistor Rs. If the current flowing into the LED is smaller than the set threshold, the negative terminal of the comparator U1 is larger than the positive terminal, the comparator U1 outputs a low level, and the switching transistor Q1 remains turned off.
  • the drive winding of relay K has no excitation current flowing, relay K1 remains closed; if the current flowing into the LED is larger than the set threshold, the negative terminal of comparator U1 is smaller than the positive terminal, comparator U1 outputs a high level, and the switching transistor Q1 When turned on, the power supply Vcc supplies current into the drive winding of the relay K1, so that the relay K1 is disconnected, and the inductor L is connected to the circuit, thereby reducing the output power of the electronic ballast and reducing the current flowing into the LED.
  • the third resistor Rfb is used for positive feedback.
  • the comparator U1 When the comparator U1 outputs a high level, it is fed back to the positive terminal input through the third resistor Rfb, even if the comparison voltage that is fed back through the sampling resistor Rs is reduced due to the decrease in the LED current, due to the third resistor Rfb
  • the feedback makes the positive terminal of comparator U1 larger than the negative terminal, and comparator U1 maintains a high level output.
  • a circuit structure as shown in FIG. 6 can also be established.
  • the current detecting unit 131 and the threshold comparing unit 132 are identical in structure to the current detecting unit 131 and the threshold comparing unit 132 in the circuit shown in FIG.
  • the load impedance increasing circuit 14 includes an inductor L and a field effect transistor K2.
  • the inductor L is connected in parallel with the field effect transistor K2.
  • the gate of the field effect transistor K2 drives the bus bar from the rectifier bridge 11, passes through the first voltage dividing resistor RA and the second branch.
  • the voltage resistor RB is divided into voltages, and the gate and source of the FET K2 are connected to the Zener diode Dz for limiting the driving voltage.
  • the LED current is detected by the sampling resistor Rs and fed back to the positive terminal of the comparator U1.
  • the threshold voltage Vref is connected to the negative terminal of the comparator U1 via the second resistor R2, and the output terminal of the U1 is fed back to the positive terminal through the third resistor Rfb.
  • the fourth resistor Rd is connected to the optocoupler module U2, and the optocoupler module U2 is used to provide a driving off signal to control the FET K2 to be turned on or off.
  • the bus voltage of the rectifier bridge is supplied to the FET K2 through the first voltage dividing resistor RA and the second voltage dividing resistor RB, so that the FET K2 is saturated and turned on, and the current flowing into the LED is not large.
  • the comparison voltage fed back through the sampling resistor Rs is smaller than the voltage threshold Vref, the comparator U1 outputs a low level, no driving current flows through the optocoupler module U2, the optocoupler module U2 remains off, and the switch K remains closed and turned on.
  • the circuit inductance L does not affect the original work; when the output power of the electronic ballast is too large, the current flowing into the LED becomes larger, exceeding the set threshold, the positive terminal of the comparator U1 is larger than the negative terminal, and the output of the comparator U1 is high.
  • the level-driven optocoupler module U2 the conduction of the optocoupler module U2 causes the gate voltage of the field effect transistor K2 to be pulled low, the field effect transistor K2 to be disconnected, and the inductor L is stringed into the circuit, thereby reducing the output power of the electronic ballast.
  • an LED lamp comprising the above An LED driving circuit and at least one LED connected to the LED driving circuit, wherein the LED driving circuit is configured to drive the at least one LED to emit light after power-on.
  • Embodiments of the present invention provide an LED driving circuit suitable for LED tube applications compatible with electronic ballasts, particularly for constant power ballasts or magnetic ring self-excited driving ballasts, which can reduce ballasts
  • the output power allows the LED tube to operate at rated power, avoiding LED damage or premature aging due to over-power usage, and further improving input current harmonic distortion for electronic ballasts that use passive power factor correction.
  • modules in the devices of the embodiments can be adaptively changed and placed in one or more devices different from the embodiment.
  • the modules or units or components of the embodiments may be combined into one module or unit or component, and further they may be divided into a plurality of sub-modules or sub-units or sub-components.
  • any combination of the features disclosed in the specification, including the accompanying claims, the abstract and the drawings, and any methods so disclosed, or All processes or units of the device are combined.
  • Each feature disclosed in this specification (including the accompanying claims, the abstract and the drawings) may be replaced by alternative features that provide the same, equivalent or similar purpose.
  • the various component embodiments of the present invention may be implemented in hardware, or in a software module running on one or more processors, or in a combination thereof.
  • a microprocessor or digital signal processor may be used in practice to implement some or all of the functionality of some or all of the components of the LED driver circuit in accordance with embodiments of the present invention.
  • the invention can also be implemented as a device or device program (e.g., a computer program and a computer program product) for performing some or all of the methods described herein.
  • a program implementing the invention may be stored on a computer readable medium or may be in the form of one or more signals. Such signals may be downloaded from an Internet website, provided on a carrier signal, or provided in any other form.

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Abstract

一种LED驱动电路及LED灯管，该LED驱动电路包括：反馈控制电路（13）和负载阻抗增加电路（14），其中，反馈控制电路（13）采集LED的工作电流，并与预定的阈值进行比较，当LED的工作电流大于等于阈值时，驱动负载阻抗增加电路（14）工作，当LED的工作电流小于阈值时，负载阻抗增加电路（14）不工作；负载阻抗增加电路（14）工作时，增加LED驱动电路的负载等效阻抗。该LED驱动电路能降低电子镇流器输出功率，使LED灯管工作在设计功率以内，保证LED灯管的正常使用以及产品寿命。

Description

LED驱动电路及LED灯管 技术领域
本发明涉及照明技术领域，特别是涉及一种LED驱动电路及LED灯管。
背景技术
LED的高光效、长寿命以及不含汞的特点，使得采用LED灯管替代传统荧光灯灯管逐渐成为一种趋势。替代应用有两种主要的方式，一种是完全移除原有的荧光灯灯管和镇流器，直接输入市电到LED灯管，但是这种方式需要修改灯具内部接线，因此产生额外的人工费用；另外一种是只替换灯管，安装的LED灯管需要兼容原有的镇流器工作，这种替换非常简单方便，用户可以自己操作而无需聘请专业人员，因此省去相关的人工费用。
在荧光灯镇流器中，电子镇流器有相当大的比例，因而替代荧光灯灯管的一大挑战在于兼容电子镇流器工作。电子镇流器有不同的拓扑结构，而且由于所使用的LED灯管功率往往远低于荧光灯灯管功率，这使得电子镇流器搭配LED灯管工作会有许多困难，目前比较主流的LED驱动电路架构如图1所示。
在图1中，AC为市电输入，经过电子镇流器后，输出高频交流电压和交流电流到LED灯管，在LED灯管内部，灯丝模拟电路用于模拟传统荧光灯灯丝阻抗，整流桥用于把高频交流电压和交流电流转换为直流电压和直流电流，再经过功率变换电路转化为合适的电压电流点亮LED颗粒。
图2是现有LED驱动电路的电路结构示意图，其中开关S1、开关S2、隔直流电容Cb、谐振电感Lr以及谐振电容Cr属于电子镇流器内部电路，开关S1和S2组成半桥电路，高频变换高压母线电压；隔直流电容Cb去除高频电压的直流部分，转换为交流高频电压信号；谐振电感Lr和谐振电容Cr组成谐振腔，用于在接荧光灯时谐振点灯，谐振电感Lr在稳定工作后起限流作用。LED灯管通过端子1、2、3和4连接到电子镇流器，经过灯丝模拟电路之后进入由二极管D1、D2、D3 和D4组成的整流桥，来自镇流器的高频交流信号经过整流桥转化为直流信号，经过功率变换电路输出到LED光源。
现有的LED灯管在连接恒功率电子镇流器或者磁环自激驱动的电子镇流器时，由于电子镇流器保持输出对应荧光灯使用的功率，这往往比LED灯管功率要大很多，过高的功率会使LED灯管触发保护、过热或者过早寿终，影响LED灯管的使用，如果灯管提供对应的内置保护，则会使得LED灯管不兼容该类型电子镇流器，这也会影响产品的销售。
发明内容
鉴于上述问题，提出了本发明提供了一种LED驱动电路及LED灯管以克服上述问题或者至少部分地解决上述问题。
根据本发明的一个方面，提供了一种LED驱动电路，包括：反馈控制电路、负载阻抗增加电路，其中，所述反馈控制电路采集LED的工作电流，并与预定的阈值进行比较，当所述LED的工作电流大于等于所述阈值时，驱动所述负载阻抗增加电路工作，当所述LED的工作电流小于所述阈值时，所述负载阻抗增加电路不工作；所述负载阻抗增加电路工作时，增加所述LED驱动电路的负载等效阻抗。
可选的，上述LED驱动电路还包括：整流桥，所述负载阻抗增加电路设置在所述整流桥和所述LED之间。
可选的，所述负载阻抗增加电路包括：负载阻抗增加元件和与所述负载阻抗增加元件并联的开关元件，所述开关元件导通时，所述负载阻抗增加元件被旁路，所述开关元件断开时，所述负载阻抗增加元件接入所述LED驱动电路，增加所述LED驱动电路的负载等效阻抗。
可选的，所述开关元件包括：功率三极管、场效应管或者继电器。
可选的，所述阈值为阈值电压；所述反馈控制电路包括：电流检测单元、阈值比较单元、驱动单元，所述电流检测单元采集所述LED的工作电流将其转换为比较电压，并输入至所述阈值比较单元，所述阈值比较单元将所述比较电压与所述阈值电压进行比较，当所述比较电压大于等于所述阈值电压时，控制所述驱动单元开始工作以驱动所述负载阻抗增加电路工作，当所述比较电压小于所述阈值电压时，所述驱动单元不工作，所述负载阻抗增加电路不工作。
可选的，所述电流检测单元包括：采样电阻、变压器或者霍尔传感器。
可选的，所述电流检测单元包括：采样电阻，所述采样电阻与所述LED串联，所述LED的工作电流流过所述采样电阻产生所述比较电压。
可选的，所述阈值比较单元包括：比较器，所述采样电阻连接至所述比较器的正端，所述阈值电压接入所述比较器的负端，所述比较器的输出端连接至所述驱动单元，所述比较器的输出端还连接至所述比较器的正端。
可选的，所述阈值比较单元还包括：第一电阻、第二电阻、第三电阻、第四电阻，所述采样电阻通过所述第一电阻连接至所述比较器的正端，所述阈值电压通过所述第二电阻接入所述比较器的负端，所述比较器的输出端通过所述第三电阻连接至所述比较器的正端，所述比较器的输出端通过所述第四电阻连接至所述驱动单元。
可选的，所述驱动单元包括：开关三极管、限流电阻、续流二极管，所述开关三极管的基极连接至所述阈值比较单元的输出端，所述开关三极管的发射极接地，所述开关三极管的集电极通过所述限流电阻连接至所述续流二极管，所述续流二极管与所述负载阻抗增加电路的开关元件反向并联。
可选的，上述LED驱动电路还包括：功率变换电路；所述负载阻抗增加元件为阻抗电感，所述开关元件为继电器，所述继电器包括：驱动绕组和继电开关，所述驱动绕组的一端通过所述限流电阻连接至所述开关三极管的集电极，所述驱动绕组的另一端连接至电源，所述驱动绕组与所述续流二极管反向并联，所述继电开关与所述阻抗电感并联，所述阻抗电感两端分别于所述整流桥和所述功率变换电路连接。
可选的，上述LED驱动电路还包括：功率变换电路；所述驱动单元包括：光耦模块、第一分压电阻、第二分压电阻、稳压二极管，所述光耦模块的输入端连接至所述阈值比较单元的输出端，所述光耦模块的输出端连接至所述负载阻抗增加电路，所述整流桥的母线通过所述第一分压电阻和所述第二分压电阻连接至所述负载阻抗增加电路的开关元件，所述稳压二极管的两端分别与所述开关元件的两端连接。
可选的，所述负载阻抗增加元件为阻抗电感，所述开关元件为场 效应管，所述整流桥的母线通过所述第一分压电阻和所述第二分压电阻连接至所述场效应管的门极，所述场效应管的门极同时连接至所述光耦模块的输出端，所述场效应管的门极和源极分别与所述稳压二极管的两端连接，所述阻抗电感的两端分别与所述场效应管的源极和漏极连接，所述阻抗电感与所述场效应管的源极连接的一端同时与所述整流桥连接，所述阻抗电感与所述场效应管的漏极连接的一端同时与所述功率变换电路连接。
根据本发明的另一个方面，还提供了一种LED灯管，包括上述任一LED驱动电路和与LED驱动电路连接的至少一个LED，LED驱动电路用于在上电后驱动至少一个LED发光工作。
本发明实施例提供的LED驱动电路，适合兼容电子镇流器的LED灯管应用，特别是针对恒功率镇流器或者磁环自激驱动镇流器，能降低镇流器输出功率，使得LED灯管能工作在额定功率，避免因为过功率使用导致LED灯管损坏或者早衰。
上述说明仅是本发明技术方案的概述，为了能够更清楚了解本发明的技术手段，而可依照说明书的内容予以实施，并且为了让本发明的上述和其它目的、特征和优点能够更明显易懂，以下特举本发明的具体实施方式。
根据下文结合附图对本发明具体实施例的详细描述，本领域技术人员将会更加明了本发明的上述以及其他目的、优点和特征。
附图说明
通过阅读下文优选实施方式的详细描述，各种其他的优点和益处对于本领域普通技术人员将变得清楚明了。附图仅用于示出优选实施方式的目的，而并不认为是对本发明的限制。而且在整个附图中，用相同的参考符号表示相同的部件。在附图中：
图1是现有LED驱动电路的架构示意图；
图2是现有LED驱动电路的电路结构示意图；
图3是根据本发明实施例的LED驱动电路的架构示意图；
图4是根据本发明优选实施例的LED驱动电路的架构示意图；
图5是根据本发明一个优选实施例的LED驱动电路的电路结构示意图；
图6是根据本发明另一个优选实施例的LED驱动电路的电路结构示意图。
具体实施方式
下面将参照附图更详细地描述本公开的示例性实施例。虽然附图中显示了本公开的示例性实施例，然而应当理解，可以以各种形式实现本公开而不应被这里阐述的实施例所限制。相反，提供这些实施例是为了能够更透彻地理解本公开，并且能够将本公开的范围完整的传达给本领域的技术人员。需要说明的是，本发明实施例和优选实施例中的技术特征在不冲突的前提下可以相互结合。
针对现有技术中问题，有必要设计一款LED驱动电路，使得其在连接恒功率电子镇流器或者磁环自激驱动的电子镇流器时，能降低电子镇流器输出功率，使LED灯管工作在设计功率以内，保证LED灯管的正常使用以及产品寿命。
图3是根据本发明实施例的LED驱动电路架构示意图。本发明实施例提供的LED驱动电路可以直接与现有的LED驱动电路的模块配合工作。如图3所示，根据本发明实施例的LED驱动电路包括反馈控制电路13和负载阻抗增加电路14，其可以直接与灯丝模拟电路10、整流桥11、功率变换电路12配合工作，整个LED驱动电路用于在上电后驱动至少一个LED发光工作，图3仅示出了一个LED。优选地，负载阻抗增加电路14可以设置在整流桥11和上述的LED之间。
在本实施例中，反馈控制电路13采集LED的工作电流，并与预定的阈值进行比较，当LED的工作电流大于等于阈值时，驱动负载阻抗增加电路14工作，当LED的工作电流小于阈值时，负载阻抗增加电路14不工作；
负载阻抗增加电路14工作时，增加LED驱动装置的负载等效阻抗。
本实施例提供的LED驱动电路，可以在LED功率过高时，提高整个LED驱动电路的负载等效阻抗，从而使电子镇流器降低输出电流，达到降低输出功率的目的。本实施例提供的LED驱动电路适合兼容电子镇流器的LED灯管应用，特别是针对恒功率镇流器或者磁环自激驱动镇流器，能降低镇流器输出功率，使得LED灯管能工作在额定功率， 避免因为过功率使用导致LED灯管损坏或者早衰。
在本发明的一个优选实施例中，可以通过下面的架构实现反馈控制电路13。如图4所示，反馈控制电路13可以包括：电流检测单元131、阈值比较单元132、驱动单元133，电流检测单元131采集LED的工作电流将其转换为比较电压，并输入至阈值比较单元132，阈值比较单元132将比较电压与阈值电压进行比较，当比较电压大于等于阈值电压时，控制驱动单元133开始工作以驱动负载阻抗增加电路14工作，当比较电压小于阈值电压时，驱动单元133不工作，负载阻抗增加电路14不工作。
本优选实施例提供了一种优选地实现反馈控制电路13的方案，基于电流检测单元131、阈值比较单元132、驱动单元133即可完全实现反馈控制电路13的功能，架构简洁且控制逻辑明确。在本优选实施例提供的方案中，采用了将电流转换为电压进行比较的方式，这样可以大幅简化电路结构，较低成本。此时，上述的阈值即为电压阈值。
在上述实施例中，电流检测单元131可以直接基于采样电阻、变压器或者霍尔传感器实现，即使用采样电阻、变压器、霍尔传感器都可以实现采集电流的功能。
进一步的，如图4所示，负载阻抗增加电路14可以通过负载阻抗增加元件141和与负载阻抗增加元件141并联的开关元件142实现，开关元件142导通时，负载阻抗增加元件141被旁路，LED驱动电路的负载等效阻抗没有变化；开关元件142断开时，负载阻抗增加元件141接入LED驱动电路，增加LED驱动电路的负载等效阻抗。
如图4所示，负载阻抗增加电路14可以设置在整流桥11与功率变换电路12之间，负载阻抗增加元件141可以通过与整流桥11和功率变换电路12串联的电感实现，开关元件142则可以通过功率三极管、场效应管或者继电器等实现。开关元件142受LED电流的控制，在LED回路串入电流检测单元131，通过阈值比较，把比较结果输入到驱动单元133，由驱动单元133控制开关元件142的导通和断开。电流检测单元131可以反馈LED的电流大小，该电流与设定的阈值进行比较，如果流过LED的电流比设定的阈值小，驱动单元133使开关元件142导通，负载阻抗增加元件141被短路，工作状态不变；当流过LED的电流比设定的阈值大，驱动单元133使开关K断开，负载阻抗增加元件 141被接入到整流桥11和功率变换电路12之间，增加LED驱动电路的负载等效阻抗。在具体实现比较LED工作电流和预定的阈值大小时，可以将电流装换为电压进行比较，此时预定的阈值要设置为阈值电压。另外，也可以考虑采用直接通过分压电阻等比例采样电压，再与阈值电压进行比较的方式。
负载阻抗增加元件141可以通过电感实现，是因为电子镇流器输出的是高频电压和高频电流，电感在高频电流下呈现一定的阻抗值，当电感被接入电路时，该阻抗值与后续功率变换电路形成串联的关系，从而可以提高负载等效阻抗，使电子镇流器降低输出电流，达到降低输出功率的目的。同时，电感与后续功率变换电路串联，也可以改变负载阻抗特性，针对采用类似电荷泵方式实现无源功率因数校正的电子镇流器，可以降低输入电流总谐波失真。
基于上述电路架构，在具体实现时，可以建立如图5所示的电路结构。
如图5所示，整流桥11由二极管D1、D2、D3和D4组成，负载阻抗增加电路14设置在整流桥11和功率变换电路12之间，其包括电感L，继电器K1，继电器K1在没有激励的情况下是常闭合的。电流检测单元131通过采样电阻Rs实现，电流采样电阻Rs串入LED回路中，LED电流流过采样电阻Rs产生对应的电压，即比较电压。阈值比较单元132基于比较器U1实现，另外，出于限流的考虑，可以增设第一电阻R1、第二电阻R2、第三电阻Rfb、第四电阻Rd，比较电压经过第一电阻R1反馈到比较器U1的正端，阈值电压Vref经过第二电阻R2接入比较器U1的负端；比较器U1输出端一方面通过第三电阻Rfb反馈到正端，另一方面通过第四电阻Rd驱动驱动单元133包括的开关三极管Q1。开关三极管Q1的集电极通过限流电阻R3连接到继电器K1驱动绕组限流电阻，R3用于限制流过继电器K1驱动绕组的电流，驱动绕组另外一头接电源Vcc，同时驱动绕组反向并联续流二极管Dr，用于提供驱动绕组在开关三极管Q1关断时的续流回路。
由于继电器K1在没有激励时是常闭合，电路上电后继电器K1保持闭合，电感L被短路，电路正常工作，此时有电流流入LED，并通过采样电阻Rs检测。如果流入LED的电流比设定的阈值小，比较器U1的负端比正端大，比较器U1输出低电平，开关三极管Q1保持关断， 继电器K的驱动绕组没有激励电流流过，继电器K1保持闭合；如果流入LED的电流比设定的阈值大，比较器U1的负端比正端小，比较器U1输出高电平，开关三极管Q1导通，电源Vcc提供电流流入继电器K1驱动绕组，使得继电器K1断开，电感L接入电路，从而降低电子镇流器输出功率，减少流入LED的电流。
第三电阻Rfb用于正反馈，当比较器U1输出高电平时，通过第三电阻Rfb反馈到正端输入，即使由于LED电流减少导致经过采样电阻Rs反馈的比较电压降低，由于第三电阻Rfb的反馈，使得比较器U1的正端比负端大，比较器U1保持高电平输出。
进一步的，基于上述电路架构，在具体实现时，还可以建立如图6所示的电路结构。
在图6所示的电路中，电流检测单元131和阈值比较单元132与图5所示的电路中的电流检测单元131和阈值比较单元132结构相同。负载阻抗增加电路14包括电感L和场效应管K2，电感L两端并联场效应管K2，场效应管K2的门极驱动来自整流桥11的母线，经过第一分压电阻RA和第二分压电阻RB分压接入，在场效应管K2的门极和源极接入稳压二极管Dz用于限制驱动电压。LED电流通过采样电阻Rs检测并反馈到比较器U1的正端，阈值电压Vref经过第二电阻R2接入比较器U1的负端，U1的输出端一方面通过第三电阻Rfb反馈到正端输入，另一方面通过第四电阻Rd接入光耦模块U2，光耦模块U2用于提供驱动关断信号，控制场效应管K2导通或关断。
电路上电时整流桥的母线电压通过第一分压电阻RA和第二分压电阻RB提供驱动偏置给场效应管K2，使得场效应管K2饱和导通，在流入LED的电流不大时，经过采样电阻Rs反馈的比较电压比电压阈值Vref小，比较器U1输出低电平，没有驱动电流流过光耦模块U2，光耦模块U2保持关断，开关K保持闭合导通，从而旁路电感L，不影响原来的工作；当电子镇流器输出功率过大时，流入LED的电流变大，超过设定的阈值，比较器U1的正端比负端大，比较器U1输出高电平驱动光耦模块U2，光耦模块U2的导通使得场效应管K2门极电压拉低，场效应管K2断开，电感L被串入电路中，从而降低电子镇流器输出功率。
在本发明的一个实施例中还提供了一种LED灯管，其包括上述任 一LED驱动电路和与LED驱动电路连接的至少一个LED，LED驱动电路用于在上电后驱动上述至少一个LED发光工作。
本发明实施例提供了一种LED驱动电路，适合兼容电子镇流器的LED灯管应用，特别是针对恒功率镇流器或者磁环自激驱动镇流器，该驱动电路能降低镇流器输出功率，使得LED灯管能工作在额定功率，避免因为过功率使用导致LED损坏或者早衰，同时，对使用无源功率因数校正的电子镇流器，该驱动能进一步改善输入电流谐波失真。
在此处所提供的说明书中，说明了大量具体细节。然而，能够理解，本发明的实施例可以在没有这些具体细节的情况下实践。在一些实例中，并未详细示出公知的方法、结构和技术，以便不模糊对本说明书的理解。
类似地，应当理解，为了精简本公开并帮助理解各个发明方面中的一个或多个，在上面对本发明的示例性实施例的描述中，本发明的各个特征有时被一起分组到单个实施例、图、或者对其的描述中。然而，并不应将该公开的方法解释成反映如下意图：即所要求保护的本发明要求比在每个权利要求中所明确记载的特征更多的特征。更确切地说，如下面的权利要求书所反映的那样，发明方面在于少于前面公开的单个实施例的所有特征。因此，遵循具体实施方式的权利要求书由此明确地并入该具体实施方式，其中每个权利要求本身都作为本发明的单独实施例。
本领域那些技术人员可以理解，可以对实施例中的设备中的模块进行自适应性地改变并且把它们设置在与该实施例不同的一个或多个设备中。可以把实施例中的模块或单元或组件组合成一个模块或单元或组件，以及此外可以把它们分成多个子模块或子单元或子组件。除了这样的特征和/或过程或者单元中的至少一些是相互排斥之外，可以采用任何组合对本说明书(包括伴随的权利要求、摘要和附图)中公开的所有特征以及如此公开的任何方法或者设备的所有过程或单元进行组合。除非另外明确陈述，本说明书(包括伴随的权利要求、摘要和附图)中公开的每个特征可以由提供相同、等同或相似目的的替代特征来代替。
此外，本领域的技术人员能够理解，尽管在此所述的一些实施例包括其它实施例中所包括的某些特征而不是其它特征，但是不同实施 例的特征的组合意味着处于本发明的范围之内并且形成不同的实施例。例如，在权利要求书中，所要求保护的实施例的任意之一都可以以任意的组合方式来使用。
本发明的各个部件实施例可以以硬件实现，或者以在一个或者多个处理器上运行的软件模块实现，或者以它们的组合实现。本领域的技术人员应当理解，可以在实践中使用微处理器或者数字信号处理器(DSP)来实现根据本发明实施例的LED驱动电路中的一些或者全部部件的一些或者全部功能。本发明还可以实现为用于执行这里所描述的方法的一部分或者全部的设备或者装置程序(例如，计算机程序和计算机程序产品)。这样的实现本发明的程序可以存储在计算机可读介质上，或者可以具有一个或者多个信号的形式。这样的信号可以从因特网网站上下载得到，或者在载体信号上提供，或者以任何其他形式提供。
应该注意的是上述实施例对本发明进行说明而不是对本发明进行限制，并且本领域技术人员在不脱离所附权利要求的范围的情况下可设计出替换实施例。在权利要求中，不应将位于括号之间的任何参考符号构造成对权利要求的限制。单词“包含”不排除存在未列在权利要求中的元件或步骤。位于元件之前的单词“一”或“一个”不排除存在多个这样的元件。本发明可以借助于包括有若干不同元件的硬件以及借助于适当编程的计算机来实现。在列举了若干装置的单元权利要求中，这些装置中的若干个可以是通过同一个硬件项来具体体现。单词第一、第二、以及第三等的使用不表示任何顺序。可将这些单词解释为名称。
至此，本领域技术人员应认识到，虽然本文已详尽示出和描述了本发明的多个示例性实施例，但是，在不脱离本发明精神和范围的情况下，仍可根据本发明公开的内容直接确定或推导出符合本发明原理的许多其他变型或修改。因此，本发明的范围应被理解和认定为覆盖了所有这些其他变型或修改。

Claims (14)

  1. 一种LED驱动电路，包括：反馈控制电路、负载阻抗增加电路，其中，
    所述反馈控制电路采集LED的工作电流，并与预定的阈值进行比较，当所述LED的工作电流大于等于所述阈值时，驱动所述负载阻抗增加电路工作，当所述LED的工作电流小于所述阈值时，所述负载阻抗增加电路不工作；
    所述负载阻抗增加电路工作时，增加所述LED驱动电路的负载等效阻抗。
  2. 根据权利要求1所述的LED驱动电路，其中，还包括：整流桥，所述负载阻抗增加电路设置在所述整流桥和所述LED之间。
  3. 根据权利要求2所述的LED驱动电路，其中，所述负载阻抗增加电路
    包括：负载阻抗增加元件和与所述负载阻抗增加元件并联的开关元件，所述开关元件导通时，所述负载阻抗增加元件被旁路，所述开关元件断开时，所述负载阻抗增加元件接入所述LED驱动电路，增加所述LED驱动电路的负载等效阻抗。
  4. 根据权利要求3所述的LED驱动电路，其中，所述开关元件包括：功率三极管、场效应管或者继电器。
  5. 根据权利要求3所述的LED驱动电路，其中，所述阈值为阈值电压；
    所述反馈控制电路包括：电流检测单元、阈值比较单元、驱动单元，所述电流检测单元采集所述LED的工作电流将其转换为比较电压，并输入至所述阈值比较单元，所述阈值比较单元将所述比较电压与所述阈值电压进行比较，当所述比较电压大于等于所述阈值电压时，控制所述驱动单元开始工作以驱动所述负载阻抗增加电路工作，当所述比较电压小于所述阈值电压时，所述驱动单元不工作，所述负载阻抗增加电路不工作。
  6. 根据权利要求5所述的LED驱动电路，其中，所述电流检测单元包括：采样电阻、变压器或者霍尔传感器。
  7. 根据权利要求6所述的LED驱动电路，其中，所述电流检测单 元包括：采样电阻，所述采样电阻与所述LED串联，所述LED的工作电流流过所述采样电阻产生所述比较电压。
  8. 根据权利要求7所述的LED驱动电路，其中，所述阈值比较单元包括：比较器，所述采样电阻连接至所述比较器的正端，所述阈值电压接入所述比较器的负端，所述比较器的输出端连接至所述驱动单元，所述比较器的输出端还连接至所述比较器的正端。
  9. 根据权利要求8所述的LED驱动电路，其中，所述阈值比较单元还包括：第一电阻、第二电阻、第三电阻、第四电阻，所述采样电阻通过所述第一电阻连接至所述比较器的正端，所述阈值电压通过所述第二电阻接入所述比较器的负端，所述比较器的输出端通过所述第三电阻连接至所述比较器的正端，所述比较器的输出端通过所述第四电阻连接至所述驱动单元。
  10. 根据权利要求5所述的LED驱动电路，其中，所述驱动单元包括：开关三极管、限流电阻、续流二极管，所述开关三极管的基极连接至所述阈值比较单元的输出端，所述开关三极管的发射极接地，所述开关三极管的集电极通过所述限流电阻连接至所述续流二极管，所述续流二极管与所述负载阻抗增加电路的开关元件反向并联。
  11. 根据权利要求10所述的LED驱动电路，其中，还包括：功率变换电路；
    所述负载阻抗增加元件为阻抗电感，所述开关元件为继电器，所述继电器包括：驱动绕组和继电开关，所述驱动绕组的一端通过所述限流电阻连接至所述开关三极管的集电极，所述驱动绕组的另一端连接至电源，所述驱动绕组与所述续流二极管反向并联，所述继电开关与所述阻抗电感并联，所述阻抗电感两端分别于所述整流桥和所述功率变换电路连接。
  12. 根据权利要求5所述的LED驱动电路，其中，还包括：功率变换电路；
    所述驱动单元包括：光耦模块、第一分压电阻、第二分压电阻、稳压二极管，所述光耦模块的输入端连接至所述阈值比较单元的输出端，所述光耦模块的输出端连接至所述负载阻抗增加电路，所述整流桥的母线通过所述第一分压电阻和所述第二分压电阻连接至所述负载阻抗增加电路的开关元件，所述稳压二极管的两端分别与所述开关元 件的两端连接。
  13. 根据权利要求12所述的LED驱动电路，其中，所述负载阻抗增加元件为阻抗电感，所述开关元件为场效应管，所述整流桥的母线通过所述第一分压电阻和所述第二分压电阻连接至所述场效应管的门极，所述场效应管的门极同时连接至所述光耦模块的输出端，所述场效应管的门极和源极分别与所述稳压二极管的两端连接，所述阻抗电感的两端分别与所述场效应管的源极和漏极连接，所述阻抗电感与所述场效应管的源极连接的一端同时与所述整流桥连接，所述阻抗电感与所述场效应管的漏极连接的一端同时与所述功率变换电路连接。
  14. 一种LED灯管，包括权利要求1-11任一项所述的LED驱动电路和与所述的LED驱动电路连接的至少一个LED，所述LED驱动电路用于在上电后驱动所述至少一个LED发光工作。
PCT/CN2017/095673 2016-08-02 2017-08-02 Led驱动电路及led灯管 WO2018024220A1 (zh)

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Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018024218A1 (zh) * 2016-08-02 2018-02-08 欧普照明股份有限公司 一种基于电子镇流器控制电子控制电路的装置及照明灯具
CN109788599A (zh) * 2017-11-14 2019-05-21 通用电气照明解决方案有限公司 Led灯的保护电路
CN110351920B (zh) * 2018-04-08 2022-05-27 朗德万斯公司 驱动器和照明模块
US20210126523A1 (en) * 2020-01-19 2021-04-29 Tong Chen Electric power conversion system

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100181925A1 (en) * 2009-01-21 2010-07-22 Altair Engineering, Inc. Ballast/Line Detection Circuit for Fluorescent Replacement Lamps
CN102595736A (zh) * 2012-03-01 2012-07-18 杭州乐图光电科技有限公司 一种兼容电子镇流器的led驱动电源
CN104797058A (zh) * 2015-04-30 2015-07-22 杰华特微电子（杭州）有限公司 阻尼电路及具有阻尼电路的led驱动电路
CN205124089U (zh) * 2015-11-26 2016-03-30 欧普照明股份有限公司 一种led驱动电路及led灯
CN105715979A (zh) * 2015-04-16 2016-06-29 莱特尔科技公司 无起火和电击危险的具有宽范围输入电压和频率的线性固态照明
CN106102253A (zh) * 2016-08-02 2016-11-09 欧普照明股份有限公司 Led驱动电路及led灯管
CN206196082U (zh) * 2016-08-02 2017-05-24 欧普照明股份有限公司 Led驱动电路及led灯管

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI2964000T3 (fi) * 2002-12-19 2023-01-13 Led käyttölaite
US20110089853A1 (en) * 2009-10-17 2011-04-21 General Electric Company Electronic driver apparatus for large area solid-state leds
US9288867B2 (en) 2012-06-15 2016-03-15 Lightel Technologies, Inc. Linear solid-state lighting with a wide range of input voltage and frequency free of fire and shock hazards
US9544959B2 (en) 2012-06-15 2017-01-10 Lightel Technologies, Inc. Solid-state lighting compatible with ballasts and operable with AC mains
US9420663B1 (en) 2015-04-16 2016-08-16 Aleddra Inc. Linear solid-state lighting with an arc prevention switch mechanism free of fire and shock hazards
US9801241B2 (en) 2012-06-15 2017-10-24 Lightel Technologies, Inc. Solid-state lighting without operational uncertainty and free of fire hazard
JP6326309B2 (ja) * 2014-07-02 2018-05-16 ルネサスエレクトロニクス株式会社 アイソレータ、半導体装置及びアイソレータの制御方法
US9763289B2 (en) * 2015-03-31 2017-09-12 Infineon Technologies Austria Ag System and method for a switched-mode power supply
TWI591952B (zh) * 2015-05-15 2017-07-11 立錡科技股份有限公司 諧振式無線電源接收電路及其控制電路與無線電源轉換方法

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100181925A1 (en) * 2009-01-21 2010-07-22 Altair Engineering, Inc. Ballast/Line Detection Circuit for Fluorescent Replacement Lamps
CN102595736A (zh) * 2012-03-01 2012-07-18 杭州乐图光电科技有限公司 一种兼容电子镇流器的led驱动电源
CN105715979A (zh) * 2015-04-16 2016-06-29 莱特尔科技公司 无起火和电击危险的具有宽范围输入电压和频率的线性固态照明
CN104797058A (zh) * 2015-04-30 2015-07-22 杰华特微电子（杭州）有限公司 阻尼电路及具有阻尼电路的led驱动电路
CN205124089U (zh) * 2015-11-26 2016-03-30 欧普照明股份有限公司 一种led驱动电路及led灯
CN106102253A (zh) * 2016-08-02 2016-11-09 欧普照明股份有限公司 Led驱动电路及led灯管
CN206196082U (zh) * 2016-08-02 2017-05-24 欧普照明股份有限公司 Led驱动电路及led灯管

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP3481159A4 *

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