WO2018210166A1 - Led驱动装置及其恒功率调光电路、调光方法 - Google Patents

Led驱动装置及其恒功率调光电路、调光方法 Download PDF

Info

Publication number
WO2018210166A1
WO2018210166A1 PCT/CN2018/086102 CN2018086102W WO2018210166A1 WO 2018210166 A1 WO2018210166 A1 WO 2018210166A1 CN 2018086102 W CN2018086102 W CN 2018086102W WO 2018210166 A1 WO2018210166 A1 WO 2018210166A1
Authority
WO
WIPO (PCT)
Prior art keywords
mos transistor
voltage
reference voltage
module
current
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.)
Ceased
Application number
PCT/CN2018/086102
Other languages
English (en)
French (fr)
Inventor
陈小雨
邓迅升
陈博
麦炎全
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shenzhen Sendis Semiconductor Co Ltd
Original Assignee
Shenzhen Sendis Semiconductor Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shenzhen Sendis Semiconductor Co Ltd filed Critical Shenzhen Sendis Semiconductor Co Ltd
Priority to US16/615,129 priority Critical patent/US10721799B2/en
Priority to EP18803237.9A priority patent/EP3627971A4/en
Publication of WO2018210166A1 publication Critical patent/WO2018210166A1/zh
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • 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
    • H05B45/345—Current stabilisation; Maintaining constant current
    • 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
    • H05B45/32—Pulse-control circuits
    • H05B45/325—Pulse-width modulation [PWM]
    • 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]
    • 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
    • H05B45/395—Linear regulators
    • H05B45/397—Current mirror 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
    • H05B45/59—Circuit arrangements for operating light-emitting diodes [LED] responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits for reducing or suppressing flicker or glow effects
    • 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 invention relates to the technical field of LED illumination, in particular to an LED driving device, a constant power dimming circuit thereof and a dimming method.
  • the traditional linear constant current LED driven PWM dimming implementation is as follows: as shown in FIG. 1, the input PWM signal is converted into a DC reference voltage VREF through an RC filter wave, and the output current of the constant current source circuit is changed according to the DC reference voltage VREF. Thereby dimming is achieved.
  • FIG. 2 and FIG. 3 when the duty ratio of the PWM signal is constant, when the input mains voltage changes, the input power of the linear constant current LED driving system changes accordingly. This can cause flashover and affect the overall lighting effect.
  • an object of the present invention is to provide an LED driving device, a constant power dimming circuit thereof, and a dimming method, which output a voltage having both line voltage compensation information and PWM signal duty ratio information.
  • the input power of the system is kept constant and the flashover phenomenon is reduced when the duty ratio of the PWM signal is constant and the mains input voltage is changed.
  • a constant power dimming circuit for an LED driving device comprising a line voltage compensation module, a modulation module, a filtering module and a constant current source module;
  • the line voltage compensation module detects a change of the line voltage, and outputs a compensation according to the current line voltage size a first reference voltage of the information;
  • the modulation module modulates the first reference voltage according to the externally input PWM signal, and outputs a second reference voltage having compensation information and PWM duty ratio information to the filtering module; filtering by the filtering module After that, the third reference voltage is outputted to the constant current source module, and the constant current source module is controlled to output a constant current to drive the LED load to work.
  • the line voltage compensation module is specifically configured to: when the current line voltage is less than or equal to the threshold voltage, output a first reference voltage that changes according to a preset rule; when the current line voltage is greater than a threshold At the time of voltage, the first reference voltage having the compensation information is output according to the magnitude of the line voltage.
  • the modulation module is specifically configured to: after modulating the first reference voltage according to an externally input PWM signal, outputting a second reference voltage, so that the second reference voltage is occupied.
  • the null ratio is the same as the PWM signal, and the amplitude of the second reference voltage is the same as the first reference voltage.
  • the line voltage compensation module includes a current source, a voltage source, a conversion unit, a first current mirror unit, a second current mirror unit, and a voltage dividing unit;
  • the conversion unit converts to the first current and outputs to the first current mirror unit, and after the first predetermined multiple mirror image processing is performed by the first current mirror unit, the second current is obtained, and the second current and the third current output by the current source are performed.
  • the fourth current obtained after the subtraction is output to the second current mirror unit, and the second current mirror unit performs a second predetermined multiple mirroring process to obtain a fifth current, and the voltage source outputs the reference voltage to the voltage dividing unit, according to the
  • the fifth current controls the magnitude of the first reference voltage outputted by the voltage dividing unit by the voltage dividing unit to obtain a first reference voltage having compensation information.
  • the modulation module includes a signal receiving unit and a modulating unit, and the signal receiving unit receives the externally input PWM signal, performs level shift processing, and outputs the signal to the modulating unit.
  • the first reference voltage is modulated by the modulation unit according to the level-shifted PWM signal, and the second reference voltage is output, so that the duty ratio of the second reference voltage is the same as the PWM signal, and the second reference voltage is The amplitude is the same as the first reference voltage.
  • the conversion unit includes a conversion resistor
  • the first current mirror unit includes a first MOS transistor, a second MOS transistor, a third MOS transistor, and a fourth MOS transistor.
  • a fifth MOS transistor, a sixth MOS transistor, a seventh MOS transistor, and an eighth MOS transistor one end of the conversion resistor is connected to the line voltage output end, and the other end of the conversion resistor is connected to the drain of the first MOS transistor, first a gate of the MOS transistor and a gate of the second MOS transistor
  • a source of the first MOS transistor is grounded, and a substrate of the first MOS transistor is connected to a drain of the third MOS transistor and a gate of the third MOS transistor
  • a gate of the fourth MOS transistor a drain of the second MOS transistor is connected to a drain of the seventh MOS transistor, a gate of the seventh MOS transistor, and a gate of the eighth MOS transistor, and the second MOS transistor The source is grounded, the
  • the second current mirror unit includes a ninth MOS transistor and a tenth MOS transistor, and a drain of the ninth MOS transistor is connected to a drain of the eighth MOS transistor, a gate of the ninth MOS transistor and a gate of the tenth MOS transistor, the source of the ninth MOS transistor and the substrate are grounded; the drain of the tenth MOS transistor is connected to the voltage dividing unit, the The source and substrate of the ten MOS transistors are grounded.
  • the voltage dividing unit includes a first resistor, a second resistor and a first operational amplifier; one end of the first resistor is connected to a positive pole of the voltage source, the first The other end of the resistor is connected to the drain of the tenth MOS transistor, the non-inverting input of the first operational amplifier, and is also grounded through the second resistor; the inverting input of the first operational amplifier is connected to the output of the first operational amplifier and modulation Module.
  • a constant power dimming method for an LED driving device comprising the following steps:
  • the line voltage compensation module detects a change of the line voltage, and outputs a first reference voltage with compensation information according to the current line voltage size;
  • the modulation module modulates the first reference voltage according to an externally input PWM signal, and outputs a second reference voltage having compensation information and PWM duty ratio information to the filtering module;
  • the third reference voltage is outputted to the constant current source module, and the constant current source module is controlled to output a constant current to drive the LED load to work.
  • An LED driving device comprising an LED light string, a rectifying module for rectifying the input alternating current, and a sampling resistor for sampling the LED string current, and a constant power dimming circuit as described above, the input of the rectifying module The end is connected to the alternating current, and the output end of the rectifier module is connected to the constant power dimming circuit and the LED light string, and the constant power dimming circuit is also grounded through the sampling resistor.
  • the constant power dimming circuit of the LED driving device comprises a line voltage compensation module, a modulation module, a filtering module and a constant current source module; detecting, by the line voltage compensation module, a change of the line voltage, and outputting a first reference voltage having compensation information according to the current line voltage magnitude; the modulation module modulating the first reference voltage according to the externally input PWM signal, Outputting a second reference voltage having compensation information and PWM duty ratio information to the filtering module; filtering the filter module to output a third reference voltage to the constant current source module, and controlling the constant current source module to output a constant current to drive the LED load to work
  • the input power of the system is kept constant when the duty ratio of the PWM signal is constant and the mains input voltage is changed. , reduce the phenomenon of flashover.
  • FIG. 1 is a circuit diagram of a prior art LED dimming device.
  • Figure 2 is a schematic diagram of a constant duty cycle of a PWM signal.
  • Figure 3 is a graph of system input power - input mains.
  • FIG. 4 is a schematic diagram of an LED driving device provided by the present invention.
  • FIG. 5 is a circuit diagram of a line voltage compensation module in a constant power dimming circuit of an LED driving device provided by the present invention.
  • FIG. 6 is a circuit diagram of a preferred embodiment of a line voltage compensation module in a constant power dimming circuit of an LED driving device provided by the present invention.
  • FIG. 7 is a circuit diagram of a signal receiving unit in a constant power dimming circuit of an LED driving device provided by the present invention.
  • FIG. 8 is a circuit diagram of a modulation unit in a constant power dimming circuit of an LED driving device according to the present invention.
  • FIG. 9 is a circuit diagram of a filtering module in a constant power dimming circuit of an LED driving device provided by the present invention.
  • FIG. 10 is a graph showing an input line voltage, a first reference voltage, and a second reference unit in a constant power dimming circuit of an LED driving device provided by the present invention.
  • FIG. 11 is a flow chart of a constant power dimming method of an LED driving device provided by the present invention.
  • the object of the present invention is to provide an LED driving device, a constant power dimming circuit thereof, and a dimming method, which have line voltage compensation information through the output. And the voltage of the PWM signal duty ratio control to control the constant current source circuit, the input power of the system is kept constant and the flashover phenomenon is reduced when the duty ratio of the PWM signal is constant and the mains input voltage is changed.
  • the LED driving device comprises an LED light string 11, a rectifying module 12 for rectifying the input alternating current, and a sampling resistor Rs for sampling the current of the LED string 11, and further comprising adjusting the LED lamp.
  • the rectifier module 12 is a rectifier bridge.
  • the constant power dimming circuit 13 includes a line voltage compensation module 10, a modulation module 20, a filtering module 30, and a constant current source module 40.
  • the line voltage compensation module 10 is connected to a line voltage output terminal VAC, and the line voltage compensation is performed.
  • the module 10 is further connected to the filter module 30 through the modulation module 20, the filter module 30 is also connected to the constant current source module 40, and the line voltage compensation module 10 detects the change of the line voltage, and outputs the first with the compensation information according to the current line voltage size.
  • the modulation module 20 modulates the first reference voltage according to an externally input PWM signal, and outputs a second reference voltage having compensation information and PWM duty ratio information to the filtering module 30; after filtering by the filtering module 30
  • the third reference voltage is output to the constant current source module 40, and the constant current source module 40 is controlled to output a constant current to drive the LED load to operate.
  • the invention detects the change of the line voltage by the line voltage compensation module 10, and outputs a corresponding first reference voltage with compensation information according to the magnitude of the line voltage, that is, the first reference voltage is a voltage signal after the line voltage is compensated and corrected, and then the modulation module 20 modulating the first reference voltage according to the received PWM signal, synthesizing the signal characteristic of the PWM signal and the signal characteristic of the first reference voltage, and outputting a second reference voltage having the compensation information and the PWM duty ratio information to the filter
  • the module 30, that is, the second reference voltage has the characteristics of the PWM signal and the second reference voltage at the same time
  • the filter module 30 filters and converts the second reference voltage, and outputs a DC third reference voltage according to the third reference.
  • the output current of the constant current source module 40 is controlled to drive the LED load. Since the third reference voltage input to the constant current source module 40 also has the characteristics of the PWM signal and the second reference voltage, when dimming, when When the duty cycle of the PWM signal changes, the input power of the system changes linearly, and when the duty cycle of the PWM signal is the same, the input Voltage variations do not cause changes in input power of the system is linear, substantially constant, improving the overall lighting effect.
  • the line voltage compensation module 10 is specifically configured to output a first reference voltage that changes according to a preset rule when the current line voltage is less than or equal to the threshold voltage; and when the current line voltage is greater than the threshold voltage, output according to the magnitude of the line voltage
  • the first reference voltage of the compensation information that is, when the line voltage is generated due to fluctuations in the mains voltage, the line voltage compensation module 10 outputs a first reference voltage that changes according to a preset rule to ensure normal operation of the LED load, specifically according to the preset
  • the first reference voltage that is regularly changed may be a first reference voltage whose voltage value is constant, or a first reference voltage whose voltage value gradually rises, and the like, which may be implemented by different circuits, which is not limited by the present invention;
  • the line voltage compensation module 10 outputs a first reference voltage having compensation information according to the magnitude of the line voltage. For example, when the line voltage is greater than the threshold voltage, the output first reference voltage decreases as the line voltage increases. The line voltage is increased and increased, and the compensation is achieved
  • the modulation module 20 is specifically configured to: after modulating the first reference voltage according to an externally input PWM signal, outputting a second reference voltage, so that a duty ratio of the second reference voltage is the same as a PWM signal, and the second reference The magnitude of the voltage is the same as the first reference voltage. That is, the present invention receives the externally input PWM signal and the first reference signal output by the line voltage compensation module 10 through the modulation module 20, modulates the first reference voltage according to the PWM signal, and outputs the PWM signal characteristic and the first reference simultaneously.
  • a second reference voltage of the voltage characteristic specifically, the duty ratio of the output second reference voltage is the same as the PWM signal, and the amplitude of the second reference voltage is the same as the first reference voltage, which does not affect the normal dimming, It is also possible to maintain a constant input power of the system when the input mains voltage fluctuates by the compensated voltage amplitude.
  • the line voltage compensation module 10 includes a current source I0, a voltage source U0, a conversion unit 101, a first current mirror unit 102, a second current mirror unit 103, and a voltage dividing unit 104.
  • the conversion unit 101 is connected to the line voltage output terminal VAC, and is also connected to the second current mirror unit 103 via the first current mirror unit 102.
  • the second current mirror unit 103 is also connected to the voltage dividing unit 104, and the voltage dividing unit 104 is connected to the Voltage source U0 and modulation module 20 are described.
  • the input line voltage is converted into a first current by the conversion unit 101 and output to the first current mirror unit 102, and the first current mirror unit 102 performs a first predetermined multiple image processing to obtain a second current, the second current and current.
  • the fourth current obtained by subtracting the third current outputted by the source I0 is output to the second current mirror unit 103, and the second current mirror unit 103 performs a second predetermined multiple image processing to obtain a fifth current, the voltage source.
  • U0 outputs a reference voltage to the voltage dividing unit 104, and controls a magnitude of the first reference voltage outputted by the voltage dividing unit 104 according to the fifth current to obtain a first reference voltage having compensation information, and the present invention
  • the output voltage of the voltage dividing unit 104 is controlled, and the magnitude of the first reference voltage is determined according to a preset multiple of the current mirror.
  • the specific parameter setting in the pressure module can flexibly change the compensation relationship between the first reference voltage and the input line voltage, and further improve the compensation output. Correctness.
  • the conversion unit 101 includes a conversion resistor R0
  • the first current mirror unit 102 includes a first MOS transistor M1, a second MOS transistor M2, a third MOS transistor M3, a fourth MOS transistor M4, and a fifth MOS transistor M5.
  • the second current mirror unit 103 includes a ninth MOS transistor M9 and a tenth MOS transistor M10, and a drain of the ninth MOS transistor M9 is connected to a drain of the eighth MOS transistor M8, a gate of the ninth MOS transistor M9, and a gate of the tenth MOS transistor M10, a source of the ninth MOS transistor M9 and a substrate are grounded; a drain of the tenth MOS transistor M10 is connected to the voltage dividing unit 104, the tenth MOS transistor M10 Both the source and the substrate are grounded.
  • the first MOS transistor M1, the second MOS transistor M2, the third MOS transistor M3, the fourth MOS transistor M4, the ninth MOS transistor M9, and the tenth MOS transistor M10 are N-channel MOS transistors.
  • the fifth MOS transistor M5, the sixth MOS transistor M6, the seventh MOS transistor M7, and the eighth MOS transistor M8 are P-channel MOS transistors.
  • the voltage dividing unit 104 includes a first resistor R1, a second resistor R2 and a first operational amplifier A1; one end of the first resistor R1 is connected to the anode of the voltage source U0, and the other end of the first resistor R1 is connected to the tenth
  • the drain of the MOS transistor M10, the non-inverting input terminal of the first operational amplifier A1, is also grounded through the second resistor R2; the inverting input terminal of the first operational amplifier A1 is connected to the output terminal of the first operational amplifier A1 and the modulation module 20 .
  • the invention converts the input line voltage VAC into the first current I1 through the conversion resistor R0, and passes through the first MOS transistor M1, the second MOS transistor M2, the third MOS transistor M3, the fourth MOS transistor M4, the fifth MOS transistor M5,
  • the first current mirror unit 102 formed by the sixth MOS transistor M6, the seventh MOS transistor M7, and the eighth MOS transistor M8 outputs a second current I2, which is the first current mirror unit 102 in the embodiment.
  • the fifth current is outputted to the voltage dividing unit 104, that is, the intermediate point between the first resistor R1 and the second resistor R2, thereby changing the first resistor R1 and
  • the voltage-divided output of the second resistor R2 outputs a first reference voltage (V_LVC in this embodiment) having compensation information.
  • the output first reference voltage V_LVC is equal to the voltage division value of the reference voltage VREF1 output by the voltage source U0 through the first resistor R1 and the second resistor R2;
  • the output first reference voltage V_LVC will decrease as the line voltage increases, and rises as the line voltage decreases.
  • FIG. 6 is a circuit diagram of the line voltage compensation module 10 in the preferred embodiment of the present invention, different from the above embodiment, in the preferred embodiment, under the conversion resistor R0.
  • the first capacitor C1 for filtering is added, one end of the first capacitor C1 is connected to the other end of the conversion resistor R0, and the other end of the first capacitor C1 is grounded, and the first reference is effectively reduced by the filtering effect of the first capacitor C1.
  • the fluctuation of the voltage V_LVC can finally reduce the fluctuation of the third reference voltage outputted to the constant current source module 40, thereby reducing the ripple of the constant current source output.
  • the modulation module 20 includes a signal receiving unit 201 and a modulating unit 202.
  • the signal receiving unit 201 is connected to a modulating unit 202, and the modulating unit 202 is further connected to the voltage dividing unit.
  • the unit 104 and the filtering module 30 receive the externally input PWM signal by the signal receiving unit 201 (shown in FIG. 7). Since the voltage of the external input PWM signal may not match the power supply voltage inside the driving system, the signal receiving unit 201 is passed.
  • the PWM signal is level-shifted and then output to the modulation unit 202, and the PWM signal after the level shift processing and the first reference voltage V_LVC output by the voltage dividing unit 104 are received by the modulation unit 202, and the first reference voltage V_LVC is applied. Modulation is performed to generate a second reference voltage V_ALG having the same duty cycle as the PWM signal and having the same magnitude as the first reference voltage V_LVC to the filtering module 30.
  • the signal receiving unit 201 includes a shifter, a first inverter A21 and a second inverter A22
  • the modulation unit 202 includes a first switch S1 and a second switch S2
  • the shifter One end of the inverter is connected to the PWM signal input end
  • the other end of the shifter is connected to the input end of the first inverter A21
  • the output end of the first inverter A21 is connected to the control end of the second switch S2 and the second reverse
  • the output end of the second inverter A22 is connected to the control end of the first switch S1
  • the two terminals of the first switch S1 are respectively connected to the output end of the first operational amplifier A1 and filtering
  • the module 30 has two connection ends of the second switch S2 connected to the filter module 30 and the ground.
  • the in-phase signals PWM_P and PWM_N are generated by the two-stage inverter for driving the first switch S1 and the second switch S2, respectively, by controlling the first switch S1 and the first
  • the second switch S2 modulates the first reference voltage V_LVC to generate a second reference voltage V_ALG that is the same as the PWM signal duty cycle and has the same amplitude as the first reference voltage V_LVC, and is output to the constant current source module 40 after subsequent filtering processing.
  • the dimming is implemented by controlling the output current of the constant current source, so that when the duty ratio of the PWM signal changes, the input power of the system changes linearly; while the input of the same PWM duty cycle is input, when the input mains voltage changes.
  • the input power of the system remains basically the same, effectively reducing the phenomenon of flashover and improving the overall lighting effect.
  • the filtering module 30 is a first-order RC filter circuit, which includes a third resistor R3 and a second capacitor C2, and the constant current source module 40 includes a second operational amplifier A2 and a high voltage MOS.
  • one end of the third resistor R3 is connected to the connection end of the first switch S1 and the second switch S2, and the other end of the third resistor R3 is connected to the non-inverting input terminal of the second operational amplifier A2, and also passes through the second capacitor C2 is grounded;
  • the inverting input terminal of the second operational amplifier A2 is connected to the source of the high voltage MOS transistor M0, grounded through the sampling resistor Rs, and the output terminal of the second operational amplifier A2 is connected to the gate of the high voltage MOS transistor M0;
  • the drain of the high voltage MOS transistor M0 is connected to the cathode of the LED string 11 to be dimmed.
  • the third reference voltage VREF After filtering the second reference voltage V_ALG by the first-order RC filter circuit composed of the third resistor R3 and the second capacitor C2, the third reference voltage VREF is output, and the DC reference voltage signal has the following characteristics, when the input line voltage is unchanged
  • the third reference voltage VREF changes according to the PWM duty cycle
  • the input power can be linearly changed with the PWM duty ratio to achieve the dimming purpose; when the PWM duty ratio is constant, the third reference voltage VREF is input.
  • the input power does not change with the input line voltage, and the input power is kept constant to improve the illumination effect.
  • (a) in FIG. 10 represents the line voltage, in FIG.
  • the first reference voltage is correspondingly compensated according to the magnitude of the input line voltage.
  • the first reference The voltage output is a constant value, and when it is greater than the threshold voltage Vth, the first reference voltage is no longer a constant value, but decreases as the line voltage increases, and rises as the line voltage decreases.
  • the purpose of voltage compensation is to achieve constant power in constant current driving, and the second reference voltage of the modulated output terminal not only has the amplitude information of the first reference voltage, but also has the duty ratio information of the PWM signal.
  • the input power is linearly converted from the PWM duty cycle to achieve the dimming purpose.
  • the present invention also provides a constant power dimming method for an LED driving device.
  • the constant power dimming method of the LED driving device includes the following steps:
  • the line voltage compensation module detects a change of the line voltage, and outputs a first reference voltage with compensation information according to the current line voltage size;
  • the modulation module modulates the first reference voltage according to the externally input PWM signal, and outputs a second reference voltage having the compensation information and the PWM duty ratio information to the filtering module;
  • the present invention also provides a constant power dimming circuit for an LED driving device. Since the constant power dimming circuit has been described in detail above, it will not be described in detail herein.
  • the constant power dimming circuit of the LED driving device includes a line voltage compensation module, a modulation module, a filtering module, and a constant current.
  • a source module detecting, by the line voltage compensation module, a change of the line voltage, and outputting a first reference voltage having compensation information according to the current line voltage magnitude; the modulation module modulating the first reference voltage according to the externally input PWM signal, and outputting simultaneously a second reference voltage with compensation information and PWM duty cycle information to the filtering module; after filtering by the filtering module, outputting a third reference voltage to the constant current source module, and controlling the constant current source module to output a constant current to drive the LED load to work,
  • the output voltage has the line voltage compensation information and the PWM signal duty ratio information to control the constant current source circuit, and the input power of the system is kept constant when the duty ratio of the PWM signal is constant and the mains input voltage is changed. Flashing phenomenon.

Landscapes

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

Abstract

一种LED驱动装置及其恒功率调光电路、调光方法，所述恒功率调光电路包括线电压补偿模块（10）、调制模块（20）、滤波模块（30）和恒流源模块（40）；由线电压补偿模块（10）检测线电压的变化，根据当前线电压大小输出具有补偿信息的第一参考电压；调制模块（20）根据外部输入的PWM信号对第一参考电压进行调制，输出同时具有补偿信息和PWM占空比信息的第二参考电压至滤波模块（30）；经滤波模块（30）进行滤波后输出第三参考电压至恒流源模块（40），控制恒流源模块（40）输出恒流以驱动LED负载工作，通过输出同时具有线电压补偿信息和PWM占空比信息的电压控制恒流源电路，可在PWM信号的占空比不变而市电输入电压变化时，系统的输入功率保持恒定，减少压闪现象。

Description

LED驱动装置及其恒功率调光电路、调光方法 技术领域
本发明涉及LED照明技术领域，特别涉及LED驱动装置及其恒功率调光电路、调光方法。
背景技术
传统线性恒流LED驱动的PWM调光实现方式为：如图1所示，将输入的PWM信号通过RC滤波电波转换为直流参考电压VREF，根据此直流参考电压VREF改变恒流源电路的输出电流从而实现调光。然而，如图2和图3所示，这样的调光方式在PWM信号的占空比不变时，当输入的市电电压变化时，线性恒流LED驱动系统的输入功率会随之变化，从而会造成压闪，影响整体的照明效果。
因而现有技术还有待改进和提高。
发明内容
鉴于上述现有技术的不足之处，本发明的目的在于提供一种LED驱动装置及其恒功率调光电路、调光方法，通过输出同时具有线电压补偿信息和PWM信号占空比信息的电压来控制恒流源电路，可实现在PWM信号的占空比不变而市电输入电压变化时，系统的输入功率保持恒定，减少压闪现象。
为了达到上述目的，本发明采取了以下技术方案：
一种LED驱动装置的恒功率调光电路，其包括线电压补偿模块、调制模块、滤波模块和恒流源模块；由线电压补偿模块检测线电压的变化，并根据当前线电压大小输出具有补偿信息的第一参考电压；调制模块根据外部输入的PWM信号对所述第一参考电压进行调制，输出同时具有补偿信息和PWM占空比信息的第二参考电压至滤波模块；经滤波模块进行滤波后输出第三参考电压至恒流源模块，控制恒流源模块输出恒流以驱动LED负载工作。
所述的LED驱动装置的恒功率调光电路中，所述线电压补偿模块具体用于，当当前线电压小于等于阈值电压时，输出按预设规律变化的第一参考电压；当当前线电压大于阈值电压时，根据线电压的大小输出具有补偿信息的第一参考电压。
所述的LED驱动装置的恒功率调光电路中，所述调制模块具体用于根据外部输入的PWM信号对所述第一参考电压进行调制后输出第二参考电压，使第二 参考电压的占空比与PWM信号相同，第二参考电压的幅值与第一参考电压相同。
所述的LED驱动装置的恒功率调光电路中，所述线电压补偿模块包括电流源、电压源、转换单元、第一电流镜单元、第二电流镜单元和分压单元；输入线电压通过转换单元转换为第一电流后输出至第一电流镜单元，经第一电流镜单元进行第一预设倍数镜像处理后得到第二电流，所述第二电流和电流源输出的第三电流进行减法运算后得到的第四电流输出至第二电流镜单元，经第二电流镜单元进行第二预设倍数镜像处理后得到第五电流，所述电压源输出参考电压至分压单元，根据所述第五电流控制所述参考电压经分压单元分压后输出的第一参考电压的大小，得到具有补偿信息的第一参考电压。
所述的LED驱动装置的恒功率调光电路中，所述调制模块包括信号接收单元和调制单元，由信号接收单元接收外部输入的PWM信号，对其进行电平移位处理后输出至调制单元，由所述调制单元根据经电平移位处理后的PWM信号对所述第一参考电压进行调制，输出第二参考电压，使第二参考电压的占空比与PWM信号相同，第二参考电压的幅值与第一参考电压相同。
所述的LED驱动装置的恒功率调光电路中，所述转换单元包括转换电阻，所述第一电流镜单元包括第一MOS管、第二MOS管、第三MOS管、第四MOS管、第五MOS管、第六MOS管、第七MOS管和第八MOS管；所述转换电阻的一端连接线电压输出端，所述转换电阻的另一端连接第一MOS管的漏极、第一MOS管的栅极和第二MOS管的栅极；所述第一MOS管的源极接地，所述第一MOS管的衬底连接第三MOS管的漏极、第三MOS管的栅极和第四MOS管的栅极；所述第二MOS管的漏极连接第七MOS管的漏极、第七MOS管的栅极和第八MOS管的栅极，所述第二MOS管的源极接地，所述第二MOS管的衬底连接第四MOS管的漏极；所述第三MOS管的源极和衬底均接地；所述第四MOS管的源极和衬底均接地；所述第五MOS管的源极和衬底连接VDD供电端，所述第五MOS管的栅极连接第五MOS管的漏极、第六MOS管的栅极和第七MOS管的衬底；所述第六MOS管的源极和衬底连接VDD供电端，所述第六MOS管的漏极连接第八MOS管的衬底；所述第七MOS管的源极连接VDD供电端；所述第八MOS管的源极连接VDD供电端，所述第八MOS管的漏极连接电流源的一端和第二电流镜单元，电流源的另一端接地。
所述的LED驱动装置的恒功率调光电路中，所述第二电流镜单元包括第九MOS管和第十MOS管，所述第九MOS管的漏极连接第八MOS管的漏极、第九MOS管的栅极和第十MOS管的栅极，所述第九MOS管的源极和衬底均接地；所述第十MOS管的漏极连接所述分压单元，所述第十MOS管的源极和衬底均接地。
所述的LED驱动装置的恒功率调光电路中，所述分压单元包括第一电阻、第二电阻和第一运算放大器；所述第一电阻的一端连接电压源的正极，所述第一电阻的另一端连接第十MOS管的漏极、第一运算放大器的同相输入端、还通过第二电阻接地；所述第一运算放大器的反相输入端连接第一运算放大器的输出端和调制模块。
一种LED驱动装置的恒功率调光方法，其包括如下步骤：
A、由线电压补偿模块检测线电压的变化，并根据当前线电压大小输出具有补偿信息的第一参考电压；
B、调制模块根据外部输入的PWM信号对所述第一参考电压进行调制，输出同时具有补偿信息和PWM占空比信息的第二参考电压至滤波模块；
C、经滤波模块进行滤波后输出第三参考电压至恒流源模块，控制恒流源模块输出恒流以驱动LED负载工作。
一种LED驱动装置，包括LED灯串、用于对输入交流电进行整流的整流模块和对LED灯串电流进行采样的采样电阻，以及如上所述的恒功率调光电路，所述整流模块的输入端连接交流电，所述整流模块的输出端连接恒功率调光电路和LED灯串，所述恒功率调光电路还通过采样电阻接地。
相较于现有技术，本发明提供的LED驱动装置及其恒功率调光电路、调光方法中，所述LED驱动装置的恒功率调光电路包括线电压补偿模块、调制模块、滤波模块和恒流源模块；由线电压补偿模块检测线电压的变化，并根据当前线电压大小输出具有补偿信息的第一参考电压；调制模块根据外部输入的PWM信号对所述第一参考电压进行调制，输出同时具有补偿信息和PWM占空比信息的第二参考电压至滤波模块；经滤波模块进行滤波后输出第三参考电压至恒流源模块，控制恒流源模块输出恒流以驱动LED负载工作，通过输出同时具有线电压补偿信息和PWM信号占空比信息的电压来控制恒流源电路，可实现在PWM信号的 占空比不变而市电输入电压变化时，系统的输入功率保持恒定，减少压闪现象。
附图说明
图1为现有技术中LED调光装置的电路图。
图2为PWM信号的恒定占空比示意图。
图3为系统输入功率-输入市电的曲线图。
图4为本发明提供的LED驱动装置的原理图。
图5为本发明提供的LED驱动装置的恒功率调光电路中线电压补偿模块的电路图。
图6为本发明提供的LED驱动装置的恒功率调光电路中线电压补偿模块优选实施例的电路图。
图7为本发明提供的LED驱动装置的恒功率调光电路中信号接收单元的电路图。
图8为本发明提供的LED驱动装置的恒功率调光电路中调制单元的电路图。
图9为本发明提供的LED驱动装置的恒功率调光电路中滤波模块的电路图。
图10为本发明提供的LED驱动装置的恒功率调光电路中输入线电压、第一参考电压和第二参考单元曲线图。
图11为本发明提供的LED驱动装置的恒功率调光方法的流程图。
具体实施方式
鉴于现有技术中输入市电的不稳定会带来压闪等缺点，本发明的目的在于提供一种LED驱动装置及其恒功率调光电路、调光方法，通过输出同时具有线电压补偿信息和PWM信号占空比信息的电压来控制恒流源电路，可实现在PWM信号的占空比不变而市电输入电压变化时，系统的输入功率保持恒定，减少压闪现象。
为使本发明的目的、技术方案及效果更加清楚、明确，以下参照附图并举实施例对本发明进一步详细说明。应当理解，此处所描述的具体实施例仅用以解释本发明，并不用于限定本发明。
请参阅图4，本发明提供的LED驱动装置包括LED灯串11、用于对输入交流电进行整流的整流模块12和对LED灯串11电流进行采样的采样电阻Rs，还包括用于调节LED灯串11电流的恒功率调光电路13，所述整流模块12的输入 端连接交流电，所述整流模块12的输出端恒功率调光电路13和LED灯串11，所述恒功率调光电路13还通过采样电阻Rs接地，通过恒功率调光电路13根据PWM信号来控制LED灯串11的电流以实现调光，同时在PWM信号的占空比不变时，系统输入功率在输入市电电压变化时依然保持恒定，有效减少压闪的现象。本实施例中，所述整流模块12为整流桥。
具体地，所述恒功率调光电路13包括线电压补偿模块10、调制模块20、滤波模块30和恒流源模块40所述线电压补偿模块10连接线电压输出端VAC，所述线电压补偿模块10还通过调制模块20连接滤波模块30，所述滤波模块30还连接恒流源模块40，由线电压补偿模块10检测线电压的变化，并根据当前线电压大小输出具有补偿信息的第一参考电压；调制模块20根据外部输入的PWM信号对所述第一参考电压进行调制，输出同时具有补偿信息和PWM占空比信息的第二参考电压至滤波模块30；经滤波模块30进行滤波后输出第三参考电压至恒流源模块40，控制恒流源模块40输出恒流以驱动LED负载工作。
本发明通过线电压补偿模块10检测线电压的变化，根据线电压的大小输出相应的具有补偿信息的第一参考电压，即第一参考电压为线电压经过补偿修正后的电压信号，之后调制模块20根据接收到的PWM信号对所述第一参考电压进行调制，综合PWM信号的信号特征以及第一参考电压的信号特征，输出同时具有补偿信息和PWM占空比信息的第二参考电压至滤波模块30，即此时第二参考电压同时具有PWM信号的特点和第二参考电压的特点，经滤波模块30将第二参考电压进行滤波转换后输出直流第三参考电压，根据所述第三参考电压控制恒流源模块40的输出电流，以驱动LED负载工作，由于输入至恒流源模块40的第三参考电压同样也具有PWM信号和第二参考电压的特点，因此在调光时，当PWM信号占空比变化时，系统的输入功率随之线性改变，而当PWM信号占空比相同时，输入市电电压变化不会引起系统输入功率的线性变化，基本保持恒定，提高了整体的照明效果。
具体来说，所述线电压补偿模块10具体用于当当前线电压小于等于阈值电压时，输出按预设规律变化的第一参考电压；当当前线电压大于阈值电压时，根据线电压的大小输出具有补偿信息的第一参考电压，即在市电电压产生波动造成线电压较小时，线电压补偿模块10将输出按预设规律变化的第一参考电压，保 证LED负载的正常工作，具体按预设规律变化的第一参考电压可以是电压值恒定的第一参考电压，或者电压值逐渐上升的第一参考电压等等，可采用不同的电路实现，本发明对此不作限定；而在线电压较大时，线电压补偿模块10将根据线电压的大小输出具有补偿信息的第一参考电压，例如在线电压大于阈值电压时，输出的第一参考电压随着线电压的增大而减小，随着线电压的减小而增大，依次达到补偿的目的，使得在恒流驱动下，输入功率能保持恒定。
进一步地，所述调制模块20具体用于根据外部输入的PWM信号对所述第一参考电压进行调制后输出第二参考电压，使第二参考电压的占空比与PWM信号相同，第二参考电压的幅值与第一参考电压相同。即本发明通过调制模块20接收外部输入的PWM信号和线电压补偿模块10输出的第一参考信号，根据该PWM信号对所述第一参考电压进行调制，输出同时具有PWM信号特点和第一参考电压特点的第二参考电压，具体来说，输出的第二参考电压的占空比与PWM信号相同，且第二参考电压的幅值与第一参考电压相同，既不影响正常的调光，也能通过补偿后的电压幅值使得在输入市电电压有所波动时，保持系统输入功率的恒定。
具体地，请一并参阅图5，所述线电压补偿模块10包括电流源I0、电压源U0、转换单元101、第一电流镜单元102、第二电流镜单元103和分压单元104，所述转换单元101连接线电压输出端VAC、还通过第一电流镜单元102连接第二电流镜单元103，所述第二电流镜单元103还连接分压单元104，所述分压单元104连接所述电压源U0和调制模块20。
输入线电压通过转换单元101转换为第一电流后输出至第一电流镜单元102，经第一电流镜单元102进行第一预设倍数镜像处理后得到第二电流，所述第二电流和电流源I0输出的第三电流进行减法运算后得到的第四电流输出至第二电流镜单元103，经第二电流镜单元103进行第二预设倍数镜像处理后得到第五电流，所述电压源U0输出参考电压至分压单元104，根据所述第五电流控制所述参考电压经分压单元104分压后输出的第一参考电压的大小，得到具有补偿信息的第一参考电压，本发明通过将电压信号转换为电流信号，之后对该电流信号进行预设倍数的镜像处理，进而控制分压单元104的输出电压大小，及第一参考电压的大小，根据电流镜的预设倍数以及分压模块中的具体参数设置，可灵活改变第一 参考电压与输入线电压之间的补偿关系，进一步提高补偿输出的准确性。
其中，所述转换单元101包括转换电阻R0，所述第一电流镜单元102包括第一MOS管M1、第二MOS管M2、第三MOS管M3、第四MOS管M4、第五MOS管M5、第六MOS管M6、第七MOS管M7和第八MOS管M8；所述转换电阻R0的一端连接线电压输出端，所述转换电阻R0的另一端连接第一MOS管M1的漏极、第一MOS管M1的栅极和第二MOS管M2的栅极；所述第一MOS管M1的源极接地，所述第一MOS管M1的衬底连接第三MOS管M3的漏极、第三MOS管M3的栅极和第四MOS管M4的栅极；所述第二MOS管M2的漏极连接第七MOS管M7的漏极、第七MOS管M7的栅极和第八MOS管M8的栅极，所述第二MOS管M2的源极接地，所述第二MOS管M2的衬底连接第四MOS管M4的漏极；所述第三MOS管M3的源极和衬底均接地；所述第四MOS管M4的源极和衬底均接地；所述第五MOS管M5的源极和衬底连接VDD供电端，所述第五MOS管的栅极连接第五MOS管M5的漏极、第六MOS管M6的栅极和第七MOS管M7的衬底；所述第六MOS管M6的源极和衬底连接VDD供电端，所述第六MOS管M6的漏极连接第八MOS管M8的衬底；所述第七MOS管M7的源极连接VDD供电端；所述第八MOS管M8的源极连接VDD供电端，所述第八MOS管M8的漏极连接电流源I0的一端和第二电流镜单元103，电流源I0的另一端接地。
所述第二电流镜单元103包括第九MOS管M9和第十MOS管M10，所述第九MOS管M9的漏极连接第八MOS管M8的漏极、第九MOS管M9的栅极和第十MOS管M10的栅极，所述第九MOS管M9的源极和衬底均接地；所述第十MOS管M10的漏极连接所述分压单元104，所述第十MOS管M10的源极和衬底均接地。本实施例中，所述第一MOS管M1、第二MOS管M2、第三MOS管M3、第四MOS管M4、第九MOS管M9和第十MOS管M10为N沟道MOS管，所述第五MOS管M5、第六MOS管M6、第七MOS管M7和第八MOS管M8为P沟道MOS管。
所述分压单元104包括第一电阻R1、第二电阻R2和第一运算放大器A1；所述第一电阻R1的一端连接电压源U0的正极，所述第一电阻R1的另一端连接第十MOS管M10的漏极、第一运算放大器A1的同相输入端、还通过第二电阻 R2接地；所述第一运算放大器A1的反相输入端连接第一运算放大器A1的输出端和调制模块20。
本发明通过转换电阻R0将输入线电压VAC转换输出为第一电流I1，通过第一MOS管M1、第二MOS管M2、第三MOS管M3、第四MOS管M4、第五MOS管M5、第六MOS管M6、第七MOS管M7和第八MOS管M8构成的第一电流镜单元102，将第一电流镜像输出第二电流I2，本实施例中所述第一电流镜单元102的第一预设倍数为M1:1，即I1/I2＝M1/1，之后第二电流I2与电流源I0输出的第三电流I3进行减法运算，得到第四电流I4输出至第二电流镜单元103，经过第二电流镜单元103进行第二预设倍数的镜像处理后输出第五电流至分压单元104，即第一电阻R1和第二电阻R2的中间点，从而改变第一电阻R1和第二电阻R2的分压输出，输出具有补偿信息的第一参考电压(本实施例中为V_LVC)，本实施例中所述第二电流镜单元103的第二预设倍数为1:M3，即I4/I5＝1/M3。具体地，当线电压较低时，I2<I3，则I4没有电流，输出第一参考电压V_LVC等于电压源U0输出的参考电压VREF1经过第一电阻R1和第二电阻R2的分压值；当线电压较高时，I2>I3，则I4有电流，输出第一参考电压V_LVC会随着线电压的升高而降低，而随着线电压的降低而升高，具体运算公式如下：
Figure PCTCN2018086102-appb-000001
Figure PCTCN2018086102-appb-000002
Figure PCTCN2018086102-appb-000003
Figure PCTCN2018086102-appb-000004
优选地，在本发明优选实施例中，如图6所示，其为本发明优选实施例中线电压补偿模块10的电路图，与上述实施例不同的是，优选实施中在转换电阻R0的下方对地增加了用于滤波的第一电容C1，第一电容C1的一端连接转换电阻R0的另一端，第一电容C1的另一端接地，通过第一电容C1的滤波作用可有效减小第一参考电压V_LVC的波动，最终可以降低输出至恒流源模块40的第三参考电压的波动，从而减小恒流源输出的纹波。
进一步地，请一并参阅图7和图8，所述调制模块20包括信号接收单元201 和调制单元202，所述信号接收单元201连接调制单元202，所述调制单元202还连接所述分压单元104和滤波模块30，由信号接收单元201(如图7所示)接收外部输入的PWM信号，由于外部输入PWM信号的电压与驱动系统内部的电源电压可能不匹配，因此通过信号接收单元201对PWM信号进行电平移位处理后再输出至调制单元202，而通过调制单元202接收经过电平移位处理后的PWM信号以及分压单元104输出的第一参考电压V_LVC，对第一参考电压V_LVC进行调制，从而生成占空比与PWM信号相同，幅度信号与第一参考电压V_LVC相同的第二参考电压V_ALG至滤波模块30。
具体来说，所述信号接收单元201包括移位器、第一反相器A21和第二反相器A22，所述调制单元202包括第一开关S1和第二开关S2；所述移位器的一端连接PWM信号输入端，所述移位器的另一端连接第一反相器A21的输入端，所述第一反相器A21的输出端连接第二开关S2的控制端和第二反相器A22的输入端；所述第二反相器A22的输出端连接第一开关S1的控制端；所述第一开关S1的两个连接端分别连接第一运算放大器A1的输出端和滤波模块30，所述第二开关S2的两个连接端分别连接滤波模块30和地。外部输入的PWM信号经过移位器进行电平移位后，经两级反相器产生同相信号PWM_P和PWM_N用于分别驱动第一开关S1和第二开关S2，通过控制第一开关S1和第二开关S2对第一参考电压V_LVC进行调制，从而生成与PWM信号占空比相同，与第一参考电压V_LVC幅度相同的第二参考电压V_ALG，经过后续滤波处理后输出至恒流源模块40，以控制恒流源的输出电流实现调光，这样当PWM信号的占空比改变时，系统的输入功率随之线性变化；而保持同样的PWM占空比输入时，当输入市电电压变化时，系统的输入功率基本保持不变，有效减少压闪现象，提高整体照明效果。
进一步地，请一并参阅图9，所述滤波模块30为一阶RC滤波电路，其包括第三电阻R3和第二电容C2，所述恒流源模块40包括第二运算放大器A2和高压MOS管M0；所述第三电阻R3的一端连接第一开关S1和第二开关S2的连接端，所述第三电阻R3的另一端连接第二运算放大器A2的同相输入端、还通过第二电容C2接地；所述第二运算放大器A2的反相输入端连接高压MOS管M0的源极、通过采样电阻Rs接地，所述第二运算放大器A2的输出端连接高压MOS 管M0的栅极；所述高压MOS管M0的漏极连接待调光的LED灯串11的负极。
通过由第三电阻R3和第二电容C2构成的一阶RC滤波电路对第二参考电压V_ALG滤波后，输出第三参考电压VREF，而该直流参考电压信号具有以下特性，当输入线电压不变时，第三参考电压VREF跟随PWM占空比变化而变化，可以实现输入功率随PWM占空比线性变化，达到调光目的；当PWM占空比不变时，第三参考电压VREF随着输入线电压的上升而下降，可以实现输入功率不随输入线电压改变，保持输入功率的恒定，以提高照明效果，具体如图10所示，图10中的(a)表示线电压，图10中的(b)表示根据线电压大小输出端的具有补偿信息的第一参考电压V_LVC，图10中的(c)表示经过信号调制后输出的同事具有补偿信息和PWM占空比信息的第二参考电压V_ALG，从图中可看出，第一参考电压根据输入线电压大小进行了相应的补偿，本实施例中，当线电压小于等于阈值电压Vth时，第一参考电压输出为恒定值，而当大于阈值电压Vth时，此时第一参考电压不再为恒定的值，而是随着线电压的升高而降低，随着线电压的减低而升高，达到电压补偿的目的，从而在恒流驱动中，实现功率的恒定，而经过调制后输出端的第二参考电压，不仅具有第一参考电压的幅度信息，同时还具有PWM信号的占空比信息，在正常调光操作时，是的输入功率岁PWM占空比线性变换，从而达到调光目的。
相应地，本发明还提供一种LED驱动装置的恒功率调光方法，如图11所示，所述LED驱动装置的恒功率调光方法包括如下步骤：
S100、由线电压补偿模块检测线电压的变化，并根据当前线电压大小输出具有补偿信息的第一参考电压；
S200、调制模块根据外部输入的PWM信号对所述第一参考电压进行调制，输出同时具有补偿信息和PWM占空比信息的第二参考电压至滤波模块；
S300、经滤波模块进行滤波后输出第三参考电压至恒流源模块，控制恒流源模块输出恒流以驱动LED负载工作。
本发明还相应提供一种LED驱动装置的恒功率调光电路，由于上文已对所述恒功率调光电路进行了详细介绍，此处不再详述。
综上所述，本发明提供的LED驱动装置及其恒功率调光电路、调光方法中，所述LED驱动装置的恒功率调光电路包括线电压补偿模块、调制模块、滤波模 块和恒流源模块；由线电压补偿模块检测线电压的变化，并根据当前线电压大小输出具有补偿信息的第一参考电压；调制模块根据外部输入的PWM信号对所述第一参考电压进行调制，输出同时具有补偿信息和PWM占空比信息的第二参考电压至滤波模块；经滤波模块进行滤波后输出第三参考电压至恒流源模块，控制恒流源模块输出恒流以驱动LED负载工作，通过输出同时具有线电压补偿信息和PWM信号占空比信息的电压来控制恒流源电路，可实现在PWM信号的占空比不变而市电输入电压变化时，系统的输入功率保持恒定，减少压闪现象。
可以理解的是，对本领域普通技术人员来说，可以根据本发明的技术方案及其发明构思加以等同替换或改变，而所有这些改变或替换都应属于本发明所附的权利要求的保护范围。

Claims (10)

  1. 一种LED驱动装置的恒功率调光电路，其特征在于，包括线电压补偿模块、调制模块、滤波模块和恒流源模块；由线电压补偿模块检测线电压的变化，并根据当前线电压大小输出具有补偿信息的第一参考电压；调制模块根据外部输入的PWM信号对所述第一参考电压进行调制，输出同时具有补偿信息和PWM占空比信息的第二参考电压至滤波模块；经滤波模块进行滤波后输出第三参考电压至恒流源模块，控制恒流源模块输出恒流以驱动LED负载工作。
  2. 根据权利要求1所述的LED驱动装置的恒功率调光电路，其特征在于，所述线电压补偿模块具体用于，当当前线电压小于等于阈值电压时，输出按预设规律变化的第一参考电压；当当前线电压大于阈值电压时，根据线电压的大小输出具有补偿信息的第一参考电压。
  3. 根据权利要求1所述的LED驱动装置的恒功率调光电路，其特征在于，所述调制模块具体用于根据外部输入的PWM信号对所述第一参考电压进行调制后输出第二参考电压，使第二参考电压的占空比与PWM信号相同，第二参考电压的幅值与第一参考电压相同。
  4. 根据权利要求1所述的LED驱动装置的恒功率调光电路，其特征在于，所述线电压补偿模块包括电流源、电压源、转换单元、第一电流镜单元、第二电流镜单元和分压单元；输入线电压通过转换单元转换为第一电流后输出至第一电流镜单元，经第一电流镜单元进行第一预设倍数镜像处理后得到第二电流，所述第二电流和电流源输出的第三电流进行减法运算后得到的第四电流输出至第二电流镜单元，经第二电流镜单元进行第二预设倍数镜像处理后得到第五电流，所述电压源输出参考电压至分压单元，根据所述第五电流控制所述参考电压经分压单元分压后输出的第一参考电压的大小，得到具有补偿信息的第一参考电压。
  5. 根据权利要求1所述的LED驱动装置的恒功率调光电路，其特征在于，所述调制模块包括信号接收单元和调制单元，由信号接收单元接收外部输入的PWM信号，对其进行电平移位处理后输出至调制单元，由所述调制单元根据经电平移位处理后的PWM信号对所述第一参考电压进行调制，输出第二参考电压，使第二参考电压的占空比与PWM信号相同，第二参考电压的幅值与第一参考电压相同。
  6. 根据权利要求4所述的LED驱动装置的恒功率调光电路，其特征在于， 所述转换单元包括转换电阻，所述第一电流镜单元包括第一MOS管、第二MOS管、第三MOS管、第四MOS管、第五MOS管、第六MOS管、第七MOS管和第八MOS管；所述转换电阻的一端连接线电压输出端，所述转换电阻的另一端连接第一MOS管的漏极、第一MOS管的栅极和第二MOS管的栅极；所述第一MOS管的源极接地，所述第一MOS管的衬底连接第三MOS管的漏极、第三MOS管的栅极和第四MOS管的栅极；所述第二MOS管的漏极连接第七MOS管的漏极、第七MOS管的栅极和第八MOS管的栅极，所述第二MOS管的源极接地，所述第二MOS管的衬底连接第四MOS管的漏极；所述第三MOS管的源极和衬底均接地；所述第四MOS管的源极和衬底均接地；所述第五MOS管的源极和衬底连接VDD供电端，所述第五MOS管的栅极连接第五MOS管的漏极、第六MOS管的栅极和第七MOS管的衬底；所述第六MOS管的源极和衬底连接VDD供电端，所述第六MOS管的漏极连接第八MOS管的衬底；所述第七MOS管的源极连接VDD供电端；所述第八MOS管的源极连接VDD供电端，所述第八MOS管的漏极连接电流源的一端和第二电流镜单元，电流源的另一端接地。
  7. 根据权利要求6所述的LED驱动装置的恒功率调光电路，其特征在于，所述第二电流镜单元包括第九MOS管和第十MOS管，所述第九MOS管的漏极连接第八MOS管的漏极、第九MOS管的栅极和第十MOS管的栅极，所述第九MOS管的源极和衬底均接地；所述第十MOS管的漏极连接所述分压单元，所述第十MOS管的源极和衬底均接地。
  8. 根据权利要求7所述的LED驱动装置的恒功率调光电路，其特征在于，所述分压单元包括第一电阻、第二电阻和第一运算放大器；所述第一电阻的一端连接电压源的正极，所述第一电阻的另一端连接第十MOS管的漏极、第一运算放大器的同相输入端、还通过第二电阻接地；所述第一运算放大器的反相输入端连接第一运算放大器的输出端和调制模块。
  9. 一种LED驱动装置的恒功率调光方法，其特征在于，包括如下步骤：
    A、由线电压补偿模块检测线电压的变化，并根据当前线电压大小输出具有补偿信息的第一参考电压；
    B、调制模块根据外部输入的PWM信号对所述第一参考电压进行调制，输出同时具有补偿信息和PWM占空比信息的第二参考电压至滤波模块；
    C、经滤波模块进行滤波后输出第三参考电压至恒流源模块，控制恒流源模块输出恒流以驱动LED负载工作。
  10. 一种LED驱动装置，包括LED灯串、用于对输入交流电进行整流的整流模块和对LED灯串电流进行采样的采样电阻，其特征在于，所述LED驱动装置还包括如权利要求1-8任意一项所述的恒功率调光电路，所述整流模块的输入端连接交流电，所述整流模块的输出端连接恒功率调光电路和LED灯串，所述恒功率调光电路还通过采样电阻接地。
PCT/CN2018/086102 2017-05-19 2018-05-09 Led驱动装置及其恒功率调光电路、调光方法 Ceased WO2018210166A1 (zh)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US16/615,129 US10721799B2 (en) 2017-05-19 2018-05-09 LED driving device, constant-power dimming circuit and dimming method thereof
EP18803237.9A EP3627971A4 (en) 2017-05-19 2018-05-09 LED DRIVING DEVICE AND CONSTANT POWER GRADING CIRCUIT AND GRADING METHOD THEREOF

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201710357761.6A CN107071982B (zh) 2017-05-19 2017-05-19 Led驱动装置及其恒功率调光电路、调光方法
CN201710357761.6 2017-05-19

Publications (1)

Publication Number Publication Date
WO2018210166A1 true WO2018210166A1 (zh) 2018-11-22

Family

ID=59609490

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2018/086102 Ceased WO2018210166A1 (zh) 2017-05-19 2018-05-09 Led驱动装置及其恒功率调光电路、调光方法

Country Status (4)

Country Link
US (1) US10721799B2 (zh)
EP (1) EP3627971A4 (zh)
CN (1) CN107071982B (zh)
WO (1) WO2018210166A1 (zh)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109819568A (zh) * 2019-03-29 2019-05-28 广州腾龙电子塑胶科技有限公司 一种基于两线的多电平对应多通道信号传输系统
CN112839407A (zh) * 2019-11-07 2021-05-25 华润微集成电路(无锡)有限公司 线性led驱动系统及驱动方法
CN113891521A (zh) * 2021-11-05 2022-01-04 深圳市角度控光智能照明技术有限公司 一种pwm斩波调光冗余电路及其斩波调光方法
CN114285314A (zh) * 2021-12-30 2022-04-05 吉林大学 一种基于单片机控制的高稳定度脉冲电流源
CN117369583A (zh) * 2023-10-26 2024-01-09 深圳木芯科技有限公司 恒定功率控制电路及电子设备
CN117395831A (zh) * 2023-10-30 2024-01-12 中国科学院长春光学精密机械与物理研究所 一种led驱动调光电路及控制方法

Families Citing this family (52)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107071982B (zh) 2017-05-19 2018-08-14 深圳市晟碟半导体有限公司 Led驱动装置及其恒功率调光电路、调光方法
CN107580395B (zh) * 2017-09-30 2024-07-09 富满微电子集团股份有限公司 功率控制装置、方法及系统
CN107678481B (zh) * 2017-10-09 2018-11-20 江苏先云信息技术有限公司 无人驾驶光电软驱动恒流电路、集成电路与控制系统
CN108601144A (zh) * 2017-10-09 2018-09-28 东莞市翔实信息科技有限公司 无人驾驶电光驱动集成电路
CN108617060B (zh) * 2018-06-27 2024-04-05 深圳市明微电子股份有限公司 一种宽输入电压的恒流明驱动电路及装置
CN108712801B (zh) * 2018-06-27 2023-09-29 深圳市明微电子股份有限公司 一种宽输入电压的恒功率驱动电路及装置
CN108925008A (zh) * 2018-08-14 2018-11-30 上海艾为电子技术股份有限公司 驱动方法、驱动电路、补偿电路及调光系统
CN108922472A (zh) * 2018-08-14 2018-11-30 上海艾为电子技术股份有限公司 驱动方法、驱动电路、补偿电路及调光系统
CN109152157B (zh) * 2018-10-26 2024-07-19 深圳市晟碟半导体有限公司 一种双电压led驱动电路、驱动装置及驱动方法
CN109195273B (zh) * 2018-10-26 2021-03-30 深圳市晟碟半导体有限公司 一种led灯具的恒功率控制装置及恒功率控制方法
CN109309993B (zh) * 2018-11-16 2024-02-27 苏州中储普华电力科技有限公司 用于智能照明的回路调光电路
CN109743811B (zh) * 2018-12-24 2025-02-25 欧普照明股份有限公司 一种电流控制电路
CN109640446B (zh) * 2018-12-24 2025-04-22 欧普照明股份有限公司 一种ic芯片、驱动电路及灯具控制系统
CN110035584B (zh) * 2019-04-28 2024-03-19 深圳市晟碟半导体有限公司 一种提高调光精度的led调光电路、调光装置及调光方法
CN112020169B (zh) * 2019-05-13 2023-05-09 通嘉科技股份有限公司 可接收脉宽调变信号与直流信号的调光控制器及调光方法
CN110177410A (zh) * 2019-05-24 2019-08-27 深圳市晟碟半导体有限公司 一种led调光电路、调光装置及调光方法
CN110545603B (zh) * 2019-09-17 2024-09-03 宁波欧陆克电器有限公司 一种led灯的功率补偿电路
CN112654108B (zh) * 2019-09-26 2023-06-06 上海晶丰明源半导体股份有限公司 调光控制电路、控制芯片、电源转换装置以及调光方法
CN110740544A (zh) * 2019-12-09 2020-01-31 深圳市晟碟半导体有限公司 一种降低可控硅调光频闪的调光电路、装置及调光方法
CN110943601B (zh) * 2019-12-18 2024-11-26 西安航天民芯科技有限公司 一种用于恒定导通时间控制模式开关电源的恒定频率电路
CN111083854B (zh) * 2020-01-10 2021-07-27 中科芯集成电路有限公司 一种led显示屏补偿电路及其方法
CN111239465B (zh) * 2020-01-16 2023-05-23 昂宝电子（上海）有限公司 线电压检测电路、系统及方法
CN111800903B (zh) * 2020-08-05 2024-09-20 深圳市明微电子股份有限公司 Led恒流驱动电路及led驱动系统
CN112033901A (zh) * 2020-08-10 2020-12-04 珠海格力电器股份有限公司 一种光源零点补偿装置、传感器及其光源零点补偿方法
CN111741569A (zh) * 2020-08-13 2020-10-02 深圳市比尔达科技有限公司 Led开关电源控制功率恒定的电路及方法
CN112104229B (zh) * 2020-09-25 2021-10-12 深圳南云微电子有限公司 一种buck控制电路、控制方法和基准产生电路
CN112188674A (zh) * 2020-10-19 2021-01-05 美芯晟科技（北京）有限公司 一种无频闪的pwm调光控制方法及电路
CN112188676B (zh) * 2020-10-29 2025-08-12 华域视觉科技(上海)有限公司 Led光源呼吸效果调节电路及led光源驱动电路
CN112135390B (zh) * 2020-11-24 2021-02-02 上海芯龙半导体技术股份有限公司南京分公司 调光电路及电源芯片
CN112291880A (zh) * 2020-11-26 2021-01-29 众智学府信息技术有限公司 一种节能型led路灯智能控制系统
CN114698187B (zh) * 2020-12-30 2025-01-24 华润微集成电路(无锡)有限公司 一种led驱动方法
CN114980418B (zh) * 2021-02-18 2025-08-01 华润微集成电路(无锡)有限公司 实现led调光的电路结构
CN113015290B (zh) * 2021-03-31 2025-03-07 上海新进芯微电子有限公司 一种线性led驱动电路
CN113179565B (zh) * 2021-05-06 2024-01-12 上海奥简微电子科技有限公司 Led可控硅调光深度补偿电路及led照明装置
CN113825279B (zh) * 2021-11-25 2022-03-04 上海南麟电子股份有限公司 Led驱动系统及其驱动方法
CN115175405A (zh) * 2022-06-14 2022-10-11 浙江凯耀照明有限责任公司 一种基于mcu控制在开关电源原边实现恒功率的控制电路
CN116234091B (zh) * 2022-11-16 2025-06-24 深圳市曼多拉科技有限公司 一种模拟自然光的养殖灯控电路
CN116149412B (zh) * 2022-11-30 2024-12-20 天津津航计算技术研究所 一种恒流源功率驱动电路
TWI854390B (zh) * 2022-12-09 2024-09-01 穩脈科技股份有限公司 輸出過濾之電壓源電路
CN115802537B (zh) * 2022-12-16 2026-04-28 苏州欧普照明有限公司 可调光驱动电路
CN116321586B (zh) * 2023-02-21 2024-08-06 鲁格照明科技有限公司 一种led恒流载波调光装置
CN116056281B (zh) * 2023-03-07 2023-11-28 华南理工大学 一种驱动方式可选的led调光电路
JP2024140970A (ja) * 2023-03-28 2024-10-10 ローム株式会社 定電流回路、タイマー回路、ワンショットマルチバイブレータ回路、半導体集積回路
CN116453471B (zh) * 2023-04-12 2025-11-28 昂宝集成电路股份有限公司 用于mini LED背光源的通道电流控制设备及方法
CN116261238B (zh) * 2023-05-15 2023-07-21 上海杰茗科技有限公司 一种ToF光源驱动电路及电子设备
CN116436297B (zh) * 2023-06-09 2023-11-10 华中科技大学 一种双电流环控制的开关线性混合功率变换系统
TWI879009B (zh) * 2023-08-07 2025-04-01 德禮實業有限公司 燈具調光控制系統及燈具自動判定調光範圍之方法
CN118574263A (zh) * 2024-06-20 2024-08-30 无锡市益明光电有限公司 一种宽负载led驱动电源负载调整率优化电路
CN119136363B (zh) * 2024-10-22 2025-03-28 上海芯北电子科技有限公司 一种发光二极管的混合调光系统
CN119545600B (zh) * 2025-01-21 2025-06-20 钰泰半导体股份有限公司 Led驱动电路
CN120343766A (zh) * 2025-04-28 2025-07-18 苏州密卡特诺精密机械有限公司 一种用于光影测试场景中的led灯亮度控制电路
CN120111756B (zh) * 2025-05-07 2025-07-11 珠海市路明莱特照明科技有限公司 一种组合式接线盒光调节方法及存储介质

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103108470A (zh) * 2013-02-06 2013-05-15 深圳市芯飞凌半导体有限公司 动态线性控制led驱动电路
CN103607810A (zh) * 2013-10-31 2014-02-26 汤志新 一种led照明设备的控制电路
CN203801121U (zh) * 2014-03-21 2014-08-27 深圳市梓晶微科技有限公司 一种用于led驱动的线电压补偿电路
US9125273B2 (en) * 2012-11-29 2015-09-01 Beyond Innovation Technology Co., Ltd. Load driving apparatus relating to light-emitting-diodes
CN105657903A (zh) * 2016-03-10 2016-06-08 矽力杰半导体技术(杭州)有限公司 一种用于led的混合调光电路及混合调光方法
CN107071982A (zh) * 2017-05-19 2017-08-18 深圳市晟碟半导体有限公司 Led驱动装置及其恒功率调光电路、调光方法
CN206775787U (zh) * 2017-05-19 2017-12-19 深圳市晟碟半导体有限公司 Led驱动装置及其恒功率调光电路

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8319445B2 (en) * 2008-04-15 2012-11-27 Boca Flasher, Inc. Modified dimming LED driver
US8686668B2 (en) * 2009-10-26 2014-04-01 Koninklijke Philips N.V. Current offset circuits for phase-cut power control
CN101711081B (zh) * 2009-12-21 2013-04-03 Bcd半导体制造有限公司 Led驱动电路
US9183788B2 (en) * 2013-05-20 2015-11-10 Shenzhen China Star Optoelectronics Technology Co., Ltd Backlight driving circuit, LCD device, and method for driving the backlight driving circuit
CN104661392B (zh) * 2013-11-25 2017-08-25 上海莱托思电子科技有限公司 一种led开关恒流驱动电路
CN103763817B (zh) * 2013-12-30 2016-06-01 深圳市晟碟绿色集成科技有限公司 一种线电压补偿ac led驱动装置

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9125273B2 (en) * 2012-11-29 2015-09-01 Beyond Innovation Technology Co., Ltd. Load driving apparatus relating to light-emitting-diodes
CN103108470A (zh) * 2013-02-06 2013-05-15 深圳市芯飞凌半导体有限公司 动态线性控制led驱动电路
CN103607810A (zh) * 2013-10-31 2014-02-26 汤志新 一种led照明设备的控制电路
CN203801121U (zh) * 2014-03-21 2014-08-27 深圳市梓晶微科技有限公司 一种用于led驱动的线电压补偿电路
CN105657903A (zh) * 2016-03-10 2016-06-08 矽力杰半导体技术(杭州)有限公司 一种用于led的混合调光电路及混合调光方法
CN107071982A (zh) * 2017-05-19 2017-08-18 深圳市晟碟半导体有限公司 Led驱动装置及其恒功率调光电路、调光方法
CN206775787U (zh) * 2017-05-19 2017-12-19 深圳市晟碟半导体有限公司 Led驱动装置及其恒功率调光电路

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP3627971A4 *

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109819568A (zh) * 2019-03-29 2019-05-28 广州腾龙电子塑胶科技有限公司 一种基于两线的多电平对应多通道信号传输系统
CN109819568B (zh) * 2019-03-29 2024-02-13 广州腾龙健康实业股份有限公司 一种基于两线的多电平对应多通道信号传输系统
CN112839407A (zh) * 2019-11-07 2021-05-25 华润微集成电路(无锡)有限公司 线性led驱动系统及驱动方法
CN112839407B (zh) * 2019-11-07 2023-05-26 华润微集成电路(无锡)有限公司 线性led驱动系统及驱动方法
CN113891521A (zh) * 2021-11-05 2022-01-04 深圳市角度控光智能照明技术有限公司 一种pwm斩波调光冗余电路及其斩波调光方法
CN113891521B (zh) * 2021-11-05 2023-09-19 深圳市角度控光智能照明技术有限公司 一种pwm斩波调光冗余电路及其斩波调光方法
CN114285314A (zh) * 2021-12-30 2022-04-05 吉林大学 一种基于单片机控制的高稳定度脉冲电流源
CN114285314B (zh) * 2021-12-30 2023-09-12 吉林大学 一种基于单片机控制的高稳定度脉冲电流源
CN117369583A (zh) * 2023-10-26 2024-01-09 深圳木芯科技有限公司 恒定功率控制电路及电子设备
CN117395831A (zh) * 2023-10-30 2024-01-12 中国科学院长春光学精密机械与物理研究所 一种led驱动调光电路及控制方法
CN117395831B (zh) * 2023-10-30 2024-05-07 中国科学院长春光学精密机械与物理研究所 一种led驱动调光电路及控制方法

Also Published As

Publication number Publication date
CN107071982B (zh) 2018-08-14
US10721799B2 (en) 2020-07-21
EP3627971A4 (en) 2020-05-06
EP3627971A1 (en) 2020-03-25
US20200128645A1 (en) 2020-04-23
CN107071982A (zh) 2017-08-18

Similar Documents

Publication Publication Date Title
WO2018210166A1 (zh) Led驱动装置及其恒功率调光电路、调光方法
CN109392218B (zh) 调光装置及电力变换装置
TWI595735B (zh) 可降低電流漣波之電流調節電路及降低電流漣波的方法
US8736185B2 (en) SCR dimming circuit and method
WO2018157480A1 (zh) 一种恒功率正弦线性led驱动电路及led驱动装置
US10140931B2 (en) Shadow mask assemblies and reusing methods of shadow mask assemblies thereof
US9532421B2 (en) LED driving device and control method for LED driving device
US20110115391A1 (en) Led lamp and led lamp module
WO2019196695A1 (zh) 一种led调光控制电路
TWI736367B (zh) 具有高功率因數之升壓轉換器
CN206775787U (zh) Led驱动装置及其恒功率调光电路
CN103648202A (zh) 有源功率因数校正控制电路、芯片及led驱动电路
US10537000B2 (en) Controller, light source driving circuit and method for controlling light source module
US7986110B2 (en) Light source driving device
US11297702B2 (en) Dimmer interface circuit and buffer stage circuit thereof
CN108075655B (zh) 电源转换装置
US10470261B2 (en) Method of generating stable direct current signal, silicon controlled switch dimming method and device
CN111200892B (zh) 一种led控制装置、电路及其控制方法
CN118737014B (zh) 一种光感电流自动调节的增益电路、方法，以及显示面板
CN211509379U (zh) 一种led控制装置、电路
CN205142005U (zh) Pwm调压电路及恒压源电路
CN108712801B (zh) 一种宽输入电压的恒功率驱动电路及装置
CN214125566U (zh) Led调光电路、led驱动系统及电子设备
CN103889121A (zh) 一种纹波电流抑制电路
CN107734761B (zh) 一种超高度集成的led调光电路

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18803237

Country of ref document: EP

Kind code of ref document: A1

DPE2 Request for preliminary examination filed before expiration of 19th month from priority date (pct application filed from 20040101)
NENP Non-entry into the national phase

Ref country code: DE

WWE Wipo information: entry into national phase

Ref document number: 2018803237

Country of ref document: EP

ENP Entry into the national phase

Ref document number: 2018803237

Country of ref document: EP

Effective date: 20191219