WO2014079076A1 - Led调光驱动模块、背光模组及液晶显示装置 - Google Patents

Led调光驱动模块、背光模组及液晶显示装置 Download PDF

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Publication number
WO2014079076A1
WO2014079076A1 PCT/CN2012/085338 CN2012085338W WO2014079076A1 WO 2014079076 A1 WO2014079076 A1 WO 2014079076A1 CN 2012085338 W CN2012085338 W CN 2012085338W WO 2014079076 A1 WO2014079076 A1 WO 2014079076A1
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Prior art keywords
capacitor
duty ratio
unit
current
control switch
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PCT/CN2012/085338
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English (en)
French (fr)
Inventor
黎飞
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TCL China Star Optoelectronics Technology Co Ltd
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Shenzhen China Star Optoelectronics Technology Co Ltd
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Priority to US13/701,868 priority Critical patent/US8957589B2/en
Priority to DE112012007036.4T priority patent/DE112012007036B4/de
Publication of WO2014079076A1 publication Critical patent/WO2014079076A1/zh
Anticipated expiration legal-status Critical
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    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/10Controlling the intensity of the light

Definitions

  • the invention relates to the field of LED dimming, in particular to an LED dimming driving module, a backlight module and a liquid crystal display device.
  • LED Light Emitting Diode, light-emitting diodes
  • FIG. 1 is a schematic circuit diagram of a prior art LED dimming driving circuit.
  • the LED dimming drive circuit includes a comparator A, a current source S and a capacitor C. One end of the capacitor C is connected to the first input terminal of the comparator A, and the other end is grounded. Current source S is coupled to the first input of comparator A. The second input of comparator A inputs a threshold voltage V.
  • the LED dimming drive circuit will respond to the pulse width modulation signal P.
  • the current source S When the pulse width modulation signal P is at a high level, the current source S outputs a current to charge the capacitor C. When the voltage on the capacitor C climbs above the threshold voltage V, The output of comparator A outputs a high level for adjusting the brightness of the LED backlight.
  • the duty ratio of the pulse width modulation signal P is small and the charging time of the capacitor C is short, the voltage on the capacitor C will not reach the threshold voltage V, and the pulse width modulation signal P passes through multiple After the high level, the voltage on the capacitor C climbs above the threshold voltage V, the comparator A outputs a high level, and the LED backlight illuminates. During the illumination of the LED backlight, the charging voltage of the capacitor C climbs to the threshold voltage V. The long time required causes the human eye to see flickering, which seriously affects the quality of the light source.
  • the technical problem to be solved by the present invention is to provide an LED dimming driving module, a backlight module and a liquid crystal display device, which can avoid flickering.
  • an LED dimming driving module which includes a duty ratio detecting unit, a current output unit, a comparator, and a capacitor unit.
  • the first input of the comparator is connected to the capacitor unit, and the second input of the comparator is input with a preset threshold voltage.
  • the current output unit is connected to the capacitor unit to charge the capacitor unit.
  • the duty ratio detecting unit is configured to receive the pulse width modulation signal of the external input and detect the duty ratio of the pulse width modulation signal. When the duty ratio detecting unit detects that the duty ratio is less than a predetermined threshold, the current output unit increases the output current or the capacitor unit reduces the supplied capacitance to reduce the time when the voltage of the capacitor unit climbs to the preset threshold voltage.
  • the current output unit outputs a first current when the duty ratio detecting unit detects that the duty ratio is less than a predetermined threshold, and the current output unit outputs the second current when the duty ratio detecting unit detects that the duty ratio is greater than a predetermined threshold.
  • the current value of the second current is smaller than the current value of the first current.
  • the capacitor unit provides a first capacitor when the duty ratio detecting unit detects that the duty ratio is less than a predetermined threshold, and the capacitor unit provides the second capacitor when the duty ratio detecting unit detects that the duty ratio is greater than a predetermined threshold.
  • the capacitance of the first capacitor is less than the capacitance of the second capacitor.
  • the current output unit includes a first control switch, a first current source, and a second current source, and the capacitor unit includes a first capacitor.
  • the duty ratio detecting unit sends the first control signal to the first control switch when detecting that the duty ratio is less than a predetermined threshold, and sends the second control signal to the first control switch when detecting that the duty ratio is greater than a predetermined threshold.
  • the first control switch includes a first end, a second end, a third end, and a fourth end, the first end is connected to the duty ratio detecting unit, and when the first end acquires the first control signal, the fourth end and the second end Connecting, when the first end acquires the second control signal, the fourth end is connected to the third end; the first current source is connected to the second end of the first control switch to output the first current; and the second current source is connected to the first control switch The third end outputs a second current; one end of the first capacitor is connected to the fourth end of the first control switch and the first input of the comparator, and the other end of the first capacitor is grounded.
  • the current output unit includes a third current source, and the capacitor unit includes a second control switch, a second capacitor, and a third capacitor, wherein the duty ratio detecting unit transmits the first control signal when detecting that the duty ratio is less than a predetermined threshold Up to a second control switch, when detecting that the duty ratio is greater than a predetermined threshold, transmitting a second control signal to the second control switch;
  • the second control switch includes a first end, a second end, a third end, and a fourth end, One end is connected to the duty ratio detecting unit, and when the first end acquires the first control signal, the fourth end is connected to the second end, and when the first end acquires the second control signal, the fourth end is connected to the third end;
  • One end of the two capacitor is connected to the second end of the second control switch, the other end of the second capacitor is grounded, the second capacitor provides the first capacitor;
  • one end of the third capacitor is connected to the third end of the second control switch, and the third capacitor is another One end is grounded, the third
  • the duty ratio detecting unit, the current output unit, and the comparator are packaged in one body.
  • the present invention also adopts a technical solution to provide a backlight module, which includes an LED lamp and an LED dimming driving module.
  • the LED dimming driving module includes a duty ratio detecting unit, a current output unit, a comparator, and a capacitor unit.
  • the first input of the comparator is connected to the capacitor unit, and the second input of the comparator is input with a preset threshold voltage.
  • the current output unit is connected to the capacitor unit to charge the capacitor unit.
  • the duty ratio detecting unit is configured to receive the pulse width modulation signal of the external input and detect the duty ratio of the pulse width modulation signal.
  • the current output unit increases the output current or the capacitor unit reduces the supplied capacitance to reduce the time when the voltage of the capacitor unit climbs to the preset threshold voltage, the comparator The output of the output outputs a high level or a low level to adjust the brightness of the LED light.
  • the current output unit outputs a first current when the duty ratio detecting unit detects that the duty ratio is less than a predetermined threshold, and the current output unit outputs the second current when the duty ratio detecting unit detects that the duty ratio is greater than a predetermined threshold.
  • the current value of the second current is smaller than the current value of the first current.
  • the capacitor unit provides a first capacitor when the duty ratio detecting unit detects that the duty ratio is less than a predetermined threshold, and the capacitor unit provides the second capacitor when the duty ratio detecting unit detects that the duty ratio is greater than a predetermined threshold.
  • the capacitance of the first capacitor is less than the capacitance of the second capacitor.
  • the current output unit includes a first control switch, a first current source, and a second current source, and the capacitor unit includes a first capacitor.
  • the duty ratio detecting unit sends the first control signal to the first control switch when detecting that the duty ratio is less than a predetermined threshold, and sends the second control signal to the first control switch when detecting that the duty ratio is greater than a predetermined threshold.
  • the first control switch includes a first end, a second end, a third end, and a fourth end, the first end is connected to the duty ratio detecting unit, and when the first end acquires the first control signal, the fourth end and the second end Connecting, when the first end acquires the second control signal, the fourth end is connected to the third end; the first current source is connected to the second end of the first control switch to output the first current; and the second current source is connected to the first control switch The third end outputs a second current; one end of the first capacitor is connected to the fourth end of the first control switch and the first input of the comparator, and the other end of the first capacitor is grounded.
  • the current output unit includes a third current source, and the capacitor unit includes a second control switch, a second capacitor, and a third capacitor, wherein the duty ratio detecting unit transmits the first control signal when detecting that the duty ratio is less than a predetermined threshold Up to a second control switch, when detecting that the duty ratio is greater than a predetermined threshold, transmitting a second control signal to the second control switch;
  • the second control switch includes a first end, a second end, a third end, and a fourth end, One end is connected to the duty ratio detecting unit, and when the first end acquires the first control signal, the fourth end is connected to the second end, and when the first end acquires the second control signal, the fourth end is connected to the third end;
  • One end of the two capacitor is connected to the second end of the second control switch, the other end of the second capacitor is grounded, the second capacitor provides the first capacitor;
  • one end of the third capacitor is connected to the third end of the second control switch, and the third capacitor is another One end is grounded, the third
  • the duty ratio detecting unit, the current output unit, and the comparator are packaged in one body.
  • a liquid crystal display device including a backlight module, and the backlight module includes an LED lamp and an LED dimming driving module.
  • the LED dimming driving module includes a duty ratio detecting unit, a current output unit, a comparator, and a capacitor unit.
  • the first input of the comparator is connected to the capacitor unit, and the second input of the comparator is input with a preset threshold voltage.
  • the current output unit is connected to the capacitor unit to charge the capacitor unit.
  • the duty ratio detecting unit is configured to receive the pulse width modulation signal of the external input and detect the duty ratio of the pulse width modulation signal.
  • the current output unit increases the output current or the capacitor unit reduces the supplied capacitance to reduce the time when the voltage of the capacitor unit climbs to the preset threshold voltage, the comparator The output of the output outputs a high level or a low level to adjust the brightness of the LED light.
  • the current output unit outputs a first current when the duty ratio detecting unit detects that the duty ratio is less than a predetermined threshold, and the current output unit outputs the second current when the duty ratio detecting unit detects that the duty ratio is greater than a predetermined threshold.
  • the current value of the second current is smaller than the current value of the first current.
  • the capacitor unit provides a first capacitor when the duty ratio detecting unit detects that the duty ratio is less than a predetermined threshold, and the capacitor unit provides the second capacitor when the duty ratio detecting unit detects that the duty ratio is greater than a predetermined threshold.
  • the capacitance of the first capacitor is less than the capacitance of the second capacitor.
  • the current output unit includes a first control switch, a first current source, and a second current source, and the capacitor unit includes a first capacitor.
  • the duty ratio detecting unit sends the first control signal to the first control switch when detecting that the duty ratio is less than a predetermined threshold, and sends the second control signal to the first control switch when detecting that the duty ratio is greater than a predetermined threshold.
  • the first control switch includes a first end, a second end, a third end, and a fourth end, the first end is connected to the duty ratio detecting unit, and when the first end acquires the first control signal, the fourth end and the second end Connecting, when the first end acquires the second control signal, the fourth end is connected to the third end; the first current source is connected to the second end of the first control switch to output the first current; and the second current source is connected to the first control switch The third end outputs a second current; one end of the first capacitor is connected to the fourth end of the first control switch and the first input of the comparator, and the other end of the first capacitor is grounded.
  • the current output unit includes a third current source, and the capacitor unit includes a second control switch, a second capacitor, and a third capacitor, wherein the duty ratio detecting unit transmits the first control signal when detecting that the duty ratio is less than a predetermined threshold Up to a second control switch, when detecting that the duty ratio is greater than a predetermined threshold, transmitting a second control signal to the second control switch;
  • the second control switch includes a first end, a second end, a third end, and a fourth end, One end is connected to the duty ratio detecting unit, and when the first end acquires the first control signal, the fourth end is connected to the second end, and when the first end acquires the second control signal, the fourth end is connected to the third end;
  • One end of the two capacitor is connected to the second end of the second control switch, the other end of the second capacitor is grounded, the second capacitor provides the first capacitor;
  • one end of the third capacitor is connected to the third end of the second control switch, and the third capacitor is another One end is grounded, the third
  • the duty ratio detecting unit, the current output unit, and the comparator are packaged in one body.
  • the LED dimming driving module, the backlight module and the liquid crystal display device of the invention can increase the charging rate of the capacitor unit and reduce the capacitance by increasing the current output by the current output unit or reducing the capacitance provided by the capacitor unit.
  • the voltage of the unit climbs to the preset threshold voltage to avoid flicker and improve the quality of the light source.
  • FIG. 1 is a circuit diagram of a prior art LED dimming drive circuit
  • FIG. 2 is a circuit diagram of a first embodiment of an LED dimming driving module of the present invention
  • FIG. 3 is a circuit diagram of a second embodiment of the LED dimming driving module of the present invention.
  • FIG. 4 is a circuit diagram of a third embodiment of the LED dimming drive module of the present invention.
  • FIG. 2 is a schematic circuit diagram of an embodiment of the LED dimming driving module of the present invention.
  • the LED dimming drive module includes a duty ratio detecting unit M, a current output unit S0, a comparator B, and a capacitor unit C0.
  • the first input of the comparator B is connected to the capacitor unit C0, and the second input of the comparator B is input with the preset threshold voltage VT.
  • the first input terminal is a non-inverting input terminal, and the second input terminal is an inverting input terminal.
  • the first input is an inverting input and the second input is a non-inverting input.
  • the current output unit S0 is connected to the capacitor unit C0 to charge the capacitor unit C0.
  • the duty ratio detecting unit M is for receiving the pulse width modulation signal P input from the outside and detecting the duty ratio of the pulse width modulation signal P.
  • the duty ratio detecting unit M, the current output unit S0, and the comparator B are packaged in one body.
  • the current output unit S0 increases the output current or the capacitor unit C0 decreases the supplied capacitance to reduce the voltage of the capacitor unit C0 from climbing to the preset threshold voltage VT. time. That is to say, in the case where the capacitance provided by the capacitor unit C0 remains unchanged, the current output unit S0 increases the output current; or in the case where the current output from the current output unit S0 remains unchanged, the capacitor unit C0 is reduced. Capacitance.
  • FIG. 3 is a schematic circuit diagram of a second embodiment of the LED dimming driving module of the present invention.
  • the LED dimming drive module includes a duty ratio detecting unit M1, a current output unit S20, a comparator B1, and a capacitor unit C20.
  • the duty ratio detecting unit M1 and the comparator B1 of the present embodiment have the same technical features as the duty ratio detecting unit M and the comparator B of the first embodiment, and are not described herein again.
  • the capacitance provided by the capacitor unit C20 of the present embodiment remains unchanged, and the current output unit S20 increases the output current.
  • the current output unit S20 outputs the first current
  • the current output unit S20 outputs the second a current, wherein the current value of the second current is less than the current value of the first current.
  • the current output unit S20 includes a first control switch K1, a first current source S1, and a second current source S2, and the capacitor unit C20 includes a first capacitor C1.
  • the duty ratio detecting unit M1 transmits the first control signal to the first control switch K1 when detecting that the duty ratio of the pulse width modulation signal P is less than a predetermined threshold, and transmits the second control when detecting that the duty ratio is greater than a predetermined threshold The signal is to the first control switch K2.
  • the first control switch K1 includes a first end NC1, a second end NC2, a third end NC3, and a fourth end NC4.
  • the first end NC1 is connected to the duty ratio detecting unit M1.
  • the fourth end NC4 is connected to the second end NC2.
  • the fourth end NC4 is connected to the third end NC3.
  • the first current source S1 is connected to the second terminal NC2 of the first control switch K1 to output a first current.
  • the second current source S2 is connected to the third terminal NC3 of the first control switch K1 to output a second current.
  • One end of the first capacitor C1 is connected to the fourth terminal NC4 of the first control switch K1 and the first input terminal of the comparator B1, and the other end of the first capacitor C1 is grounded.
  • the current output unit S0 increases the output current only during the period when the duty ratio is less than a predetermined threshold. It is known to those skilled in the art that if the output of the power supply current is increased, then at the moment of power switching, the voltage on the capacitor unit C20 will be charged by zero volts, thus making the entire LED dimming drive module approximately short-circuited, and will generate a huge Peak current, also known as surge current.
  • the inrush current is typically 20-1000 times the peak operating current. It will cause a lot of trouble for power supply manufacturers and users, especially in places where high reliability and safety are required. Therefore, the industry will have strict standards for inrush current.
  • the current output unit S20 of the embodiment is The first current is generated during the duty cycle less than the predetermined threshold, and the second current is generated during the duty cycle greater than the predetermined threshold, which can suppress the generation of the surge current and improve the reliability and safety of the LED dimming drive module.
  • the LED dimming driving module of the embodiment can switch the first current source S1 or the second current source S2 to output different currents according to the output of the duty detecting unit M1 by setting the first control switch K1, and can quickly switch.
  • the duty ratio is less than the predetermined threshold
  • the first capacitor C1 is supplied with a large current
  • the duty ratio is greater than the predetermined threshold
  • the surge current can be suppressed and the operational reliability can be improved.
  • FIG. 4 is a schematic circuit diagram of a third embodiment of the LED dimming driving module of the present invention.
  • the LED dimming drive module includes a duty ratio detecting unit M2, a current output unit S30, a comparator B2, and a capacitor unit C30.
  • the duty ratio detecting unit M2 and the comparator B2 of the present embodiment have the same technical features as the duty ratio detecting unit M and the comparator B of the first embodiment, and are not described herein again.
  • the current outputted by the current output unit S30 of the embodiment remains unchanged, and the capacitance unit C30 reduces the supplied capacitance.
  • the capacitor unit C30 provides the first capacitor, which accounts for
  • the capacitor unit C30 provides a second capacitor, wherein the capacitance value of the first capacitor is smaller than the capacitance value of the second capacitor.
  • the current output unit S30 includes a third current source S3, and the capacitor unit C30 includes a second control switch K2, a second capacitor C2, and a third capacitor C3.
  • the duty ratio detecting unit M2 transmits the first control signal to the second control switch K2 when detecting that the duty ratio of the pulse width modulation signal P is less than a predetermined threshold, and transmits the second control when detecting that the duty ratio is greater than a predetermined threshold The signal is sent to the second control switch K2.
  • the second control switch K2 includes a first end NO1, a second end NO2, a third end NO3, and a fourth end NO4.
  • the first end NO1 is connected to the duty ratio detecting unit M2.
  • the fourth end NO4 is connected to the second end NO2.
  • the fourth end NO4 is connected to the third end NO3.
  • One end of the second capacitor C2 is connected to the second terminal NO2 of the second control switch K2, the other end of the second capacitor C2 is grounded, and the second capacitor C2 provides the first capacitor.
  • One end of the third capacitor C3 is connected to the third terminal NO3 of the second control switch K2, the other end of the third capacitor C3 is grounded, and the third capacitor C3 provides the second capacitor.
  • the third current source S3 is connected to the fourth terminal NO4 of the second control switch K2 and the first input terminal of the comparator B2.
  • the capacitance provided by the reduction only occurs when the duty ratio is less than a predetermined threshold period, and the surge current generation can also be suppressed.
  • the specific implementation is similar to the current output unit S20 of the second embodiment. More details.
  • the LED dimming driving module of this embodiment can provide different capacitances according to the output of the duty ratio detecting unit M2 by switching the second capacitor C2 or the third capacitor C3 by setting the second control switch K2, and can quickly perform switching in the duty
  • the third current source S3 is supplied with a small capacitance, and when the duty ratio is greater than the predetermined threshold, the surge current can be suppressed, and the operational reliability is improved.
  • the invention also provides a backlight module, which comprises an LED lamp and the LED dimming driving module of the foregoing embodiment.
  • the output of the comparator is compared to output a high level or a low level, which is used to adjust the brightness of the LED light to achieve the purpose of dimming.
  • the present invention also provides a liquid crystal display device comprising the above backlight module.
  • a liquid crystal display device comprising the above backlight module.
  • the LED dimming driving module, the backlight module and the liquid crystal display device of the invention can increase the charging rate of the capacitor unit, reduce the time when the voltage of the capacitor unit climbs to the preset threshold voltage, avoid flickering, and improve the light source. Quality, and by setting the first control switch or the second control switch, it is possible to suppress surge current and improve operational reliability.

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Abstract

本发明公开了一种LED调光驱动模块,其包括占空比检测单元、电流输出单元、比较器和电容单元。比较器的第一输入端连接电容单元,第二输入端输入预设门限电压。电流输出单元连接电容单元。占空比检测单元用于接收外部输入的脉宽调制信号并检测占空比,在检测到占空比小于预定阈值吋,电流输出单元增大输出的电流或者电容单元减小提供的电容,以减少电容单元的电压爬升到预设门限电压的吋间。本发明能够增大电容单元的充电速率。

Description

LED调光驱动模块、背光模组及液晶显示装置
【技术领域】
本发明涉及LED调光领域,特别是涉及一种LED调光驱动模块、背光模组及液晶显示装置。
【背景技术】
随着LED(Light Emitting Diode,发光二级管)背光的节能、环保、高性能等优势的凸显,许多场合都采用LED背光。
由于需要对背光亮度进行调节,因此,需要对LED进行调光。目前,大多数调光方式都采用PWM(Pulse Width Modulation,脉冲宽度调制)调光技术。请参阅图1,图1是现有技术一种LED调光驱动电路的电路示意图。该LED调光驱动电路包括比较器A,电流源S和电容器C,电容器C一端连接比较器A的第一输入端,另一端接地。电流源S连接比较器A的第一输入端。比较器A的第二输入端输入门限电压V。该LED调光驱动电路将响应脉宽调制信号P,在脉宽调制信号P为高电平时,电流源S输出电流,向电容器C充电,当电容器C上的电压爬升到大于门限电压V时,比较器A的输出端输出高电平,用于调节LED背光的亮度。
但是,现有技术的LED调光驱动电路调节LED背光的亮度时,存在闪烁的问题。在脉宽调制信号P的占空比很小的情况下,当LED背光第二次点亮时,由于电容器C上存在电压,该电压足以使LED背光点亮,但持续时间非常短,接着电流源S向电容器C充电,由于脉宽调制信号P占空比很小,电容器C的充电时间很短,那么电容器C上的电压将达不到门限电压V,在脉宽调制信号P经过多个高电平后,电容器C上的电压才爬升到大于门限电压V,比较器A才输出高电平,LED背光点亮,在LED背光点亮期间,由于电容器C的充电电压爬升到门限电压V所需时间较长,导致人眼看到闪烁现象,严重影响光源品质。
【发明内容】
本发明主要解决的技术问题是提供一种LED调光驱动模块、背光模组及液晶显示装置,能够避免产生闪烁现象。
为解决上述技术问题,本发明采用的一个技术方案是:提供一种LED调光驱动模块,该LED调光驱动模块包括占空比检测单元、电流输出单元、比较器和电容单元。比较器的第一输入端连接电容单元,比较器的第二输入端输入预设门限电压。电流输出单元连接电容单元,以向电容单元充电。占空比检测单元用于接收外部输入的脉宽调制信号并检测脉宽调制信号的占空比。占空比检测单元在检测到占空比小于预定阈值时,电流输出单元增大输出的电流或者电容单元减小提供的电容,以减少电容单元的电压爬升到预设门限电压的时间。
其中,占空比检测单元在检测到占空比小于预定阈值时,电流输出单元输出第一电流,占空比检测单元在检测到占空比大于预定阈值时,电流输出单元输出第二电流,其中,第二电流的电流值小于第一电流的电流值。
其中,占空比检测单元在检测到占空比小于预定阈值时,电容单元提供第一电容,占空比检测单元在检测到占空比大于预定阈值时,电容单元提供第二电容,其中,第一电容的电容值小于第二电容的电容值。
其中,电流输出单元包括第一控制开关、第一电流源和第二电流源,电容单元包括第一电容器。其中,占空比检测单元在检测到占空比小于预定阈值时,发送第一控制信号至第一控制开关,在检测到占空比大于预定阈值时,发送第二控制信号至第一控制开关;第一控制开关包括第一端、第二端、第三端和第四端,第一端连接占空比检测单元,在第一端获取第一控制信号时,第四端与第二端连接,在第一端获取第二控制信号时,第四端与第三端连接;第一电流源连接第一控制开关的第二端,输出第一电流;第二电流源连接第一控制开关的第三端,输出第二电流;第一电容器的一端连接第一控制开关的第四端以及比较器的第一输入端,第一电容器的另一端接地。
其中,电流输出单元包括第三电流源,电容单元包括第二控制开关、第二电容器和第三电容器,其中,占空比检测单元在检测到占空比小于预定阈值时,发送第一控制信号至第二控制开关,在检测到占空比大于预定阈值时,发送第二控制信号至第二控制开关;第二控制开关包括第一端、第二端、第三端和第四端,第一端连接占空比检测单元,在第一端获取第一控制信号时,第四端与第二端连接,在第一端获取第二控制信号时,第四端与第三端连接;第二电容器的一端连接第二控制开关的第二端,第二电容器的另一端接地,第二电容器提供第一电容;第三电容器的一端连接第二控制开关的第三端,第三电容器的另一端接地,第三电容器提供第二电容;第三电流源连接第二控制开关的第四端以及比较器的第一输入端。
其中,占空比检测单元、电流输出单元以及比较器封装于一体。
为解决上述技术问题,本发明还采用的一个技术方案是:提供一种背光模组,背光模组包括LED灯和LED调光驱动模块。该LED调光驱动模块包括占空比检测单元、电流输出单元、比较器和电容单元。比较器的第一输入端连接电容单元,比较器的第二输入端输入预设门限电压。电流输出单元连接电容单元,以向电容单元充电。占空比检测单元用于接收外部输入的脉宽调制信号并检测脉宽调制信号的占空比。占空比检测单元在检测到占空比小于预定阈值时,电流输出单元增大输出的电流或者电容单元减小提供的电容,以减少电容单元的电压爬升到预设门限电压的时间,比较器的输出端输出高电平或低电平,用于调节LED灯的亮度。
其中,占空比检测单元在检测到占空比小于预定阈值时,电流输出单元输出第一电流,占空比检测单元在检测到占空比大于预定阈值时,电流输出单元输出第二电流,其中,第二电流的电流值小于第一电流的电流值。
其中,占空比检测单元在检测到占空比小于预定阈值时,电容单元提供第一电容,占空比检测单元在检测到占空比大于预定阈值时,电容单元提供第二电容,其中,第一电容的电容值小于第二电容的电容值。
其中,电流输出单元包括第一控制开关、第一电流源和第二电流源,电容单元包括第一电容器。其中,占空比检测单元在检测到占空比小于预定阈值时,发送第一控制信号至第一控制开关,在检测到占空比大于预定阈值时,发送第二控制信号至第一控制开关;第一控制开关包括第一端、第二端、第三端和第四端,第一端连接占空比检测单元,在第一端获取第一控制信号时,第四端与第二端连接,在第一端获取第二控制信号时,第四端与第三端连接;第一电流源连接第一控制开关的第二端,输出第一电流;第二电流源连接第一控制开关的第三端,输出第二电流;第一电容器的一端连接第一控制开关的第四端以及比较器的第一输入端,第一电容器的另一端接地。
其中,电流输出单元包括第三电流源,电容单元包括第二控制开关、第二电容器和第三电容器,其中,占空比检测单元在检测到占空比小于预定阈值时,发送第一控制信号至第二控制开关,在检测到占空比大于预定阈值时,发送第二控制信号至第二控制开关;第二控制开关包括第一端、第二端、第三端和第四端,第一端连接占空比检测单元,在第一端获取第一控制信号时,第四端与第二端连接,在第一端获取第二控制信号时,第四端与第三端连接;第二电容器的一端连接第二控制开关的第二端,第二电容器的另一端接地,第二电容器提供第一电容;第三电容器的一端连接第二控制开关的第三端,第三电容器的另一端接地,第三电容器提供第二电容;第三电流源连接第二控制开关的第四端以及比较器的第一输入端。
其中,占空比检测单元、电流输出单元以及比较器封装于一体。
为解决上述技术问题,本发明采用的另一个技术方案是,提供一种液晶显示装置,包括背光模组,背光模组包括LED灯和LED调光驱动模块。该LED调光驱动模块包括占空比检测单元、电流输出单元、比较器和电容单元。比较器的第一输入端连接电容单元,比较器的第二输入端输入预设门限电压。电流输出单元连接电容单元,以向电容单元充电。占空比检测单元用于接收外部输入的脉宽调制信号并检测脉宽调制信号的占空比。占空比检测单元在检测到占空比小于预定阈值时,电流输出单元增大输出的电流或者电容单元减小提供的电容,以减少电容单元的电压爬升到预设门限电压的时间,比较器的输出端输出高电平或低电平,用于调节LED灯的亮度。
其中,占空比检测单元在检测到占空比小于预定阈值时,电流输出单元输出第一电流,占空比检测单元在检测到占空比大于预定阈值时,电流输出单元输出第二电流,其中,第二电流的电流值小于第一电流的电流值。
其中,占空比检测单元在检测到占空比小于预定阈值时,电容单元提供第一电容,占空比检测单元在检测到占空比大于预定阈值时,电容单元提供第二电容,其中,第一电容的电容值小于第二电容的电容值。
其中,电流输出单元包括第一控制开关、第一电流源和第二电流源,电容单元包括第一电容器。其中,占空比检测单元在检测到占空比小于预定阈值时,发送第一控制信号至第一控制开关,在检测到占空比大于预定阈值时,发送第二控制信号至第一控制开关;第一控制开关包括第一端、第二端、第三端和第四端,第一端连接占空比检测单元,在第一端获取第一控制信号时,第四端与第二端连接,在第一端获取第二控制信号时,第四端与第三端连接;第一电流源连接第一控制开关的第二端,输出第一电流;第二电流源连接第一控制开关的第三端,输出第二电流;第一电容器的一端连接第一控制开关的第四端以及比较器的第一输入端,第一电容器的另一端接地。
其中,电流输出单元包括第三电流源,电容单元包括第二控制开关、第二电容器和第三电容器,其中,占空比检测单元在检测到占空比小于预定阈值时,发送第一控制信号至第二控制开关,在检测到占空比大于预定阈值时,发送第二控制信号至第二控制开关;第二控制开关包括第一端、第二端、第三端和第四端,第一端连接占空比检测单元,在第一端获取第一控制信号时,第四端与第二端连接,在第一端获取第二控制信号时,第四端与第三端连接;第二电容器的一端连接第二控制开关的第二端,第二电容器的另一端接地,第二电容器提供第一电容;第三电容器的一端连接第二控制开关的第三端,第三电容器的另一端接地,第三电容器提供第二电容;第三电流源连接第二控制开关的第四端以及比较器的第一输入端。
其中,占空比检测单元、电流输出单元以及比较器封装于一体。
综上所述,本发明的LED调光驱动模块、背光模组及液晶显示装置通过增大电流输出单元输出的电流或减小电容单元提供的电容,能够增大电容单元的充电速率,减少电容单元的电压爬升到预设门限电压的时间,避免产生闪烁现象,提高光源品质。
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他目的、特征和优点能够更明显易懂,以下特举较佳实施例,并配合附图,详细说明如下。
【附图说明】
图1是现有技术一种LED调光驱动电路的电路示意图;
图2是本发明LED调光驱动模块第一实施例的电路示意图;
图3是本发明LED调光驱动模块第二实施例的电路示意图;
图4是本发明LED调光驱动模块第三实施例的电路示意图。
【具体实施方式】
下面将结合本发明实施例中的附图,对本发明实施例中的技术方案进行清楚、完整地描述,显然,所描述的实施例仅仅是本发明一部分实施例,而不是全部的实施例。基于本发明中的实施例,本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例,均属于本发明保护的范围。
请参阅图2,图2是本发明LED调光驱动模块实施例的电路示意图。LED调光驱动模块包括占空比检测单元M、电流输出单元S0、比较器B和电容单元C0。
比较器B的第一输入端连接电容单元C0,比较器B的第二输入端输入预设门限电压VT。其中,第一输入端为正相输入端,第二输入端为反相输入端。或者,第一输入端为反相输入端,第二输入端为正相输入端。
电流输出单元S0连接电容单元C0,以向电容单元C0充电。
占空比检测单元M用于接收外部输入的脉宽调制信号P并检测脉宽调制信号P的占空比。
在本实施例中,占空比检测单元M、电流输出单元S0和比较器B封装于一体。
占空比检测单元M在检测到占空比小于预定阈值时,电流输出单元S0增大输出的电流或者电容单元C0减小提供的电容,以减少电容单元C0的电压爬升到预设门限电压VT的时间。也就是说,在电容单元C0提供的电容保持不变的情况下,电流输出单元S0增大输出的电流;或者在电流输出单元S0输出的电流保持不变的情况下,电容单元C0减小提供的电容。这样,无论是增大电流还是减小电容,电容单元C0的充电速率都将加快,电容单元C0的电压能够快速爬升到预设门限电压VT,使比较器B能够快速比较,从而避免产生闪烁现象。
请参阅图3,图3是本发明LED调光驱动模块第二实施例的电路示意图。LED调光驱动模块包括占空比检测单元M1、电流输出单元S20、比较器B1和电容单元C20。本实施例的占空比检测单元M1和比较器B1具有与第一实施例的占空比检测单元M和比较器B相同的技术特征,此处不再赘述。
本实施例的电容单元C20提供的电容保持不变,电流输出单元S20增大输出的电流。占空比检测单元M1在检测到占空比小于预定阈值时,电流输出单元S20输出第一电流,占空比检测单元M1在检测到占空比大于预定阈值时,电流输出单元S20输出第二电流,其中,第二电流的电流值小于第一电流的电流值。
具体地,电流输出单元S20包括第一控制开关K1、第一电流源S1和第二电流源S2,电容单元C20包括第一电容器C1。
占空比检测单元M1在检测到脉宽调制信号P的占空比小于预定阈值时,发送第一控制信号至第一控制开关K1,在检测到占空比大于预定阈值时,发送第二控制信号至第一控制开关K2。
第一控制开关K1包括第一端NC1、第二端NC2、第三端NC3和第四端NC4,第一端NC1连接占空比检测单元M1,在第一端NC1获取第一控制信号时,第四端NC4与第二端NC2连接,在第一端NC1获取第二控制信号时,第四端NC4与第三端NC3连接。
第一电流源S1连接第一控制开关K1的第二端NC2,输出第一电流。第二电流源S2连接第一控制开关K1的第三端NC3,输出第二电流。
第一电容器C1的一端连接第一控制开关K1的第四端NC4以及比较器B1的第一输入端,第一电容器C1的另一端接地。
由此可见,电流输出单元S0增大输出的电流只发生于占空比小于预定阈值期间。本领域技术人员都知道,如果增大电源电流的输出,那么在电源开关瞬间,电容单元C20上的电压将由零伏起充,因此使得整个LED调光驱动模块近似短路状态,并且会产生巨大的峰值电流,这个峰值电流也被称作浪涌电流。浪涌电流通常为正常工作电流峰值的20-1000倍。会给电源厂商和用户带来很多麻烦,尤其是在需要高可靠性和安全性的场合,因此,对于浪涌电流,业界都会有严格标准。
如果无论占空比小于或大于预定阈值期间,电流输出单元S20都增大输出的电流,那么势必会产生浪涌电流,对LED调光驱动模块不利,因此,本实施例的电流输出单元S20于占空比小于预定阈值期间才产生第一电流,而于占空比大于预定阈值期间产生第二电流,能够抑制浪涌电流产生,提高LED调光驱动模块的可靠性和安全性。
本实施例的LED调光驱动模块通过设置第一控制开关K1,能够根据占空比检测单元M1的输出切换第一电流源S1或第二电流源S2输出不同的电流,能够快速进行切换,在占空比小于预定阈值时,为第一电容器C1提供较大电流,在占空比大于预定阈值时,能够抑制浪涌电流,提高工作可靠性。
请参阅图4,图4是本发明LED调光驱动模块第三实施例的电路示意图。 LED调光驱动模块包括占空比检测单元M2、电流输出单元S30、比较器B2和电容单元C30。本实施例的占空比检测单元M2和比较器B2具有与第一实施例的占空比检测单元M和比较器B相同的技术特征,此处不再赘述。
本实施例的电流输出单元S30输出的电流保持不变,电容单元C30减小提供的电容,占空比检测单元M2在检测到占空比小于预定阈值时,电容单元C30提供第一电容,占空比检测单元M2在检测到占空比大于预定阈值时,电容单元C30提供第二电容,其中,第一电容的电容值小于第二电容的电容值。
具体地,电流输出单元S30包括第三电流源S3,电容单元C30包括第二控制开关K2、第二电容器C2和第三电容器C3。
占空比检测单元M2在检测到脉宽调制信号P的占空比小于预定阈值时,发送第一控制信号至第二控制开关K2,在检测到占空比大于预定阈值时,发送第二控制信号至第二控制开关K2。
第二控制开关K2包括第一端NO1、第二端NO2、第三端NO3和第四端NO4,第一端NO1连接占空比检测单元M2,在第一端NO1获取第一控制信号时,第四端NO4与第二端NO2连接,在第一端NO1获取第二控制信号时,第四端NO4与第三端NO3连接。
第二电容器C2的一端连接第二控制开关K2的第二端NO2,第二电容器C2的另一端接地,第二电容器C2提供第一电容。第三电容器C3的一端连接第二控制开关K2的第三端NO3,第三电容器C3的另一端接地,第三电容器C3提供第二电容。
第三电流源S3连接第二控制开关K2的第四端NO4以及比较器B2的第一输入端。
对于电容单元C30而言,其减小提供的电容只发生于占空比小于预定阈值期间,同样能够抑制浪涌电流产生,具体实现方式与第二实施例的电流输出单元S20类似,此处不再详述。
本实施例的LED调光驱动模块通过设置第二控制开关K2,能够根据占空比检测单元M2的输出切换第二电容器C2或第三电容器C3提供不同的电容,能够快速进行切换,在占空比小于预定阈值时,为第三电流源S3提供较小电容,在占空比大于预定阈值时,能够抑制浪涌电流,提高工作可靠性。
本发明还提供了一种背光模组,背光模组包括LED灯和前述实施例的LED调光驱动模块。比较器的输出端经过比较后输出高电平或低电平,用于调节LED灯的亮度,达到调光的目的。
本发明还提供一种液晶显示装置,液晶显示装置包括上述背光模组。背光模组及液晶显示装置的其它结构请参照现有技术,本发明不作说明。
通过上述方式,本发明的LED调光驱动模块、背光模组及液晶显示装置能够增大电容单元的充电速率,减少电容单元的电压爬升到预设门限电压的时间,避免产生闪烁现象,提高光源品质,并且通过设置第一控制开关或第二控制开关,能够抑制浪涌电流,提高工作可靠性。
以上所述仅为本发明的实施例,并非因此限制本发明的专利范围,凡是利用本发明说明书及附图内容所作的等效结构或等效流程变换,或直接或间接运用在其他相关的技术领域,均同理包括在本发明的专利保护范围内。

Claims (18)

  1. 一种LED调光驱动模块,其中,所述LED调光驱动模块包括占空比检测单元、电流输出单元、比较器和电容单元,其中:
    所述比较器的第一输入端连接所述电容单元,所述比较器的第二输入端输入预设门限电压;
    所述电流输出单元连接所述电容单元,以向所述电容单元充电;
    所述占空比检测单元用于接收外部输入的脉宽调制信号并检测所述脉宽调制信号的占空比;
    其中,所述占空比检测单元在检测到所述占空比小于预定阈值时,所述电流输出单元增大输出的电流或者所述电容单元减小提供的电容,以减少所述电容单元的电压爬升到所述预设门限电压的时间。
  2. 根据权利要求1所述的LED调光驱动模块,其中,所述占空比检测单元在检测到所述占空比小于预定阈值时,所述电流输出单元输出第一电流,所述占空比检测单元在检测到所述占空比大于所述预定阈值时,所述电流输出单元输出第二电流,其中,所述第二电流的电流值小于所述第一电流的电流值。
  3. 根据权利要求1所述的LED调光驱动模块,其中,所述占空比检测单元在检测到所述占空比小于所述预定阈值时,所述电容单元提供第一电容,所述占空比检测单元在检测到所述占空比大于所述预定阈值时,所述电容单元提供第二电容,其中,所述第一电容的电容值小于所述第二电容的电容值。
  4. 根据权利要求2所述的LED调光驱动模块,其中,所述电流输出单元包括第一控制开关、第一电流源和第二电流源,所述电容单元包括第一电容器,其中:
    所述占空比检测单元在检测到所述占空比小于所述预定阈值时,发送第一控制信号至所述第一控制开关,在检测到所述占空比大于所述预定阈值时,发送第二控制信号至所述第一控制开关;
    所述第一控制开关包括第一端、第二端、第三端和第四端,所述第一端连接所述占空比检测单元,在所述第一端获取所述第一控制信号时,所述第四端与所述第二端连接,在所述第一端获取所述第二控制信号时,所述第四端与所述第三端连接;
    所述第一电流源连接所述第一控制开关的第二端,输出所述第一电流;
    所述第二电流源连接所述第一控制开关的第三端,输出所述第二电流;
    所述第一电容器的一端连接所述第一控制开关的第四端以及所述比较器的第一输入端,所述第一电容器的另一端接地。
  5. 根据权利要求3所述的LED调光驱动模块,其中,所述电流输出单元包括第三电流源,所述电容单元包括第二控制开关、第二电容器和第三电容器,其中:
    所述占空比检测单元在检测到所述占空比小于所述预定阈值时,发送第一控制信号至所述第二控制开关,在检测到所述占空比大于所述预定阈值时,发送第二控制信号至所述第二控制开关;
    所述第二控制开关包括第一端、第二端、第三端和第四端,所述第一端连接所述占空比检测单元,在所述第一端获取所述第一控制信号时,所述第四端与所述第二端连接,在所述第一端获取所述第二控制信号时,所述第四端与所述第三端连接;
    所述第二电容器的一端连接所述第二控制开关的第二端,所述第二电容器的另一端接地,所述第二电容器提供所述第一电容;
    所述第三电容器的一端连接所述第二控制开关的第三端,所述第三电容器的另一端接地,所述第三电容器提供所述第二电容;
    所述第三电流源连接所述第二控制开关的第四端以及所述比较器的第一输入端。
  6. 根据权利要求1所述的LED调光驱动模块,其中,所述占空比检测单元、所述电流输出单元以及所述比较器封装于一体。
  7. 一种背光模组,其中,所述背光模组包括LED灯和LED调光驱动模块,所述LED调光驱动模块包括占空比检测单元、电流输出单元、比较器和电容单元,其中:
    所述比较器的第一输入端连接所述电容单元,所述比较器的第二输入端输入预设门限电压;
    所述电流输出单元连接所述电容单元,以向所述电容单元充电;
    所述占空比检测单元用于接收外部输入的脉宽调制信号并检测所述脉宽调制信号的占空比;
    其中,所述占空比检测单元在检测到所述占空比小于预定阈值时,所述电流输出单元增大输出的电流或者所述电容单元减小提供的电容,以减少所述电容单元的电压爬升到所述预设门限电压的时间,所述比较器的输出端输出高电平或低电平,用于调节所述LED灯的亮度。
  8. 根据权利要求7所述的背光模组,其中,所述占空比检测单元在检测到所述占空比小于预定阈值时,所述电流输出单元输出第一电流,所述占空比检测单元在检测到所述占空比大于所述预定阈值时,所述电流输出单元输出第二电流,其中,所述第二电流的电流值小于所述第一电流的电流值。
  9. 根据权利要求7所述的背光模组,其中,所述占空比检测单元在检测到所述占空比小于所述预定阈值时,所述电容单元提供第一电容,所述占空比检测单元在检测到所述占空比大于所述预定阈值时,所述电容单元提供第二电容,其中,所述第一电容的电容值小于所述第二电容的电容值。
  10. 根据权利要求8所述的背光模组,其中,所述电流输出单元包括第一控制开关、第一电流源和第二电流源,所述电容单元包括第一电容器,其中:
    所述占空比检测单元在检测到所述占空比小于所述预定阈值时,发送第一控制信号至所述第一控制开关,在检测到所述占空比大于所述预定阈值时,发送第二控制信号至所述第一控制开关;
    所述第一控制开关包括第一端、第二端、第三端和第四端,所述第一端连接所述占空比检测单元,在所述第一端获取所述第一控制信号时,所述第四端与所述第二端连接,在所述第一端获取所述第二控制信号时,所述第四端与所述第三端连接;
    所述第一电流源连接所述第一控制开关的第二端,输出所述第一电流;
    所述第二电流源连接所述第一控制开关的第三端,输出所述第二电流;
    所述第一电容器的一端连接所述第一控制开关的第四端以及所述比较器的第一输入端,所述第一电容器的另一端接地。
  11. 根据权利要求9所述的背光模组,其中,所述电流输出单元包括第三电流源,所述电容单元包括第二控制开关、第二电容器和第三电容器,其中:
    所述占空比检测单元在检测到所述占空比小于所述预定阈值时,发送第一控制信号至所述第二控制开关,在检测到所述占空比大于所述预定阈值时,发送第二控制信号至所述第二控制开关;
    所述第二控制开关包括第一端、第二端、第三端和第四端,所述第一端连接所述占空比检测单元,在所述第一端获取所述第一控制信号时,所述第四端与所述第二端连接,在所述第一端获取所述第二控制信号时,所述第四端与所述第三端连接;
    所述第二电容器的一端连接所述第二控制开关的第二端,所述第二电容器的另一端接地,所述第二电容器提供所述第一电容;
    所述第三电容器的一端连接所述第二控制开关的第三端,所述第三电容器的另一端接地,所述第三电容器提供所述第二电容;
    所述第三电流源连接所述第二控制开关的第四端以及所述比较器的第一输入端。
  12. 根据权利要求7所述的背光模组,其中,所述占空比检测单元、所述电流输出单元以及所述比较器封装于一体。
  13. 一种液晶显示装置,其中,所述液晶显示装置包括背光模组,背光模组包括LED灯和LED调光驱动模块,所述LED调光驱动模块包括占空比检测单元、电流输出单元、比较器和电容单元,其中:
    所述比较器的第一输入端连接所述电容单元,所述比较器的第二输入端输入预设门限电压;
    所述电流输出单元连接所述电容单元,以向所述电容单元充电;
    所述占空比检测单元用于接收外部输入的脉宽调制信号并检测所述脉宽调制信号的占空比;
    其中,所述占空比检测单元在检测到所述占空比小于预定阈值时,所述电流输出单元增大输出的电流或者所述电容单元减小提供的电容,以减少所述电容单元的电压爬升到所述预设门限电压的时间,所述比较器的输出端输出高电平或低电平,用于调节所述LED灯的亮度。
  14. 根据权利要求13所述的液晶显示装置,其中,所述占空比检测单元在检测到所述占空比小于预定阈值时,所述电流输出单元输出第一电流,所述占空比检测单元在检测到所述占空比大于所述预定阈值时,所述电流输出单元输出第二电流,其中,所述第二电流的电流值小于所述第一电流的电流值。
  15. 根据权利要求13所述的液晶显示装置,其中,所述占空比检测单元在检测到所述占空比小于所述预定阈值时,所述电容单元提供第一电容,所述占空比检测单元在检测到所述占空比大于所述预定阈值时,所述电容单元提供第二电容,其中,所述第一电容的电容值小于所述第二电容的电容值。
  16. 根据权利要求14所述的液晶显示装置,其中,所述电流输出单元包括第一控制开关、第一电流源和第二电流源,所述电容单元包括第一电容器,其中:
    所述占空比检测单元在检测到所述占空比小于所述预定阈值时,发送第一控制信号至所述第一控制开关,在检测到所述占空比大于所述预定阈值时,发送第二控制信号至所述第一控制开关;
    所述第一控制开关包括第一端、第二端、第三端和第四端,所述第一端连接所述占空比检测单元,在所述第一端获取所述第一控制信号时,所述第四端与所述第二端连接,在所述第一端获取所述第二控制信号时,所述第四端与所述第三端连接;
    所述第一电流源连接所述第一控制开关的第二端,输出所述第一电流;
    所述第二电流源连接所述第一控制开关的第三端,输出所述第二电流;
    所述第一电容器的一端连接所述第一控制开关的第四端以及所述比较器的第一输入端,所述第一电容器的另一端接地。
  17. 根据权利要求15所述的液晶显示装置,其中,所述电流输出单元包括第三电流源,所述电容单元包括第二控制开关、第二电容器和第三电容器,其中:
    所述占空比检测单元在检测到所述占空比小于所述预定阈值时,发送第一控制信号至所述第二控制开关,在检测到所述占空比大于所述预定阈值时,发送第二控制信号至所述第二控制开关;
    所述第二控制开关包括第一端、第二端、第三端和第四端,所述第一端连接所述占空比检测单元,在所述第一端获取所述第一控制信号时,所述第四端与所述第二端连接,在所述第一端获取所述第二控制信号时,所述第四端与所述第三端连接;
    所述第二电容器的一端连接所述第二控制开关的第二端,所述第二电容器的另一端接地,所述第二电容器提供所述第一电容;
    所述第三电容器的一端连接所述第二控制开关的第三端,所述第三电容器的另一端接地,所述第三电容器提供所述第二电容;
    所述第三电流源连接所述第二控制开关的第四端以及所述比较器的第一输入端。
  18. 根据权利要求13所述的液晶显示装置,其中,所述占空比检测单元、所述电流输出单元以及所述比较器封装于一体。
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Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5702825B2 (ja) * 2013-04-22 2015-04-15 ファナック株式会社 液晶表示装置のledバックライトのドライバ回路
CN103440848B (zh) * 2013-09-02 2016-01-20 深圳市华星光电技术有限公司 背光驱动电路
CN105448233B (zh) * 2014-08-26 2018-06-26 上海和辉光电有限公司 Oled像素的驱动方法及有机发光二极管显示装置
CN104299603B (zh) * 2014-10-24 2018-03-27 京东方科技集团股份有限公司 亮度调节装置、方法、led背光装置和液晶显示装置
TW201640955A (zh) * 2015-05-07 2016-11-16 Advanced Analog Technology Inc 可提升面板調光效能的控制裝置及方法
CN107146582B (zh) * 2017-06-14 2019-09-13 昆山龙腾光电有限公司 背光驱动器及其驱动方法
CN108564924B (zh) * 2018-03-22 2021-06-29 昆山龙腾光电股份有限公司 背光调节电路及背光调节方法
CN116560145A (zh) * 2023-05-30 2023-08-08 中国银行股份有限公司 一种检测装置、检测方法、电子设备及存储介质

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101605417A (zh) * 2009-07-15 2009-12-16 西安英洛华微电子有限公司 带调光的led恒流驱动电路
CN102083254A (zh) * 2009-11-30 2011-06-01 成都芯源系统有限公司 适用于三端可控硅调光器的wled驱动电路及驱动方法
CN102708804A (zh) * 2011-10-21 2012-10-03 京东方科技集团股份有限公司 背光的调光方法及背光驱动电路

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19632869C1 (de) * 1996-08-14 1997-09-04 Siemens Ag Verfahren zum Einstellen der Helligkeit einer Anzeige
JP2003264316A (ja) * 2002-03-11 2003-09-19 Fuji Electric Co Ltd Led制御回路
KR20080086798A (ko) * 2007-03-23 2008-09-26 파워 인티그레이션즈, 인크. 고전압 전력 공급 회로용 방법 및 장치
CN102271442B (zh) * 2010-06-01 2014-07-02 登丰微电子股份有限公司 发光二极管驱动电路及控制电路
DE102010039827B4 (de) * 2010-08-26 2018-05-09 Osram Gmbh Verfahren zum Betreiben mindestens einer Leuchtdiode und Leuchtvorrichtung zum Durchführen des Verfahrens
TWI425874B (zh) * 2010-12-23 2014-02-01 Leadtrend Tech Corp 積體電路、控制方法、與光源提供系統
JP5735825B2 (ja) * 2011-03-08 2015-06-17 ローム株式会社 発光素子駆動用のスイッチング電源の制御回路およびそれらを用いた発光装置および電子機器

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101605417A (zh) * 2009-07-15 2009-12-16 西安英洛华微电子有限公司 带调光的led恒流驱动电路
CN102083254A (zh) * 2009-11-30 2011-06-01 成都芯源系统有限公司 适用于三端可控硅调光器的wled驱动电路及驱动方法
CN102708804A (zh) * 2011-10-21 2012-10-03 京东方科技集团股份有限公司 背光的调光方法及背光驱动电路

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CN102984860A (zh) 2013-03-20
DE112012007036B4 (de) 2019-11-21

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