WO2012048495A1 - 显示装置的背光模块的驱动电路及驱动方法 - Google Patents

显示装置的背光模块的驱动电路及驱动方法 Download PDF

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Publication number
WO2012048495A1
WO2012048495A1 PCT/CN2010/079592 CN2010079592W WO2012048495A1 WO 2012048495 A1 WO2012048495 A1 WO 2012048495A1 CN 2010079592 W CN2010079592 W CN 2010079592W WO 2012048495 A1 WO2012048495 A1 WO 2012048495A1
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Prior art keywords
circuit
resonant circuit
operating frequency
frequency value
driving
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English (en)
French (fr)
Inventor
吴梅豪
杨景元
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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 DE112010005934T priority Critical patent/DE112010005934T5/de
Publication of WO2012048495A1 publication Critical patent/WO2012048495A1/zh
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    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/30—Driver circuits
    • H05B45/37—Converter circuits
    • H05B45/3725—Switched mode power supply [SMPS]

Definitions

  • the present invention relates to a driving circuit and a driving method of a backlight module of a display device, and more particularly to a driving circuit and a driving method of a backlight module of a display device capable of improving circuit efficiency.
  • Liquid crystal display (Liquid Crystal Display, LCD) has been widely used in a variety of electronic products, most of the liquid crystal display is a backlight type liquid crystal display, which is composed of a liquid crystal display panel and a backlight module (backlight Module).
  • the backlight module can be divided into a side-light type and a direct-light type according to the incident position of the light source (Direct-light) Type) Two to provide a backlight to the LCD panel.
  • Direct-light Direct-light
  • LED Due to light-emitting diodes (Light-Emitting) Diode, LED) has good optoelectronic properties such as low power consumption, low heat generation, long operating life, impact resistance, small volume, fast response, and color light that emits stable wavelengths, so it is suitable for use in backlight modules.
  • LED backlight modules have adopted resonant circuits as the driving circuit architecture of LEDs.
  • Existing resonant circuits control loads (such as LEDs) at a single fixed frequency.
  • loads such as LEDs
  • fixed-frequency resonant drive circuits cannot be used because load may change or load characteristics may change significantly after prolonged use. Being operated at the best.
  • the parasitic capacitance of the backlight module also affects the parameters of the circuit, thereby affecting the overall operation of the circuit, and failing to operate the circuit in an optimum efficiency state.
  • a main purpose of the present invention is to provide a backlight module, the backlight module includes: a backplane; a plurality of light emitting diodes disposed on the backplane; and a driving circuit electrically connected to the plurality of light emitting diodes, wherein
  • the driving circuit includes: a DC-to-AC power stage circuit; a resonant circuit electrically connected to the DC-to-AC power stage circuit; and a phase detector electrically connected to the resonant circuit for detecting the resonant circuit
  • the voltage phase of the inductor and the capacitor, and the phase detection signal is transmitted; the frequency adjustment module is electrically connected to the phase detector for obtaining the operating frequency value according to the phase detection signal; and driving the chip, the electricity
  • Another object of the present invention is to provide a driving circuit for a backlight module, the driving circuit comprising: a DC-to-AC power stage circuit; a resonant circuit electrically connected to the DC-to-AC power stage circuit; and a phase detector; Electrically connected to the resonant circuit for detecting the voltage phase of the inductor and the capacitor of the resonant circuit, and transmitting a phase detecting signal; the frequency adjusting module is electrically connected to the phase detector for The phase detection signal is used to obtain an operating frequency value; and a driving chip is electrically connected to the frequency adjusting module for driving the DC-to-AC power stage circuit according to the operating frequency value.
  • a further object of the present invention is to provide a driving method of a backlight module, the backlight module comprising a resonant circuit, a frequency adjusting module and a DC-to-AC power stage circuit, the method comprising the steps of: detecting an inductance of the resonant circuit and a voltage phase of the capacitor, and transmitting a phase detection signal; using the frequency adjustment module to obtain an operating frequency value according to the phase detection signal; and driving the DC-to-AC power stage circuit according to the operating frequency value.
  • the resonant circuit is a series resonant circuit or a parallel resonant circuit.
  • the frequency adjustment module adjusts the operating frequency value according to the phase detection signal of the phase detector.
  • the operating frequency value is approximately equal to or equal to the resonant frequency of the resonant circuit.
  • the phase detection signal is provided by a phase detector for detecting the inductance of the resonant circuit and a voltage phase of the capacitor. And transmitting the phase detection signal.
  • the phase detector calculates an optimal operating frequency value according to a voltage phase difference between the inductor and the capacitor, and the frequency adjusting module adjusts the operating frequency value. To the optimal operating frequency value.
  • the driving circuit and the driving method of the backlight module of the display device of the present invention can use the resonant circuit to drive the LED backlight module, and can change the operating frequency of the circuit according to the load condition of the circuit in real time to improve the conversion efficiency of the driving circuit.
  • the driving circuit and the driving method of the backlight module of the display device of the present invention can control the driving mode of the backlight module in real time according to the load condition of the circuit. Therefore, the driving circuit and the driving method of the present invention can use the resonant circuit to drive the LED backlight module, and change the operating frequency of the circuit by detecting the voltage of the resonant circuit and the voltage phase of the capacitor, so that the driving circuit of the backlight module can be operated at any time. In the best condition, the conversion efficiency of the drive circuit is further improved.
  • FIG. 1 is a cross-sectional view showing a backlight module and a display panel in accordance with a first embodiment of the present invention
  • FIG. 2 shows a block diagram of a driving circuit in accordance with an embodiment of the present invention
  • FIG. 3 shows an equivalent circuit diagram of a resonant circuit and a load in accordance with an embodiment of the present invention
  • FIG. 4 is a graph showing characteristic curves of voltage gain and operating frequency of a resonant circuit in accordance with an embodiment of the present invention
  • FIG. 5 is a flow chart showing a method of driving a backlight module in accordance with an embodiment of the present invention.
  • the backlight module 100 of the present embodiment may be a lateral light input or a direct light input light, which is disposed relative to a display panel 101 (for example, a liquid crystal display panel) to form a display device (for example, a liquid crystal display device).
  • the backlight module 100 can be, for example, a direct type backlight module, which includes a back plate 110 and a plurality of light emitting diodes (Light-Emitting). Diode, LED) 120, circuit board 130, reflective layer 140, drive circuit 150, and optical diaphragm 160.
  • the circuit board 130 can be disposed on the back board 110.
  • the LED 120 can be disposed on the circuit board 130 and electrically connected to the circuit board 130 for emitting light to the display panel 101.
  • the reflective layer 140 is formed around the light emitting diode 120 (for example, formed on the circuit board 130 or the back plate 110) to reflect the light of the LED 120.
  • the driving circuit 150 is electrically connected to the LED 120 to drive the LED 120 to emit light.
  • the optical film 160 is disposed above the light emitting diode 120 to improve the uniformity of illumination or the luminous efficiency of the light emitting diode 120.
  • the back plate 110 of the present embodiment is made of an opaque material, such as a plasticized material, a metal material, or a combination of the above materials, for carrying the LED 120 and the circuit board 130 .
  • the LED 120 can be disposed on the circuit board 130 and electrically connected to the driving circuit 150 through the circuit board 130.
  • Circuit board 130 can be a printed circuit board (Printed Circuit board, PCB) or flexible printed circuit board (Flexible Printed Circuits, FPC).
  • the reflective layer 140 can be, for example, a reflective plate, a reflective sheet, or a reflective coating that forms between or around the light emitting diodes 120 for reflecting light.
  • the reflective layer 140 is made of a high reflectivity material such as silver, aluminum, gold, chromium, copper, indium, antimony, nickel, platinum, rhodium, iridium, tin, antimony, tungsten, manganese, any combination thereof.
  • the optical film 160 is, for example, a diffusion sheet, a prism sheet, and a brightness enhancement film (Brightness) Enhancement Film, BEF), Reflective Brightness Enhancement Film (Dual Brightness Enhancement) Film, DBEF), non-multilayer film reflective polarizer (Diffused Reflective Polarizer) Film, DRPF) or any combination of the above, which is located on the light emitting diode 120.
  • BEF Brightness Enhancement Film
  • DBEF Reflective Brightness Enhancement Film
  • DBEF Reflective Brightness Enhancement Film
  • DBEF Reflective Brightness Enhancement Film
  • DRPF non-multilayer film reflective polarizer
  • FIG. 2 is a block diagram showing a driving circuit according to an embodiment of the present invention
  • FIG. 3 is a circuit diagram showing an equivalent circuit of a resonant circuit and a load according to an embodiment of the present invention
  • the driving circuit 150 of this embodiment may include a DC-to-AC power stage circuit 151, a resonance circuit 152, a phase detector 153, a frequency adjustment module 154, and a driving chip 155.
  • the DC-to-AC power stage circuit 151 is configured to convert the DC power into an AC voltage to drive the LED 120.
  • the resonant circuit 152 is electrically connected to the DC-to-AC power stage circuit 151.
  • FIG. 1 is a block diagram showing a driving circuit according to an embodiment of the present invention
  • FIG. 3 is a circuit diagram showing an equivalent circuit of a resonant circuit and a load according to an embodiment of the present invention.
  • the driving circuit 150 of this embodiment may include a DC-to-AC power stage circuit 151, a resonance circuit 152
  • the resonant circuit 152 can utilize a series resonant parallel load (Series).
  • Resonant Parallel Loaded, SRPL Resonant Parallel Loaded
  • the resonant circuit 152 can have an inductance Lr and a capacitance Cr.
  • the inductance Lr is connected in series between the alternating voltage Vs and the capacitor Cr, that is, the resonant circuit 152 is a series resonant circuit, and the alternating voltage Vs is switched by the switching of the alternating current to alternating current power stage circuit 151.
  • the capacitor Cr is connected in parallel to the light emitting diode 120 (load RLED).
  • the resonant circuit 152 can also be a parallel resonant circuit.
  • the resonant circuit 152 of the driving circuit 150 of the present embodiment passes the alternating current wave through the resonant energy storage tank at the operating frequency fs( ⁇ s) (resonant The energy-tank is filtered and generates a high frequency AC sine wave at the load end, and the natural frequency generated by the resonant energy storage tank is the resonant frequency fo( ⁇ o).
  • FIG. 4 there is shown a characteristic diagram of voltage gain and operating frequency of a resonant circuit according to an embodiment of the present invention, wherein the abscissa is a ratio of a resonant frequency to an operating frequency (Wo/Ws), and the ordinate is a voltage. Gain ratio (Vo/Vs).
  • the voltage gain can be approximated as:
  • the resonance circuit 152 can have an optimum conversion efficiency.
  • the resonance frequency fo( ⁇ o) of the resonance circuit 152 is easily changed.
  • the operating frequency fs( ⁇ s) remains unchanged, the operating frequency fs( ⁇ s) cannot approach the resonant frequency fo( ⁇ o), and thus the resonant circuit 152 exhibits non-resistance and reduces its conversion efficiency.
  • the light-emitting diodes 120 loads have different load characteristics before and after lighting. Therefore, if the operating frequency is a fixed value, the resonant circuit 120 cannot obtain an optimum gain value.
  • the phase detector 153 of the driving circuit 150 of the present embodiment is electrically connected to the resonant circuit 152 for detecting the inductance Lr of the resonant circuit 152 and the voltage phases VLr and VCr of the capacitor Cr, and transmitting the phase.
  • the detection result (phase detection signal) of the detector 153 is applied to the frequency adjustment module 154.
  • the phase detector 153 can detect the inductance Lr of the resonant circuit 152 and the voltage phases VLr and VCr of the capacitor Cr, and determine whether the load is inductive or based on the voltage phase difference between the voltage phases VLr and VCr. Capacitance, and the judgment result (phase detection signal) is transmitted to the frequency adjustment module 154.
  • the frequency adjustment module 154 is electrically connected to the phase detector 153 for obtaining the operating frequency value fs( ⁇ s) according to the phase detection signal, and the frequency adjustment module 154 can adjust the operation according to the calculation result of the phase detector 153.
  • the frequency value fs( ⁇ s), and the adjusted result can be transmitted to the driving chip 155.
  • the driving chip 155 is electrically connected between the frequency adjusting module 154 and the DC-to-AC power stage circuit 151 for driving the DC-to-AC power stage circuit 151 according to the adjusted operating frequency value fs( ⁇ s).
  • the driving chip 155 can drive the switching of the DC-to-AC power stage circuit 151 using the operating frequency fs( ⁇ s) calculated by the frequency adjustment module 154.
  • the phase detector 153 can detect the inductance Lr of the resonant circuit 152 and the voltage phases VLr and VCr of the capacitor Cr, and calculate an optimal operating frequency according to the voltage phase difference between the voltage phases VLr and VCr.
  • the value (for example, substantially equal to the resonant frequency), and the calculation result (phase detection signal) of the phase detector 153 is transmitted to the frequency adjustment module 154, the frequency adjustment module 154 can adjust the operating frequency value fs( ⁇ s) to the optimum. Operating frequency value.
  • the driving circuit of the backlight module of the present embodiment can change the operating frequency fs( ⁇ s) of the resonant circuit 152 by detecting the inductance Lr of the resonant circuit 152 and the voltage phases VLr, VCr of the capacitor Cr, so that the operating frequency of the resonant circuit 152 Fs( ⁇ s) can be close to or substantially equal to the resonant frequency fo( ⁇ o) in real time. Therefore, the overall circuit can operate on a purely resistive load to increase the overall conversion efficiency of the circuit.
  • the phase detector 153 of the driving circuit 150 can detect the inductance Lr of the resonant circuit 152 and the voltage phases VLr and VCr of the capacitor Cr, and transmit the phase detection signal (detection result) ) to the frequency adjustment module 154 (step S201). Then, the frequency adjustment module 154 can perform calculation according to the phase detection signal of the phase detector 153 to obtain a corresponding operation frequency value fs( ⁇ s), and can transmit the adjusted result to the driving chip 155 (step S202). . Next, the driving chip 155 can drive the DC-to-AC power stage circuit 151 in accordance with the adjusted operating frequency value fs( ⁇ s) (step S203).
  • the driving circuit and the driving method of the backlight module of the display device of the present invention can control the driving mode of the backlight module in real time according to the load condition of the circuit. Therefore, the driving circuit and the driving method of the present invention can use the resonant circuit to drive the LED backlight module, and change the operating frequency of the circuit by detecting the voltage of the resonant circuit and the voltage phase of the capacitor, so that the driving circuit of the backlight module can be operated at any time. In the best condition, the conversion efficiency of the drive circuit is further improved.

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Description

显示装置的背光模块的驱动电路及驱动方法 技术领域
本发明涉及一种显示装置的背光模块的驱动电路及驱动方法，特别是涉及一种可改善电路效率的显示装置的背光模块的驱动电路及驱动方法。
 背景技术
液晶显示器(Liquid Crystal Display，LCD)已被广泛应用于各种电子产品中，液晶显示器大部分为背光型液晶显示器，其是由液晶显示面板及背光模块(backlight module)所组成。背光模块可依照光源入射位置的不同分成侧向式入光(Side-light type)与直下式入光(Direct-light type)两种，藉以提供背光源至液晶显示面板。
由于发光二极管(Light-Emitting Diode，LED)具有低耗电量、低发热量、操作寿命长、耐撞击、体积小、反应速度快、以及可发出稳定波长的色光等良好光电特性，因而适合应用于背光模块的光源。
目前，LED背光模块已采用谐振式电路来作为LED的驱动电路架构。现有的谐振式电路是以单一固定的频率来控制负载(如LED)，然而，由于负载可能改变，或者负载于长时间使用之后负载特性可能大幅改变，因而使用固定频率的谐振式驱动电路无法被操作在最佳状态。再者，当背光模块的背板材料为金属材料时，背光模块的寄生电容亦会影响电路的参数，进而影响电路的整体操作，而无法使电路操作于最佳的效率状态。
故，有必要提供一种显示装置的背光模块的驱动电路及驱动方法，以解决现有技术所存在的问题。
 技术问题
本发明的主要目的在于提供一种背光模块，所述背光模块包括：背板；若干个发光二极管，设置于所述背板上；以及驱动电路，电性连接于所述若干个发光二极管，其中所述驱动电路包括：直流转交流功率级电路；谐振电路，电性连接于所述直流转交流功率级电路；相位侦测器，电性连接于所述谐振电路，用以检测所述谐振电路的电感及电容的电压相位，并传送相位侦测信号；频率调节模块，电性连接于所述相位侦测器，用以依据所述相位侦测信号来得到操作频率值；以及驱动芯片，电性连接于所述频率调节模块，用以依据所述操作频率值来驱动所述直流转交流功率级电路，其中所述操作频率值是接近或等于所述谐振电路的谐振频率。
本发明的另一目的在于提供一种背光模块的驱动电路，所述驱动电路包括：直流转交流功率级电路；谐振电路，电性连接于所述直流转交流功率级电路；相位侦测器，电性连接于所述谐振电路，用以检测所述谐振电路的电感及电容的电压相位，并传送相位侦测信号；频率调节模块，电性连接于所述相位侦测器，用以依据所述相位侦测信号来得到操作频率值；以及驱动芯片，电性连接于所述频率调节模块，用以依据所述操作频率值来驱动所述直流转交流功率级电路。
本发明的又一目的在于提供一种背光模块的驱动方法，所述背光模块包括谐振电路，频率调节模块及直流转交流功率级电路，所述方法包括如下步骤：检测所述谐振电路的电感及电容的电压相位，并传送相位侦测信号；利用所述频率调节模块来依据所述相位侦测信号而得到操作频率值；以及依据所述操作频率值来驱动所述直流转交流功率级电路。
。
 技术解决方案
在本发明的一实施例中，所述谐振电路为串联谐振电路或并联谐振电路。
在本发明的一实施例中，所述频率调节模块是依据所述相位侦测器的所述相位侦测信号来调整所述操作频率值。
在本发明的一实施例中，所述操作频率值是接近或等于所述谐振电路的谐振频率。
在本发明的一实施例中，所述相位侦测信号是由相位侦测器来提供，所述相位侦测器是用以检测所述谐振电路的所述电感及所述电容的电压相位，并传送所述相位侦测信号。
在本发明的一实施例中，所述相位侦测器是依据所述电感及电容之间的电压相位差来计算得到一最佳操作频率值，所述频率调节模块是调整所述操作频率值至所述最佳操作频率值。
本发明的显示装置的背光模块的驱动电路及驱动方法可利用谐振式电路来驱动LED背光模块，并可实时地依据电路的负载状况来改变电路的操作频率，以提高驱动电路的转换效率。
 有益效果
本发明的显示装置的背光模块的驱动电路及驱动方法可实时地依据电路的负载状况来控制背光模块的驱动方式。因此，本发明的驱动电路及驱动方法可利用谐振式电路来驱动LED背光模块，并通过侦测谐振电路的电感及电容的电压相位来改变电路的操作频率，使得背光模块的驱动电路可随时操作在最佳状态，进而提高驱动电路的转换效率。
 附图说明
为让本发明的上述内容能更明显易懂，下文特举优选实施例，并配合所附图式，作详细说明如下：
图1显示依照本发明的第一实施例的背光模块与显示面板的剖面示意图；
图2显示依照本发明的一实施例的驱动电路的方块图；
图3显示依照本发明的一实施例的谐振电路及负载的等效电路图；
图4显示依照本发明的一实施例的谐振电路的电压增益与操作频率的特性曲线图；以及
图5显示依照本发明的一实施例的背光模块的驱动方法的方法流程图。
 本发明的最佳实施方式
以下各实施例的说明是参考附加的图式，用以例示本发明可用以实施的特定实施例。本发明所提到的方向用语，例如「上」、「下」、「前」、「后」、「左」、「右」、「内」、「外」、「侧面」等，仅是参考附加图式的方向。因此，使用的方向用语是用以说明及理解本发明，而非用以限制本发明。
在图中，结构相似的单元是以相同标号表示。
请参照图1，其显示依照本发明的一实施例的背光模块与显示面板的剖面示意图。本实施例的背光模块100可为侧向式入光或直下式入光，其相对于一显示面板101(例如液晶显示面板)来设置，而形成一显示装置(例如液晶显示装置)。在本实施例中，背光模块100可例如为直下式背光模块，其包括背板110、若干个发光二极管(Light-Emitting Diode，LED)120、电路板130、反射层140、驱动电路150及光学膜片160。电路板130可设置于背板110上，发光二极管120可设置于电路板130上，并电性连接于电路板130，用以发光来提供光线至显示面板101。反射层140是形成于发光二极管120的周围(例如形成于电路板130或背板110上)，用以反射发光二极管120的光线。驱动电路150是电性连接于发光二极管120，以驱动发光二极管120来发光。光学膜片160是设置于发光二极管120上方，用以改善发光二极管120的发光均匀性或发光效率。
如图1所示，本实施例的背板110是由不透光材质所制成，例如：塑化材料、金属材料或上述材料的组合，用以承载发光二极管120及电路板130。发光二极管120可设置于电路板130上，并通过电路板130来电性连接于驱动电路150。电路板130可为印刷电路板(Printed circuit board，PCB)或柔性印刷电路板(Flexible Printed Circuits，FPC)。反射层140可例如为反射板、反射片或反射涂层，其形成发光二极管120之间或其周围，用以反射光线。此反射层140是由高反射率材料所制成，例如银、铝、金、铬、铜、铟、铱、镍、铂、铼、铑、锡、钽、钨、锰、其上述任意组合的合金或耐黄化且耐热的白色反射漆料，用以反射发光二极管120的光线。光学膜片160例如为：扩散片、棱镜片、增亮膜(Brightness Enhancement Film，BEF)、反射式增亮膜(Dual Brightness Enhancement Film，DBEF)、非多层膜式反射偏光片(Diffused Reflective Polarizer Film，DRPF)或上述的任意组合，其位于发光二极管120上。
请参照图2和图3，图2显示依照本发明的一实施例的驱动电路的方块图，图3显示依照本发明的一实施例的谐振电路及负载的等效电路图。本实施例的驱动电路150可包括直流转交流功率级电路151、谐振电路152、相位侦测器153、频率调节模块154及驱动芯片155。直流转交流功率级电路151是用以将直流电源转换成交流电压，以驱动发光二极管120。谐振电路152是电性连接于直流转交流功率级电路151，在本实施例中，如图3所示，谐振电路152可利用一次串联谐振并联负载(Series Resonant Parallel Loaded，SRPL)的方式将交流方波转换为交流弦波, 以驱动发光二极管120。谐振电路152可具有电感Lr及电容Cr，电感Lr是串联于交流电压Vs与电容Cr之间，亦即谐振电路152为串联谐振电路，交流电压Vs是经过直流转交流功率级电路151的开关切换而形成交流方波形式，电容Cr是并联于发光二极管120(负载RLED)。
在一实施例中，谐振电路152亦可为并联谐振电路。
如图2所示，本实施例的驱动电路150的谐振电路152是以操作频率fs(ωs)将交流方波经共振储能槽(resonant energy-tank)进行滤波，并于负载端产生高频交流弦波，而共振储能槽所产生的自然频率则为谐振频率fo(ωo)。
请参照图4，其显示依照本发明的一实施例的谐振电路的电压增益与操作频率的特性曲线图，其中横座标为谐振频率与操作频率之比(Wo/Ws)，纵座标为电压增益比(Vo/Vs)。由图可知，当操作频率fs(ωs)接近或实质等于谐振频率fo(ωo)时，电压增益可近似为：
.................................................................(1)
且质量(quality)因子Q：
.................................................................(2)
由上述公式(1)、(2)可知，当谐振电路152的增益值趋近于无穷大时，亦即谐振电路152可视为纯电阻性，此时，谐振电路152可具有最佳的转换效率。然而，在实际操作情况中，当负载的特性改变或金属制的背板110具有寄生电容时，谐振电路152的谐振频率fo(ωo)容易被改变。此时，若操作频率fs(ωs)仍维持不变时，则操作频率fs(ωs)无法接近谐振频率fo(ωo)，因而谐振电路152是呈现非电阻性，而降低其转换效率。例如，发光二极管120(负载)在点亮前后，其负载特性并不相同。因此，若操作频率为一固定值，则谐振电路120无法得到最佳的增益值。
如图2所示，本实施例的驱动电路150的相位侦测器153是电性连接于谐振电路152，用以检测谐振电路152的电感Lr及电容Cr的电压相位VLr、VCr，并传送相位侦测器153的检测结果(相位侦测信号)至频率调节模块154。在一实施例中，相位侦测器153可检测谐振电路152的电感Lr及电容Cr的电压相位VLr、VCr，并依据电压相位VLr、VCr之间的电压相位差来判断其负载为电感性或电容性，并将判断结果(相位侦测信号)传送至频率调节模块154。频率调节模块154是电性连接于相位侦测器153，用以依据相位侦测信号来取得操作频率值fs(ωs)，频率调节模块154可依据相位侦测器153的计算结果来调整此操作频率值fs(ωs)，并可将调整后的结果传送至驱动芯片155。驱动芯片155是电性连接于频率调节模块154与直流转交流功率级电路151之间，用以依据调整后的操作频率值fs(ωs)来驱动直流转交流功率级电路151。驱动芯片155可使用频率调节模块154所计算出的操作频率fs(ωs)来驱动直流转交流功率级电路151的开关。
在一实施例中，相位侦测器153可检测谐振电路152的电感Lr及电容Cr的电压相位VLr、VCr，并依据电压相位VLr、VCr之间的电压相位差来计算得到一最佳操作频率值(例如实质等于谐振频率)，并将相位侦测器153的计算结果(相位侦测信号)传送至频率调节模块154，则频率调节模块154可调整此操作频率值fs(ωs)至最佳操作频率值。
因此，本实施例的背光模块的驱动电路可通过侦测谐振电路152的电感Lr及电容Cr的电压相位VLr、VCr来改变谐振电路152的操作频率fs(ωs)，使得谐振电路152的操作频率fs(ωs)可实时地接近或实质等于谐振频率fo(ωo)。因此，整体电路可操作于纯电阻性负载，以提高电路的整体转换效率。
请参照图5，其显示依照本发明的一实施例的背光模块的驱动方法的方法流程图。当进行本实施例的背光模块100的驱动方法时，驱动电路150的相位侦测器153可检测谐振电路152的电感Lr及电容Cr的电压相位VLr、VCr，并传送相位侦测信号(检测结果)至频率调节模块154(步骤S201)。接着，频率调节模块154可依据相位侦测器153的相位侦测信号来进行计算，以得到对应的操作频率值fs(ωs)，并可将调整后的结果传送至驱动芯片155(步骤S202)。接着，驱动芯片155可依据调整后的操作频率值fs(ωs)来驱动直流转交流功率级电路151(步骤S203)。
由上述可知，本发明的显示装置的背光模块的驱动电路及驱动方法可实时地依据电路的负载状况来控制背光模块的驱动方式。因此，本发明的驱动电路及驱动方法可利用谐振式电路来驱动LED背光模块，并通过侦测谐振电路的电感及电容的电压相位来改变电路的操作频率，使得背光模块的驱动电路可随时操作在最佳状态，进而提高驱动电路的转换效率。
综上所述，虽然本发明已以优选实施例揭露如上，但上述优选实施例并非用以限制本发明，本领域的普通技术人员，在不脱离本发明的精神和范围内，均可作各种更动与润饰，因此本发明的保护范围以权利要求界定的范围为准。
 本发明的实施方式
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Claims (17)

  1. 一种背光模块，其特征在于：所述背光模块包括：
    背板；
    若干个发光二极管，设置于所述背板上；以及
    驱动电路，电性连接于所述若干个发光二极管，其中所述驱动电路包括：
    直流转交流功率级电路；
    谐振电路，电性连接于所述直流转交流功率级电路；
    相位侦测器，电性连接于所述谐振电路，用以检测所述谐振电路的电感及电容的电压相位，并传送相位侦测信号；
    频率调节模块，电性连接于所述相位侦测器，用以依据所述相位侦测信号来得到操作频率值；以及
    驱动芯片，电性连接于所述频率调节模块，用以依据所述操作频率值来驱动所述直流转交流功率级电路，其中所述操作频率值是等于所述谐振电路的谐振频率。
  2. 根据权利要求1所述的背光模块，其特征在于：所述谐振电路为串联谐振电路。
  3. 根据权利要求1所述的背光模块，其特征在于：所述谐振电路为并联谐振电路。
  4. 根据权利要求1所述的背光模块，其特征在于：所述频率调节模块是依据所述相位侦测器的所述相位侦测信号来调整所述操作频率值。
  5. 根据权利要求1所述的背光模块，其特征在于：所述相位侦测器是依据所述电感及电容之间的电压相位差来计算得到一最佳操作频率值，所述频率调节模块是调整所述操作频率值至所述最佳操作频率值。
  6. 一种背光模块的驱动电路，其特征在于：所述驱动电路包括：
    直流转交流功率级电路；
    谐振电路，电性连接于所述直流转交流功率级电路；
    相位侦测器，电性连接于所述谐振电路，用以检测所述谐振电路的电感及电容的电压相位，并传送相位侦测信号；
    频率调节模块，电性连接于所述相位侦测器，用以依据所述相位侦测信号来得到操作频率值；以及
    驱动芯片，电性连接于所述频率调节模块，用以依据所述操作频率值来驱动所述直流转交流功率级电路。
  7. 根据权利要求6所述的驱动电路，其特征在于：所述谐振电路为串联谐振电路。
  8. 根据权利要求6所述的驱动电路，其特征在于：所述谐振电路为并联谐振电路。
  9. 根据权利要求6所述的驱动电路，其特征在于：所述频率调节模块是依据所述相位侦测器的所述相位侦测信号来调整所述操作频率值。
  10. 根据权利要求6所述的驱动电路，其特征在于：所述操作频率值是等于所述谐振电路的谐振频率。
  11. 根据权利要求6所述的驱动电路，其特征在于：所述相位侦测器是依据所述电感及电容之间的电压相位差来计算得到一最佳操作频率值，所述频率调节模块是调整所述操作频率值至所述最佳操作频率值。
  12. 一种背光模块的驱动方法，其特征在于：所述背光模块包括谐振电路，频率调节模块及直流转交流功率级电路，所述方法包括如下步骤：
    检测所述谐振电路的电感及电容的电压相位，并传送相位侦测信号；
    利用所述频率调节模块来依据所述相位侦测信号而得到操作频率值；以及
    依据所述操作频率值来驱动所述直流转交流功率级电路。
  13. 根据权利要求12所述的方法，其特征在于：所述谐振电路为串联谐振电路。
  14. 根据权利要求12所述的方法，其特征在于：所述谐振电路为并联谐振电路。
  15. 根据权利要求12所述的方法，其特征在于：所述相位侦测信号是由相位侦测器来提供，所述相位侦测器是用以检测所述谐振电路的所述电感及所述电容的电压相位，并传送所述相位侦测信号。
  16. 根据权利要求15所述的方法，其特征在于：所述相位侦测器是依据所述电感及电容之间的电压相位差来计算得到一最佳操作频率值，所述频率调节模块是调整所述操作频率值至所述最佳操作频率值。
  17. 根据权利要求12所述的方法，其特征在于：所述操作频率值是等于所述谐振电路的谐振频率。
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI627621B (zh) * 2013-04-19 2018-06-21 仁寶電腦工業股份有限公司 背光驅動模組

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1540608A (zh) * 2003-03-14 2004-10-27 三星电子株式会社 驱动显示器中光源的装置和方法
CN101083863A (zh) * 2006-01-26 2007-12-05 光诠科技股份有限公司 放电管用驱动电路及其控制方法
WO2009001409A1 (ja) * 2007-06-27 2008-12-31 Tamura Corporation 発光体の駆動周波数制御装置及び制御方法
CN101727831A (zh) * 2008-10-10 2010-06-09 华映视讯（吴江）有限公司 背光模组的驱动电路及其方法

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001126891A (ja) * 1999-10-28 2001-05-11 Murata Mfg Co Ltd 圧電トランスインバータ
CN1200327C (zh) * 2001-06-14 2005-05-04 英业达股份有限公司 多频式高压产生装置
KR100900463B1 (ko) * 2002-12-06 2009-06-02 삼성전자주식회사 전원공급장치 및 이를 이용한 액정표시장치
US7067957B2 (en) * 2003-12-29 2006-06-27 Zippy Technology Corp. Ceramic transformer level driving circuit
JP4101228B2 (ja) * 2004-03-19 2008-06-18 昌和 牛嶋 面光源用放電管並列点灯システム
JP4908760B2 (ja) * 2005-01-12 2012-04-04 昌和 牛嶋 電流共振型インバータ回路
TWI285350B (en) * 2005-07-29 2007-08-11 Innolux Display Corp A liquid crystal display
KR101159354B1 (ko) * 2005-12-08 2012-06-25 엘지디스플레이 주식회사 인터버의 구동 장치 및 방법, 그리고 그를 이용한영상표시기기
CN101848591B (zh) * 2009-03-25 2012-12-19 华映视讯（吴江）有限公司 背光系统的驱动电路

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1540608A (zh) * 2003-03-14 2004-10-27 三星电子株式会社 驱动显示器中光源的装置和方法
CN101083863A (zh) * 2006-01-26 2007-12-05 光诠科技股份有限公司 放电管用驱动电路及其控制方法
WO2009001409A1 (ja) * 2007-06-27 2008-12-31 Tamura Corporation 発光体の駆動周波数制御装置及び制御方法
CN101727831A (zh) * 2008-10-10 2010-06-09 华映视讯（吴江）有限公司 背光模组的驱动电路及其方法

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI627621B (zh) * 2013-04-19 2018-06-21 仁寶電腦工業股份有限公司 背光驅動模組

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