CN101436393B - Light-emitting diode backlight module and its driving circuit and method - Google Patents

Abstract

A light emitting diode backlight module, a driving circuit and a driving method thereof are provided. The driving circuit provided by the invention is suitable for driving at least one light emitting diode in at least one area of light emitting units in the light emitting diode backlight module, and comprises a latch unit and a switch unit. The latch unit is used for receiving control backlight data and latching the control backlight data in a picture period according to a trigger signal so as to output a control signal. The switch unit is coupled with the latch unit and the light emitting diode and used for receiving the control signal and determining whether the light emitting diode emits light or not. The invention can greatly reduce the transmission line and the transmission time, greatly reduce the manufacturing cost, and greatly increase the flexibility of the PWM control mode after adaptively changing the control backlight data provided by the backlight controller or the time schedule controller.

Description

Translated fromChinese

发光二极管背光模块及其驱动电路与方法Light-emitting diode backlight module and its driving circuit and method

技术领域technical field

本发明涉及一种背光模块，且特别涉及一种发光二极管背光模块及其驱动电路与方法。The invention relates to a backlight module, and in particular to a light emitting diode backlight module and its driving circuit and method.

背景技术Background technique

近年来，随着半导体科技蓬勃发展，便携式电子产品及平面显示器产品也随之兴起。而在众多平面显示器的类型当中，液晶显示器(Liquid CrystalDisplay，LCD)基于其低电压操作、无辐射线散射、重量轻以及体积小等优点，随即已成为显示器产品的主流。In recent years, with the vigorous development of semiconductor technology, portable electronic products and flat panel display products are also emerging. Among the types of flat panel displays, Liquid Crystal Display (LCD) has become the mainstream of display products due to its advantages of low voltage operation, no radiation scattering, light weight and small size.

一般而言，由于液晶显示面板并不具备自发光的特性，因此必须在液晶显示面板的下方放置背光模块，借以提供液晶显示面板所需的光源。传统的背光模块大致可以分为两类，其一为由冷阴极管(cold cathode FluorescentLamps，CCFL)所组成的背光模块，而另一则为由发光二极管(light emittingdiode，LED)所组成的背光模块。其中，由于发光二极管背光模块可以提升液晶显示器的色域，故而现今各家厂商大多以发光二极管背光模块来取代冷阴极管背光模块。Generally speaking, since the liquid crystal display panel does not have the characteristic of self-illumination, a backlight module must be placed under the liquid crystal display panel to provide the light source required by the liquid crystal display panel. Traditional backlight modules can be roughly divided into two categories, one is a backlight module composed of cold cathode fluorescent lamps (CCFL), and the other is a backlight module composed of light emitting diodes (light emitting diodes, LEDs). . Among them, since the LED backlight module can improve the color gamut of the liquid crystal display, most manufacturers now replace the cold-cathode tube backlight module with the LED backlight module.

然而，由于现今驱动发光二极管背光模块的方式大多采用脉冲宽度调制(pulse width modulation，PWM)与分区控制的概念，故而当分区控制的区域数增加时，可能会造成以下几点缺点：However, since most of the current methods of driving LED backlight modules adopt the concepts of pulse width modulation (PWM) and partition control, when the number of zones controlled by partitions increases, the following disadvantages may occur:

1、传输线与传输时间大幅地增加；1. The transmission line and transmission time are greatly increased;

2、PWM的控制方式较没有弹性；以及2. The PWM control method is less flexible; and

3、每一分区控制的区域内皆必须配置一个电流控制器，故而会大幅地增加制作成本。3. A current controller must be installed in the area controlled by each partition, so the production cost will be greatly increased.

发明内容Contents of the invention

有鉴于此，本发明提供一种发光二极管背光模块及其驱动电路与方法，借以减少传输线与传输时间、增加PWM的控制方式的弹性，并且采用定电压控制的方式来降低制作成本。In view of this, the present invention provides an LED backlight module and its driving circuit and method, thereby reducing the transmission line and transmission time, increasing the flexibility of the PWM control method, and reducing the production cost by adopting the constant voltage control method.

本发明提供一种驱动电路，其适于驱动液晶显示器的发光二极管背光模块内的至少一区发光单元中的至少一发光二极管。本发明所提出的驱动电路包括闩锁单元与开关单元。其中，闩锁单元用以接收一控制背光数据，并依据一触发信号而于一画面期间内对所述控制背光数据进行闩锁，借以输出一控制信号。开关单元耦接闩锁单元与发光二极管，用以接收所述控制信号，并据以决定发光二极管是否发光。The invention provides a driving circuit, which is suitable for driving at least one light emitting diode in at least one area light emitting unit in a light emitting diode backlight module of a liquid crystal display. The driving circuit proposed by the present invention includes a latch unit and a switch unit. Wherein, the latch unit is used for receiving backlight control data, and latching the backlight control data within a frame period according to a trigger signal, so as to output a control signal. The switch unit is coupled to the latch unit and the LED to receive the control signal and determine whether the LED emits light or not.

本发明另提供一种驱动方法，其适于驱动一发光二极管背光模块内的至少一区发光单元中的至少一发光二极管。本发明所提出的驱动方法包括：首先，提供一控制背光数据与一触发信号；接着，依据该触发信号而于一画面期间内对该控制背光数据进行闩锁，借以输出一控制信号；最后，依据所述控制信号以驱动发光二极管。The present invention further provides a driving method, which is suitable for driving at least one light emitting diode in at least one area of light emitting units in a light emitting diode backlight module. The driving method proposed by the present invention includes: firstly, providing a control backlight data and a trigger signal; then, according to the trigger signal, latching the control backlight data within a frame period, so as to output a control signal; finally, The LED is driven according to the control signal.

本发明另提供一种具有上述本发明所提出的驱动电路的发光二极管背光模块。The present invention further provides an LED backlight module having the driving circuit proposed by the present invention.

本发明将驱动发光二极管背光模块的每一分区控制的区域内所需的驱动电路排列成矩阵结构，并且以快速扫描的方式来提供触发信号以控制每一区发光单元的发光二极管串，如此设计方式即可以大量减少传输线与传输时间。另外，由于每一驱动电路内又具有闩锁单元以对控制背光数据进行闩锁，所以在快速扫描以提供触发信号来控制每一区发光单元的发光二极管串的同时，并不让每一区发光单元的发光二极管串亮度降低或发生闪烁。每个分区控制的区域中并不需使用电流控制器，如此一来即可大大地将低制作成本。适应性地改变由背光控制器或时序控制器所提供的控制背光数据后，即可大幅地增加PWM的控制方式的弹性。In the present invention, the drive circuits required to drive the LED backlight module in each area controlled by each area are arranged in a matrix structure, and a trigger signal is provided in a fast scanning manner to control the LED strings of the light-emitting units in each area, so designed In this way, the transmission line and transmission time can be greatly reduced. In addition, because there is a latch unit in each driving circuit to latch the control backlight data, so while fast scanning is used to provide a trigger signal to control the light-emitting diode strings of the light-emitting units in each region, each region does not The brightness of the light emitting diode strings of the light emitting unit decreases or flickers. The area controlled by each partition does not need to use a current controller, so that the manufacturing cost can be greatly reduced. After adaptively changing the backlight control data provided by the backlight controller or the timing controller, the flexibility of the PWM control method can be greatly increased.

为让本发明的上述和其他目的、特征和优点能更明显易懂，下文特举本发明几个优选实施例，并配合附图，作详细说明如下。In order to make the above and other objects, features and advantages of the present invention more comprehensible, several preferred embodiments of the present invention will be described in detail below together with the accompanying drawings.

附图说明Description of drawings

图1示出本发明一优选实施例的液晶显示器的方块图。FIG. 1 shows a block diagram of a liquid crystal display of a preferred embodiment of the present invention.

图2示出本发明一优选实施例的发光二极管背光模块的电路示意图。FIG. 2 shows a schematic circuit diagram of an LED backlight module according to a preferred embodiment of the present invention.

图3示出本发明一优选实施例的每一闩锁单元的电路图。FIG. 3 shows a circuit diagram of each latch unit in a preferred embodiment of the present invention.

图4示出本发明一优选实施例的每一开关单元的电路图。FIG. 4 shows a circuit diagram of each switch unit in a preferred embodiment of the present invention.

图5示出本发明一优选实施例的每一驱动电路的操作时序图。FIG. 5 shows an operation timing diagram of each driving circuit in a preferred embodiment of the present invention.

图6示出本发明一优选实施例的驱动方法流程图。Fig. 6 shows a flowchart of a driving method in a preferred embodiment of the present invention.

上述附图中的附图标记说明如下：The reference numerals in the above-mentioned accompanying drawings are explained as follows:

100：液晶显示器100: LCD display

101：液晶显示面板101: Liquid crystal display panel

103：发光二极管背光模块103: LED backlight module

105：时序控制器105: Timing controller

107：栅极驱动器107: Gate driver

109：源极驱动器109: Source driver

111：背光控制器111: Backlight controller

201a～201d：闩锁单元201a-201d: latch unit

203a～203d：开关单元203a～203d: switch unit

301：D型触发器301: D-Type Flip-Flop

401：N型晶体管401: N-type transistor

A11、A12、A21、A22：发光单元A11, A12, A21, A22: light emitting unit

D11、D12、D21、D22：驱动电路D11, D12, D21, D22: drive circuit

L11、L12、L21、L22：发光二极管串L11, L12, L21, L22: LED strings

C11、C12、C21、C22：控制信号C11, C12, C21, C22: control signal

A1、A2：控制背光数据A1, A2: control backlight data

B1、B2：触发信号B1, B2: trigger signal

F：画面期间F: during the screen

D：数据接收端D: data receiving end

CK：时钟脉冲输入端CK: clock pulse input

Q：数据输出端Q: data output terminal

Vs：系统电压Vs: system voltage

t1～t8：时间t1～t8: time

S601～S605：本发明一优选实施例的驱动方法流程图各步骤S601～S605: each step of the flow chart of the driving method in a preferred embodiment of the present invention

具体实施方式Detailed ways

图1示出本发明一优选实施例的液晶显示器100的方块图。请参照图1，液晶显示器100包括液晶显示面板101、发光二极管背光模块103、时序控制器105、栅极驱动器107、源极驱动器109，以及背光控制器111。其中，栅极驱动器107与源极驱动器109受控于时序控制器105，用以分别提供扫描信号与显示信号以驱动液晶显示面板101内的像素。FIG. 1 shows a block diagram of aliquid crystal display 100 according to a preferred embodiment of the present invention. Referring to FIG. 1 , theliquid crystal display 100 includes a liquidcrystal display panel 101 , anLED backlight module 103 , atiming controller 105 , agate driver 107 , asource driver 109 , and abacklight controller 111 . Wherein, thegate driver 107 and thesource driver 109 are controlled by thetiming controller 105 to respectively provide scanning signals and display signals to drive the pixels in the liquidcrystal display panel 101 .

于本优选实施例中，发光二极管背光模块103具有4区发光单元A11、A12、A21与A22(但并不限制于此)，每一区发光单元A11、A12、A21与A22皆受控于背光控制器111，用以分别提供光源给对应的液晶显示面板101的像素区域。In this preferred embodiment, theLED backlight module 103 has 4 zones of light emitting units A11, A12, A21 and A22 (but not limited thereto), and each zone of light emitting units A11, A12, A21 and A22 is controlled by the backlight Thecontroller 111 is configured to respectively provide light sources to corresponding pixel regions of the liquidcrystal display panel 101 .

进一步来说，图2示出本发明一优选实施例的发光二极管背光模块103的电路示意图。请合并参照图1与图2，每一区发光单元A11、A12、A21与A22皆具有多颗串接在一起的发光二极管与一个驱动电路。也即：发光单元A11具有多颗串接在一起的发光二极管L11(以下称为发光二极管串L11)以及驱动电路D11。发光单元A12具有多颗串接在一起的发光二极管L12(以下称为发光二极管串L12)以及驱动电路D12。发光单元A21具有多颗串接在一起的发光二极管L21(以下称为发光二极管串L21)以及驱动电路D21。发光单元A22具有多颗串接在一起的发光二极管L22(以下称为发光二极管串L22)以及驱动电路D22。Further, FIG. 2 shows a schematic circuit diagram of anLED backlight module 103 according to a preferred embodiment of the present invention. Please refer to FIG. 1 and FIG. 2 together. Each of the light-emitting units A11 , A12 , A21 and A22 has a plurality of light-emitting diodes connected in series and a driving circuit. That is, the light emitting unit A11 has a plurality of light emitting diodes L11 connected in series (hereinafter referred to as light emitting diode strings L11 ) and a driving circuit D11 . The light emitting unit A12 has a plurality of LEDs L12 connected in series (hereinafter referred to as LED strings L12 ) and a driving circuit D12 . The light emitting unit A21 has a plurality of light emitting diodes L21 connected in series (hereinafter referred to as light emitting diode string L21 ) and a driving circuit D21 . The light emitting unit A22 has a plurality of light emitting diodes L22 connected in series (hereinafter referred to as light emitting diode string L22 ) and a driving circuit D22 .

于本优选实施例中，发光单元A11的驱动电路D11具有闩锁单元201a与开关单元203a。其中，闩锁单元201a用以接收由背光控制器111所提供的控制背光数据A1，并依据背光控制器111所提供的触发信号B1，而于液晶显示器100的一个画面期间(frame period)内对控制背光数据A1进行闩锁，借以输出控制信号C11。开关单元203a耦接闩锁单元201a与发光二极管L11，用以接收闩锁单元201a所输出的控制信号C11，并据以决定发光二极管串L11是否发光。In this preferred embodiment, the driving circuit D11 of the light emitting unit A11 has a latch unit 201a and a switch unit 203a. Wherein, the latch unit 201a is used for receiving the control backlight data A1 provided by thebacklight controller 111, and according to the trigger signal B1 provided by thebacklight controller 111, within a frame period of the liquid crystal display 100 (frame period). Control the backlight data A1 to be latched, so as to output the control signal C11. The switch unit 203a is coupled to the latch unit 201a and the LED L11 for receiving the control signal C11 outputted by the latch unit 201a, and accordingly determining whether the LED string L11 emits light.

发光单元A21的驱动电路D21具有闩锁单元201b与开关单元203b。其中，闩锁单元201b用以接收由背光控制器111所提供的控制背光数据A2，并依据背光控制器111所提供的触发信号B1，而于液晶显示器100的一个画面期间内对控制背光数据A2进行闩锁，借以输出控制信号C21。开关单元203b耦接闩锁单元201b与发光二极管L21，用以接收闩锁单元201b所输出的控制信号C21，并据以决定发光二极管串L21是否发光。The driving circuit D21 of the light emitting unit A21 has a latch unit 201b and aswitch unit 203b. Wherein, the latch unit 201b is used to receive the control backlight data A2 provided by thebacklight controller 111, and according to the trigger signal B1 provided by thebacklight controller 111, control the backlight data A2 within one frame period of theliquid crystal display 100. Latching is performed, whereby the control signal C21 is output. Theswitch unit 203b is coupled to the latch unit 201b and the LED L21, and is used for receiving the control signal C21 output by the latch unit 201b to determine whether the LED string L21 emits light or not.

发光单元A12的驱动电路D12具有闩锁单元201c与开关单元203c。其中，闩锁单元201c用以接收由背光控制器111所提供的控制背光数据A1，并依据背光控制器111所提供的触发信号B2，而于液晶显示器100的一个画面期间内对控制背光数据A1进行闩锁，借以输出控制信号C12。开关单元203c耦接闩锁单元201c与发光二极管L12，用以接收闩锁单元201c所输出的控制信号C12，并据以决定发光二极管串L12是否发光。The driving circuit D12 of the light emitting unit A12 has alatch unit 201c and aswitch unit 203c. Wherein, thelatch unit 201c is used to receive the control backlight data A1 provided by thebacklight controller 111, and according to the trigger signal B2 provided by thebacklight controller 111, to control the backlight data A1 within one frame period of theliquid crystal display 100 Latching is performed, whereby the control signal C12 is output. Theswitch unit 203c is coupled to thelatch unit 201c and the LED L12 to receive the control signal C12 output by thelatch unit 201c, and to determine whether the LED string L12 emits light or not.

发光单元A22的驱动电路D22具有闩锁单元201d与开关单元203d。其中，闩锁单元201d用以接收由背光控制器111所提供的控制背光数据A2，并依据背光控制器111所提供的触发信号B2，而于液晶显示器100的一个画面期间内对控制背光数据A2进行闩锁，借以输出控制信号C22。开关单元203d耦接闩锁单元201d与发光二极管L22，用以接收闩锁单元201d所输出的控制信号C22，并据以决定发光二极管串L22是否发光。The driving circuit D22 of the light emitting unit A22 has alatch unit 201d and aswitch unit 203d. Wherein, thelatch unit 201d is used to receive the control backlight data A2 provided by thebacklight controller 111, and according to the trigger signal B2 provided by thebacklight controller 111, to control the backlight data A2 within one frame period of theliquid crystal display 100 Latching is performed, whereby the control signal C22 is output. Theswitch unit 203d is coupled to thelatch unit 201d and the LED L22 to receive the control signal C22 output by thelatch unit 201d, and to determine whether the LED string L22 emits light or not.

更进一步来说，图3与图4分别示出本发明一优选实施例的闩锁单元201a～201d与开关单元203a～203d的电路图。请合并参照图1～图4，每一闩锁单元201a～201d皆由一个D型触发器301所组成，其数据接收端D用以对应接收由背光控制器111所提供的控制背光数据A1或A2，其时钟脉冲接收端CK用以对应接收由背光控制器111所提供的触发信号B1或B2，而其数据输出端Q则对应输出控制信号C11、C12、C21或C22，在此可了解控制信号C11、C12、C21或C22为驱动发光二极管串L11、L12、L21与L22的PWM信号。Furthermore, FIG. 3 and FIG. 4 respectively show the circuit diagrams of the latch units 201a-201d and the switch units 203a-203d according to a preferred embodiment of the present invention. Please refer to FIGS. 1-4 together. Each of the latch units 201a-201d is composed of a D-type flip-flop 301, and its data receiving end D is used to receive the backlight control data A1 provided by thebacklight controller 111 or A2, its clock pulse receiving terminal CK is used to receive the trigger signal B1 or B2 provided by thebacklight controller 111 correspondingly, and its data output terminal Q is corresponding to the output control signal C11, C12, C21 or C22, here we can understand the control The signals C11 , C12 , C21 or C22 are PWM signals for driving the LED strings L11 , L12 , L21 and L22 .

另外，如图4所示，每一开关单元203a～203d皆由一个N型晶体管401所组成，其栅极用以对应接收由闩锁单元201a～201d所输出的控制信号C11、C12、C21或C22，其第一漏/源极会通过对应的发光二极管串L11、L12、L21或L22耦接至一个系统电压Vs，而其第二漏/源极则耦接至一个接地电位。In addition, as shown in FIG. 4, each switch unit 203a-203d is composed of an N-type transistor 401, and its gate is used to correspondingly receive the control signals C11, C12, C21 or The first drain/source of C22 is coupled to a system voltage Vs through the corresponding LED string L11 , L12 , L21 or L22 , and the second drain/source is coupled to a ground potential.

图5示出本发明一优选实施例的驱动电路D11、D12、D21与D22的操作时序图。图6示出本发明一优选实施例的驱动方法流程图。请合并参照图1～图6，于本优选实施例中，假设每一控制信号C11、C12、C21与C22(也即PWM信号)于液晶显示器100的一个画面期间F的解析度为4位元、控制信号C11的占空比为50％、控制信号C12的占空比为75％、控制信号C21的占空比为25％，而控制信号C22的占空比为25％。FIG. 5 shows an operation timing diagram of the driving circuits D11 , D12 , D21 and D22 according to a preferred embodiment of the present invention. Fig. 6 shows a flowchart of a driving method in a preferred embodiment of the present invention. Please refer to FIGS. 1 to 6 together. In this preferred embodiment, it is assumed that the resolution of each control signal C11, C12, C21 and C22 (that is, the PWM signal) in one frame period F of theliquid crystal display 100 is 4 bits. The duty ratio of the control signal C11 is 50%, the duty ratio of the control signal C12 is 75%, the duty ratio of the control signal C21 is 25%, and the duty ratio of the control signal C22 is 25%.

基于上述假设，由于每一控制信号C11、C12、C21与C22的解析度为4位元，故而每一区发光单元A11、A12、A21与A22内的驱动电路D11、D12、D21与D22于液晶显示器100的一个画面期间F内就需要对应接收4笔控制背光数据A1或A2，也即每一闩锁单元201a～201d依据触发信号B1或B2而于画面期间F内对控制背光数据A1或A2进行闩锁的次数为4次。Based on the above assumptions, since the resolution of each control signal C11, C12, C21 and C22 is 4 bits, the driving circuits D11, D12, D21 and D22 in the light-emitting units A11, A12, A21 and A22 of each region Within one frame period F of thedisplay 100, it is necessary to receive 4 pieces of control backlight data A1 or A2 correspondingly, that is, each latch unit 201a-201d controls the backlight data A1 or A2 within the frame period F according to the trigger signal B1 or B2 The number of times of performing latching is 4 times.

另外，每一闩锁单元201a～201d依据触发信号B1或B2而于画面期间F内对控制背光数据A1或A2进行闩锁结束后会决定出每一控制信号C11、C12、C21与C22的占空比(也即PWM信号的占空比)，借以进一步地决定每一发光二极管串L11、L12、L21与L22的发光亮度。In addition, each latch unit 201a-201d determines the occupation of each control signal C11, C12, C21, and C22 after latching the control backlight data A1 or A2 in the frame period F according to the trigger signal B1 or B2. The duty ratio (that is, the duty ratio of the PWM signal) is used to further determine the luminance of each LED string L11 , L12 , L21 and L22 .

首先解释发光单元A11，闩锁单元201a的D型触发器301的数据接收端D与时钟脉冲接收端CK会分别接收背光控制器111所提供的控制背光数据A1与触发信号B1，如步骤S601，故而于时间t1时，触发信号B1的上升沿会触发闩锁单元201a的D型触发器301，以至于闩锁单元201a的D型触发器301会闩锁处于高电压电平的第1笔控制背光数据A1，如步骤S603，并据以输出控制信号C11以驱动发光二极管串L11，如步骤S605。First explain the light-emitting unit A11, the data receiving terminal D and the clock pulse receiving terminal CK of the D-type flip-flop 301 of the latch unit 201a respectively receive the control backlight data A1 and the trigger signal B1 provided by thebacklight controller 111, as in step S601, Therefore, at time t1, the rising edge of the trigger signal B1 will trigger the D-type flip-flop 301 of the latch unit 201a, so that the D-type flip-flop 301 of the latch unit 201a will latch the first control at a high voltage level. As for the backlight data A1, go to step S603, and output the control signal C11 to drive the LED string L11 accordingly, go to step S605.

紧接着，于时间t3时，触发信号B1的上升沿会再次触发闩锁单元201a的D型触发器301，以至于闩锁单元201a的D型触发器301会闩锁处于高电压电平的第2笔控制背光数据A1，并据以输出控制信号C11以驱动发光二极管串L11。之后，于时间t5时，触发信号B1的上升沿会再次触发闩锁单元201a的D型触发器301，以至于闩锁单元201a的D型触发器301会闩锁处于低电压电平的第3笔控制背光数据A1，并据以输出控制信号C11以驱动发光二极管串L11。最后，于时间t7时，触发信号B1的上升沿会再次触发闩锁单元201a的D型触发器301，以至于闩锁单元201a的D型触发器301会闩锁处于低电压电平的第4笔控制背光数据A1，并据以输出控制信号C11以驱动发光二极管串L11。Then, at time t3, the rising edge of the trigger signal B1 will trigger the D-type flip-flop 301 of the latch unit 201a again, so that the D-type flip-flop 301 of the latch unit 201a will latch the first The two pens control the backlight data A1, and output the control signal C11 to drive the LED string L11 accordingly. Afterwards, at time t5, the rising edge of the trigger signal B1 will trigger the D-type flip-flop 301 of the latch unit 201a again, so that the D-type flip-flop 301 of the latch unit 201a will latch the 3rd voltage level at a low voltage level. The pen controls the backlight data A1, and outputs a control signal C11 accordingly to drive the LED string L11. Finally, at time t7, the rising edge of the trigger signal B1 will trigger the D-type flip-flop 301 of the latch unit 201a again, so that the D-type flip-flop 301 of the latch unit 201a will latch the fourth The pen controls the backlight data A1, and outputs a control signal C11 accordingly to drive the LED string L11.

如此一来，发光单元A11内的驱动电路D11于液晶显示器100的一个画面期间F内会对应接收到4笔控制背光数据A1，借以使得闩锁单元201a的D型触发器301输出占空比为50％的控制信号C11，以控制开关单元203a内的N型晶体管401导通，从而致使发光二极管串L11发光，以提供光源给对应的液晶显示面板101的像素区域。In this way, the driving circuit D11 in the light emitting unit A11 will correspondingly receive four pieces of control backlight data A1 within one frame period F of theliquid crystal display 100, so that the output duty cycle of the D-type flip-flop 301 of the latch unit 201a is 50% of the control signal C11 is used to control the N-type transistor 401 in the switch unit 203 a to turn on, thereby causing the LED string L11 to emit light to provide light to the corresponding pixel area of theLCD panel 101 .

接着解释发光单元A21，闩锁单元201b的D型触发器301的数据接收端D与时钟脉冲接收端CK会分别接收背光控制器111所提供的控制背光数据A2与触发信号B1，如步骤S601，故而于时间t1时，触发信号B1的上升沿会触发闩锁单元201b的D型触发器301，以至于闩锁单元201b的D型触发器301会闩锁处于高电压电平的第1笔控制背光数据A2，如步骤S603，并据以输出控制信号C21以驱动发光二极管串L21，如步骤S605。Then explain the light-emitting unit A21, the data receiving terminal D and the clock pulse receiving terminal CK of the D-type flip-flop 301 of the latch unit 201b respectively receive the control backlight data A2 and the trigger signal B1 provided by thebacklight controller 111, as in step S601, Therefore, at time t1, the rising edge of the trigger signal B1 will trigger the D-type flip-flop 301 of the latch unit 201b, so that the D-type flip-flop 301 of the latch unit 201b will latch the first control at a high voltage level. As for the backlight data A2, go to step S603, and output the control signal C21 to drive the LED string L21 accordingly, go to step S605.

紧接着，于时间t3时，触发信号B1的上升沿会再次触发闩锁单元201b的D型触发器301，以至于闩锁单元201b的D型触发器301会闩锁处于低电压电平的第2笔控制背光数据A2，并据以输出控制信号C21以驱动发光二极管串L21。之后，于时间t5时，触发信号B1的上升沿会再次触发闩锁单元201b的D型触发器301，以至于闩锁单元201b的D型触发器301会闩锁处于低电压电平的第3笔控制背光数据A2，并据以输出控制信号C2以驱动发光二极管串L211。最后，于时间t7时，触发信号B1的上升沿会再次触发闩锁单元201b的D型触发器301，以至于闩锁单元201b的D型触发器301会闩锁处于低电压电平的第4笔控制背光数据A2，并据以输出控制信号C21以驱动发光二极管串L21。Then, at time t3, the rising edge of the trigger signal B1 will trigger the D-type flip-flop 301 of the latch unit 201b again, so that the D-type flip-flop 301 of the latch unit 201b will latch the first The 2 pens control the backlight data A2, and output the control signal C21 to drive the LED string L21 accordingly. Afterwards, at time t5, the rising edge of the trigger signal B1 will trigger the D-type flip-flop 301 of the latch unit 201b again, so that the D-type flip-flop 301 of the latch unit 201b will latch the 3rd voltage level at a low voltage level. The pen controls the backlight data A2, and outputs a control signal C2 to drive the LED string L211 accordingly. Finally, at time t7, the rising edge of the trigger signal B1 will trigger the D-type flip-flop 301 of the latch unit 201b again, so that the D-type flip-flop 301 of the latch unit 201b will latch the fourth The pen controls the backlight data A2, and outputs a control signal C21 accordingly to drive the LED string L21.

如此一来，发光单元A21内的驱动电路D21于液晶显示器100的一个画面期间F内会对应接收到4笔控制背光数据A2，借以使得闩锁单元201b的D型触发器301输出占空比为25％的控制信号C21，以控制开关单元203b内的N型晶体管401导通，从而致使发光二极管串L21发光，以提供光源给对应的液晶显示面板101的像素区域。In this way, the driving circuit D21 in the light emitting unit A21 will correspondingly receive four pieces of control backlight data A2 within one frame period F of theliquid crystal display 100, so that the output duty cycle of the D-type flip-flop 301 of the latch unit 201b is 25% of the control signal C21 to control the N-type transistor 401 in theswitch unit 203b to turn on, thereby causing the LED string L21 to emit light to provide light to the corresponding pixel area of theLCD panel 101 .

紧接着解释发光单元A12，闩锁单元201c的D型触发器301的数据接收端D与时钟脉冲接收端CK会分别接收背光控制器111所提供的控制背光数据A1与触发信号B2，如步骤S601，故而于时间t2时，触发信号B2的上升沿会触发闩锁单元201c的D型触发器301，以至于闩锁单元201c的D型触发器301会闩锁处于高电压电平的第1笔控制背光数据A1，如步骤S603，并据以输出控制信号C12以驱动发光二极管串L12，如步骤S605。Then explain the light-emitting unit A12, the data receiving terminal D and the clock pulse receiving terminal CK of the D-type flip-flop 301 of thelatch unit 201c will respectively receive the control backlight data A1 and the trigger signal B2 provided by thebacklight controller 111, as in step S601 , so at time t2, the rising edge of the trigger signal B2 will trigger the D-type flip-flop 301 of thelatch unit 201c, so that the D-type flip-flop 301 of thelatch unit 201c will latch the first pen at a high voltage level Control the backlight data A1, as in step S603, and output the control signal C12 to drive the LED string L12 accordingly, as in step S605.

紧接着，于时间t4时，触发信号B2的上升沿会再次触发闩锁单元201c的D型触发器301，以至于闩锁单元201c的D型触发器301会闩锁处于高电压电平的第2笔控制背光数据A1，并据以输出控制信号C12以驱动发光二极管串L12。之后，于时间t6时，触发信号B2的上升沿会再次触发闩锁单元201c的D型触发器301，以至于闩锁单元201c的D型触发器301会闩锁处于高电压电平的第3笔控制背光数据A1，并据以输出控制信号C12以驱动发光二极管串L12。最后，于时间t8时，触发信号B2的上升沿会再次触发闩锁单元201c的D型触发器301，以至于闩锁单元201c的D型触发器301会闩锁处于低电压电平的第4笔控制背光数据A1，并据以输出控制信号C12以驱动发光二极管串L12。Then, at time t4, the rising edge of the trigger signal B2 will trigger the D-type flip-flop 301 of thelatch unit 201c again, so that the D-type flip-flop 301 of thelatch unit 201c will latch the first The two pens control the backlight data A1, and output the control signal C12 to drive the LED string L12 accordingly. Afterwards, at time t6, the rising edge of the trigger signal B2 will trigger the D-type flip-flop 301 of thelatch unit 201c again, so that the D-type flip-flop 301 of thelatch unit 201c will latch the 3rd voltage at the high voltage level. The pen controls the backlight data A1, and outputs a control signal C12 to drive the LED string L12 accordingly. Finally, at time t8, the rising edge of the trigger signal B2 will trigger the D-type flip-flop 301 of thelatch unit 201c again, so that the D-type flip-flop 301 of thelatch unit 201c will latch the fourth The pen controls the backlight data A1, and outputs a control signal C12 to drive the LED string L12 accordingly.

如此一来，发光单元A12内的驱动电路D12于液晶显示器100的一个画面期间F内会对应接收到4笔控制背光数据A1，借以使得闩锁单元201c的D型触发器301输出占空比为75％的控制信号C12，以控制开关单元203c内的N型晶体管401导通，从而致使发光二极管串L12发光，以提供光源给对应的液晶显示面板101的像素区域。In this way, the driving circuit D12 in the light-emitting unit A12 will correspondingly receive four pieces of control backlight data A1 within one frame period F of theliquid crystal display 100, so that the output duty cycle of the D-type flip-flop 301 of thelatch unit 201c is 75% of the control signal C12 is used to control the N-type transistor 401 in theswitch unit 203 c to turn on, thereby causing the LED string L12 to emit light to provide light to the corresponding pixel area of theLCD panel 101 .

最后解释发光单元A22，闩锁单元201d的D型触发器301的数据接收端D与时钟脉冲接收端CK会分别接收背光控制器111所提供的控制背光数据A2与触发信号B2，如步骤S601，故而于时间t2时，触发信号B2的上升沿会触发闩锁单元201d的D型触发器301，以至于闩锁单元201d的D型触发器301会闩锁处于高电压电平的第1笔控制背光数据A2，如步骤S603，并据以输出控制信号C22以驱动发光二极管串L22，如步骤S605。Finally, explain the light-emitting unit A22, the data receiving terminal D and the clock pulse receiving terminal CK of the D-type flip-flop 301 of thelatch unit 201d respectively receive the control backlight data A2 and the trigger signal B2 provided by thebacklight controller 111, as in step S601, Therefore, at time t2, the rising edge of the trigger signal B2 will trigger the D-type flip-flop 301 of thelatch unit 201d, so that the D-type flip-flop 301 of thelatch unit 201d will latch the first control at a high voltage level. As for the backlight data A2, go to step S603, and output the control signal C22 to drive the LED string L22 accordingly, go to step S605.

紧接着，于时间t4时，触发信号B2的上升沿会再次触发闩锁单元201d的D型触发器301，以至于闩锁单元201d的D型触发器301会闩锁处于低电压电平的第2笔控制背光数据A2，并据以输出控制信号C22以驱动发光二极管串L22。之后，于时间t6时，触发信号B2的上升沿会再次触发闩锁单元201d的D型触发器301，以至于闩锁单元201d的D型触发器301会闩锁处于低电压电平的第3笔控制背光数据A2，并据以输出控制信号C22以驱动发光二极管串L22。最后，于时间t8时，触发信号B2的上升沿会再次触发闩锁单元201d的D型触发器301，以至于闩锁单元201d的D型触发器301会闩锁处于低电压电平的第4笔控制背光数据A2，并据以输出控制信号C22以驱动发光二极管串L22。Then, at time t4, the rising edge of the trigger signal B2 will trigger the D-type flip-flop 301 of thelatch unit 201d again, so that the D-type flip-flop 301 of thelatch unit 201d will latch the first The two pens control the backlight data A2, and output the control signal C22 to drive the LED string L22 accordingly. Afterwards, at time t6, the rising edge of the trigger signal B2 will trigger the D-type flip-flop 301 of thelatch unit 201d again, so that the D-type flip-flop 301 of thelatch unit 201d will latch the 3rd voltage at a low voltage level. The pen controls the backlight data A2, and outputs a control signal C22 to drive the LED string L22 accordingly. Finally, at time t8, the rising edge of the trigger signal B2 will trigger the D-type flip-flop 301 of thelatch unit 201d again, so that the D-type flip-flop 301 of thelatch unit 201d will latch the fourth The pen controls the backlight data A2, and outputs a control signal C22 to drive the LED string L22 accordingly.

如此一来，发光单元A22内的驱动电路D22于液晶显示器100的一个画面期间F内会对应接收到4笔控制背光数据A2，借以使得闩锁单元201d的D型触发器301输出占空比为25％的控制信号C22，以控制开关单元203d内的N型晶体管401导通，从而致使发光二极管串L22发光，以提供光源给对应的液晶显示面板101的像素区域。In this way, the driving circuit D22 in the light emitting unit A22 will correspondingly receive four pieces of control backlight data A2 within one frame period F of theliquid crystal display 100, so that the output duty cycle of the D-type flip-flop 301 of thelatch unit 201d is 25% of the control signal C22 to control the N-type transistor 401 in theswitch unit 203d to turn on, thereby causing the LED string L22 to emit light to provide light to the corresponding pixel area of theLCD panel 101 .

于本优选实施例中，同一行的驱动电路会接收相同的控制背光数据，也即：驱动电路D11与D12会同时接收控制背光数据A1，而驱动电路D21与D22会同时接收控制背光数据A2。除此之外，同一列的驱动电路会接收相同的触发信号，也即：驱动电路D11与D21会同时接收触发信号B1，而驱动电路D12与D22会同时接收触发信号B2。如此一来，诸如接收触发信号B1或B2的控制线就可以同时控制同一列的发光单元的所有发光二极管串，以至于本优选实施例与现有技术相比可以大量减少传输线与传输时间。In this preferred embodiment, the driving circuits in the same row receive the same control backlight data, that is, the driving circuits D11 and D12 simultaneously receive the control backlight data A1, and the driving circuits D21 and D22 simultaneously receive the control backlight data A2. In addition, the driving circuits in the same row receive the same trigger signal, that is, the driving circuits D11 and D21 receive the trigger signal B1 at the same time, and the driving circuits D12 and D22 receive the trigger signal B2 at the same time. In this way, for example, the control line receiving the trigger signal B1 or B2 can simultaneously control all the LED strings of the light-emitting units in the same column, so that this preferred embodiment can greatly reduce the transmission lines and transmission time compared with the prior art.

另外，本优选实施例可以依实际设计需求来改变每一控制信号C11、C12、C21与C22(也即PWM信号)于一个画面期间F的解析度位元数，并且可以适应性地改变由背光控制器111所提供的控制背光数据A1与A2后，即可增加PWM的控制方式的弹性。再者，由于本优选实施例采用定电压控制的方式，故而并不需于每个分区控制的区域中使用电流控制器，借以来大大地将低制作成本。In addition, this preferred embodiment can change the number of resolution bits of each control signal C11, C12, C21, and C22 (that is, the PWM signal) in a frame period F according to actual design requirements, and can adaptively change the number of bits controlled by the backlight. After the backlight control data A1 and A2 provided by thecontroller 111 , the flexibility of the PWM control method can be increased. Furthermore, since this preferred embodiment adopts a constant voltage control method, it is not necessary to use a current controller in each zone controlled area, thereby greatly reducing the manufacturing cost.

然而，在本发明的其他优选实施例中，每一闩锁单元201a～201d依据触发信号B1或B2而于画面期间F内对控制背光数据A1或A2进行闩锁的次数也可由控制背光数据A1或A2决定。更清楚来说，背光控制器111可以先行分析/判断控制背光数据A1或A2的改变程度来适应性地决定是否提供触发信号B1或B2给驱动电路D11、D12、D21与D22。However, in other preferred embodiments of the present invention, the number of times each latch unit 201a-201d latches the control backlight data A1 or A2 within the frame period F according to the trigger signal B1 or B2 can also be determined by the control backlight data A1 or A2 decision. To be clearer, thebacklight controller 111 can first analyze/judgment the change degree of the control backlight data A1 or A2 to adaptively decide whether to provide the trigger signal B1 or B2 to the driving circuits D11 , D12 , D21 and D22 .

举例来说，由于驱动电路D12的闩锁单元201c于时间t2、t4与t6皆为闩锁并输出处于高电压电平的控制背光数据A1。如此一来，背光控制器111即可在提供触发信号B2给驱动电路D12的闩锁单元201c前，先行分析/判断出控制背光数据A1并未改变，故而在时间t4与t6时，就不再提供触发信号B2给驱动电路D12的闩锁单元201c。也因如此，即可减少功率消耗。For example, since thelatch unit 201c of the driving circuit D12 is latched at times t2, t4 and t6 and outputs the control backlight data A1 at a high voltage level. In this way, before thebacklight controller 111 provides the trigger signal B2 to thelatch unit 201c of the driving circuit D12, it can first analyze/judge that the control backlight data A1 has not changed, so at time t4 and t6, no longer The trigger signal B2 is provided to thelatch unit 201c of the driving circuit D12. Also because of this, power consumption can be reduced.

虽然上述优选实施例以4区发光单元A11、A12、A21与A22搭配控制信号C11、C12、C21与C22于液晶显示器100的一个画面期间F的解析度为4位元，且控制信号C11的占空比为50％、控制信号C12的占空比为75％、控制信号C21的占空比为25％，而控制信号C22的占空比为25％的例子来做说明，但以本领域的技术人员应当可以在参照完上述优选实施例的解说后，而自行且轻易地推演/类推出更多区发光单元搭配其于设定条件下的实施方式，故而在此并不再加以赘述。Although the above-mentioned preferred embodiment uses the 4-zone light-emitting units A11, A12, A21 and A22 to cooperate with the control signals C11, C12, C21 and C22, the resolution of one frame period F of theliquid crystal display 100 is 4 bits, and the control signal C11 occupies The duty ratio is 50%, the duty ratio of the control signal C12 is 75%, the duty ratio of the control signal C21 is 25%, and the duty ratio of the control signal C22 is 25%. After referring to the description of the above-mentioned preferred embodiment, the skilled person should be able to easily deduce/analogize the implementation manners of the matching of the light-emitting units in more regions under the set conditions, so no further description is given here.

另外，在上述优选实施例中利用背光控制器111提供控制背光数据A1与A2以及触发信号B1与B2给驱动电路D11、D12、D21与D22。然而，在本发明其他优选实施例中，也可直接通过/利用时序控制器105来提供控制背光数据A1与A2以及触发信号B1与B2给驱动电路D11、D12、D21与D22，但是皆不限制于此。In addition, in the above-mentioned preferred embodiment, thebacklight controller 111 is used to provide control backlight data A1 and A2 and trigger signals B1 and B2 to the driving circuits D11 , D12 , D21 and D22 . However, in other preferred embodiments of the present invention, the backlight control data A1 and A2 and trigger signals B1 and B2 can also be provided directly to the driving circuits D11, D12, D21 and D22 through/using thetiming controller 105, but there is no limitation here.

综上所述，本发明将驱动发光二极管背光模块的每一分区控制的区域内所需的驱动电路排列成矩阵结构，并且以快速扫描的方式来提供触发信号以控制每一区发光单元的发光二极管串，如此设计方式即可以大量减少传输线与传输时间。另外，由于每一驱动电路内又具有闩锁单元以对控制背光数据进行闩锁，所以在快速扫描以提供触发信号来控制每一区发光单元的发光二极管串的同时，并不让每一区发光单元的发光二极管串亮度降低或发生闪烁。To sum up, the present invention arranges the driving circuits required to drive the LED backlight module in each area controlled by each area into a matrix structure, and provides trigger signals in a fast scanning manner to control the light emission of the light-emitting units in each area. Diode strings, such a design can greatly reduce the transmission line and transmission time. In addition, because there is a latch unit in each driving circuit to latch the control backlight data, so while fast scanning is used to provide a trigger signal to control the light-emitting diode strings of the light-emitting units in each region, each region does not The brightness of the light emitting diode strings of the light emitting unit decreases or flickers.

除此之外，由于每一驱动电路是以定电压控制的方式来驱动每一区发光单元的发光二极管串，所以每个分区控制的区域中并不需使用电流控制器，如此一来即可大大地将低制作成本。再者，每一驱动电路的闩锁单元可依实际设计需求来改变其所输出的控制信号于一个画面期间的解析度位元数，如此再适应性地改变由背光控制器或时序控制器所提供的控制背光数据后，即可大幅地增加PWM的控制方式的弹性。In addition, because each driving circuit drives the light-emitting diode strings of the light-emitting units in each area in a constant voltage control mode, there is no need to use a current controller in the area controlled by each area, so that Greatly lower production costs. Furthermore, the latch unit of each driving circuit can change the number of resolution bits of the control signal output by it during a frame according to the actual design requirements, so as to adaptively change the number of bits set by the backlight controller or the timing controller. After the backlight control data is provided, the flexibility of the PWM control method can be greatly increased.

虽然本发明已以多个实施例公开如上，然其并非用以限定本发明，任何所属技术领域中的普通技术人员，在不脱离本发明的精神和范围内，当可作些许的更动与润饰，因此本发明的保护范围当视所附的权利要求所界定的范围为准。Although the present invention has been disclosed above with a number of embodiments, it is not intended to limit the present invention. Any person skilled in the art may make some modifications and changes without departing from the spirit and scope of the present invention. modification, so the scope of protection of the present invention should be determined by the scope defined by the appended claims.

Claims (18)

1. driving circuit; Be suitable for driving the light emitting diode at least four district's luminescence units in the light-emitting diode (LED) backlight module of a LCD; Wherein all have a plurality of these light emitting diodes that are serially connected in each district's luminescence unit; And wherein, drive that required said driving circuit is arranged in matrix structure in the zone of each subregion control of said light-emitting diode (LED) backlight module, receive identical control backlight data with the said driving circuit of delegation; The said driving circuit of same row receives the identical triggering signal, and said driving circuit comprises:

One latch lock unit in order to receiving said control backlight data, and carries out breech lock to this control backlight data according to said trigger pip in during a picture, so as to exporting a control signal; And

One switch element couples this latch lock unit and this light emitting diode, in order to receiving this control signal, and determines according to this whether this light emitting diode is luminous.

2. driving circuit as claimed in claim 1, wherein this latch lock unit comprises:

One D flip-flop, its data input pin should be controlled backlight data in order to receive, and its clock pulse input terminal is in order to receive this trigger pip, and its data output end is then in order to export this control signal.

3. driving circuit as claimed in claim 1, wherein this switch element comprises:

One N transistor npn npn, its grid is in order to receive this control signal, and its first leakage/source electrode is coupled to a system voltage through this light emitting diode, and its second leakage/source electrode then is coupled to an earthing potential.

4. driving circuit as claimed in claim 3, wherein when this N transistor npn npn conducting, this light emitting diode can be luminous, otherwise then not luminous.

5. driving circuit as claimed in claim 1; Wherein this LCD also comprises time schedule controller; And this light-emitting diode (LED) backlight module also comprises a backlight controller; And one of them couples this driving circuit this time schedule controller and this backlight controller, in order to this control backlight data and this trigger pip to be provided.

6. driving circuit as claimed in claim 1, wherein this control signal is a pulse width modulating signal.

7. a light-emitting diode (LED) backlight module is suitable for a LCD, and this light-emitting diode (LED) backlight module comprises:

At least four district's luminescence units all have a plurality of light emitting diodes that are serially connected in each district's luminescence unit; And

At least 4 wheel driven moves circuit; In order to drive this light emitting diode; Wherein, drive that required said driving circuit is arranged in matrix structure in the zone of each subregion control of said light-emitting diode (LED) backlight module, receive identical control backlight data with the said driving circuit of delegation; The said driving circuit of same row receives the identical triggering signal, and said driving circuit comprises:

One latch lock unit in order to receiving said control backlight data, and carries out breech lock to this control backlight data according to said trigger pip in during a picture, so as to exporting a control signal; And

One switch element couples this latch lock unit and this light emitting diode, in order to receiving this control signal, and determines according to this whether this light emitting diode is luminous.

8. light-emitting diode (LED) backlight module as claimed in claim 7, wherein this latch lock unit comprises:

One D flip-flop, its data input pin should be controlled backlight data in order to receive, and its clock pulse input terminal is in order to receive this trigger pip, and its data output end is then in order to export this control signal.

9. light-emitting diode (LED) backlight module as claimed in claim 7 is put, and wherein this switch element comprises:

One N transistor npn npn, its grid is in order to receive this control signal, and its first leakage/source electrode is coupled to a system voltage through this light emitting diode, and its second leakage/source electrode then is coupled to an earthing potential.

10. light-emitting diode (LED) backlight module as claimed in claim 9, wherein when this N transistor npn npn conducting, this light emitting diode can be luminous, otherwise then not luminous.

11. light-emitting diode (LED) backlight module as claimed in claim 7 also comprises:

One backlight controller couples this driving circuit, in order to this control backlight data and this trigger pip to be provided.

12. light-emitting diode (LED) backlight module as claimed in claim 7, wherein this LCD comprises time schedule controller, couples this driving circuit, in order to this control backlight data and this trigger pip to be provided.

13. driving circuit as claimed in claim 7, wherein this control signal is a pulse width modulating signal.

14. driving method; Be suitable for driving the light emitting diode at least four district's luminescence units in the light-emitting diode (LED) backlight module; Wherein all have a plurality of these light emitting diodes that are serially connected in each district's luminescence unit; And wherein, drive that required said driving circuit is arranged in matrix structure in the zone of each subregion control of said light-emitting diode (LED) backlight module, receive identical control backlight data with the said driving circuit of delegation; The said driving circuit of same row receives the identical triggering signal, and this driving method comprises:

Said control backlight data and said trigger pip are provided;

During a picture this control backlight data is carried out breech lock according to this trigger pip, so as to exporting a control signal; And

According to this control signal to drive this light emitting diode.

15. driving method as claimed in claim 14, the number of times that wherein in during this picture this control backlight data is carried out breech lock according to this trigger pip by the resolution bit number of said control signal during a said picture maybe this control backlight data determine.

16. driving method as claimed in claim 14 wherein carries out can determining after breech lock finishes the dutycycle of this control signal to this control backlight data in during this picture according to this trigger pip.

17. driving method as claimed in claim 16, the wherein brightness of this lumination of light emitting diode of the dutycycle of this control signal decision.

18. driving method as claimed in claim 14, wherein this control signal is a pulse width modulating signal.

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