Unlock instant, AI-driven research and patent intelligence for your innovation.

led backlight and liquid crystal display device

A technology of LED backlight source and liquid crystal display device, which is applied to static indicators, instruments, etc., can solve the problems that LED backlight source cannot provide display light source and affect the display of liquid crystal display device, etc.

Active Publication Date: 2016-02-10
TCL CHINA STAR OPTOELECTRONICS TECH CO LTD
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

When the backlight driving integrated circuit 130 detects that the negative terminal voltage of a plurality of LEDs in the arbitrary LED string is zero, the backlight driving integrated circuit 130 will control all other LED strings except the arbitrary LED string to be turned off, so that the multiple LED strings 120 are all extinguished, thereby making the LED backlight unable to provide display light source to the liquid crystal display panel, affecting the display of the liquid crystal display device.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • led backlight and liquid crystal display device
  • led backlight and liquid crystal display device
  • led backlight and liquid crystal display device

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0024] figure 2 A circuit diagram of an LED backlight source for a liquid crystal display device according to Embodiment 1 of the present invention is shown.

[0025] like figure 2 As shown, according to Embodiment 1 of the present invention, the LED backlight for the liquid crystal display device is set opposite to the liquid crystal display panel, and the LED backlight provides a display light source to the liquid crystal display panel, so that the liquid crystal display panel displays images, and the LED backlight The source includes a boost circuit 210, N LED strings A connected in parallel 1 ,...,A n , a backlight driving integrated circuit 220 and N control circuits 230, wherein, N is an integer greater than zero.

[0026] The boost circuit 210 is used to boost the input DC voltage Vin and output the boosted DC voltage.

[0027] N LED strings A 1 ,...,A n Used to provide a display light source to the liquid crystal display panel, each LED string includes a plural...

Embodiment 2

[0047] In Embodiment 2, in order to avoid unnecessary repetition, only the differences between Embodiment 2 and Embodiment 1 are described.

[0048] image 3 A circuit diagram of an LED backlight source for a liquid crystal display device according to Embodiment 2 of the present invention is shown.

[0049] like image 3 As shown, in each control circuit of the LED backlight according to Embodiment 2 of the present invention, the open circuit detection unit 331 includes an operational amplifier OP2, and the open circuit trigger protection unit 332 includes a MOS transistor Q3.

[0050] In each control circuit, the positive terminal of the operational amplifier OP2 is grounded, the output terminal of the operational amplifier OP2 is connected to the gate of the MOS transistor Q3, and the drain of the MOS transistor Q3 is connected to the drain of the MOS transistor Q1 in the first LED string.

[0051] where, in the first control circuit B 1 , the negative terminal of the ope...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

An LED backlight source comprises: a boosting circuit (210), for boosting an input direct current voltage and outputting a boosted direct current voltage; N LED strings (Α1…, An) connected in parallel, each LED string comprising multiple LEDs connected in series and receiving the boosted direct current voltage from the boosting circuit (210); a backlight drive integrated circuit (220), for controlling connection / disconnection of the boosting circuit (210) and determining, according to whether the voltage of a negative terminal of any LED string is equal to 0, whether to turn off other LED strings than the LED string; and N control circuits (230), each controlling the voltage of a negative terminal of a corresponding LED string not to be equal to 0, so that the backlight drive integrated circuit (220) cannot turn off other LED strings than the LED string. When any LED string is disconnected, the backlight drive integrated circuit (220) cannot turn off other LED strings than the LED string; in this way, the N LED strings (Α1…, An) are all avoided from being turned off, and the LED backlight source can continuously provide a display light source. In addition, also provided is a liquid crystal display device having the LED backlight source.

Description

technical field [0001] The invention relates to the field of liquid crystal display. Specifically, it relates to an LED backlight source and a liquid crystal display device. Background technique [0002] With the continuous advancement of technology, the backlight technology of the liquid crystal display device has been continuously developed. Conventional liquid crystal display devices use cold cathode fluorescent lamps (CCFLs) as backlight sources. However, due to the shortcomings of CCFL backlight such as poor color reproduction ability, low luminous efficiency, high discharge voltage, poor discharge characteristics at low temperature, and long time for heating to reach a stable gray level, backlight technology using LED backlight has been developed. [0003] In the liquid crystal display device, the LED backlight is arranged opposite to the liquid crystal display panel, so that the LED backlight provides a display light source to the liquid crystal display panel, where...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): G09G3/34G09G3/36
CPCG09G3/3406
Inventor 曹丹
Owner TCL CHINA STAR OPTOELECTRONICS TECH CO LTD