Liquid crystal display device and overcurrent protection circuit thereof

Abstract

The invention discloses an overcurrent protection circuit of a liquid crystal display device. The overcurrent protection circuit comprises an electrical level converter, a GOA (Gate Driver On Array) circuit, a protection triggering module and a plurality of voltage comparison modules, wherein a plurality of paths of clock signals are output by the electrical level converter and are provided for the GOA circuit; one voltage comparison module is connected between any two adjacent paths of the clock signals; an output end of each voltage comparison module is connected to the protection triggering module, wherein each voltage comparison module comprises a first comparison module and a second comparison module, and each first comparison module is used for comparing current values of two adjacent paths of the clock signals and outputting a first voltage difference value; each second comparison module is used for comparing reference voltage with an absolute value of the first voltage difference value and then outputting a second voltage difference value; the protection triggering module is used for judging the size of the second voltage difference value; if the second voltage difference value is more than zero, the protection triggering module sends out a control signal to the electrical level converter and the electrical level converter is switched off. The invention further discloses the liquid crystal display device comprising the overcurrent protection circuit.

Description

technical field [0001] The invention relates to the technical field of display devices, in particular to a liquid crystal display device and an overcurrent protection circuit thereof. Background technique [0002] Active Matrix Liquid Crystal Display (AMLCD) is currently the most commonly used display device, the active matrix liquid crystal display includes a plurality of pixels, each pixel has a thin film transistor (Thin Film Transistor, TFT), the The gate of the TFT is connected to the scanning line extending in the horizontal direction, the drain of the TFT is connected to the data line extending in the vertical direction, and the source of the TFT is connected to the corresponding pixel electrode. If enough positive voltage is applied to a scanning line in the horizontal direction, all TFTs connected to the scanning line will be turned on, and the data signal voltage loaded on the data line will be written into the pixel electrode, thereby displaying the picture . ...

AI Technical Summary

Problems solved by technology

[0006] However, since the clock signal CK 1 ~CK 4 When the voltage is switched between high and low levels, the corresponding current signal will generate a large spike current. Therefore, it is difficult to set the reference current value in the protection circuit. If the reference current value is set too small, it will cause errors. trigger, which will cause the LCD display to stop working; if the set reference current value is too large, the protection action may not be triggered when an abnormality occurs

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