Overcurrent protection method and overcurrent protection system of liquid crystal display panel

Abstract

The invention provides an overcurrent protection method and an overcurrent protection system of a liquid crystal display panel. The method comprises steps of carrying out current sampling for many times on driving current output by a power supply management chip according to a fixed sampling period in an overcurrent protection period so as to acquire multiple current sampling values; by accumulating difference values of the current sampling values and a preset overcurrent threshold so as to obtain an accumulated overcurrent value; judging whether the accumulated overcurrent value exceeds a preset accumulated overcurrent threshold; and starting overcurrent protection when the accumulated overcurrent value exceeds the preset accumulated overcurrent threshold. According to the invention, accuracy and timeliness of overcurrent judgment can be improved; and under the precise that the liquid crystal display panel is effectively protected, the OCP is prevented from frequently being started.

Description

technical field [0001] The invention relates to the field of display technology, in particular to an overcurrent protection method and an overcurrent protection system for a liquid crystal display panel. Background technique [0002] Liquid Crystal Display (LCD) has many advantages such as thin body, power saving, and no radiation, and has been widely used, such as: LCD TV, mobile phone, personal digital assistant (PDA), digital camera, computer screen or Laptop screens, etc., dominate the field of flat panel displays. [0003] Most of the liquid crystal displays currently on the market are backlight liquid crystal displays, which include a liquid crystal display panel and a backlight module (Backlight Module). The working principle of the liquid crystal display panel is to pour liquid crystal molecules between the thin film transistor array substrate (ThinFilm Transistor Array Substrate, TFT Array Substrate) and the color filter substrate (ColorFilter, CF), and apply a dri...

AI Technical Summary

Problems solved by technology

[0004] In the field of smart TVs, the large-size LCD has become a trend, and people's demand for its size has increased from the previous mainstream 32 inches to 55 inches or even larger, because large-size LCDs have a better visual experience, but This also brings some problems: the size of the liquid crystal display increases, and the power consumption also increases. Due to the differentiation of electronic devices, the power module may have overcurrent and short circuit, resulting in overheating and damage to the liquid crystal display panel.

[0005] In order to prevent the liquid crystal display from overcurrent, causing the liquid crystal display panel to be overheated and damaged, it is necessary to add over current protection (Over Current Protection, OCP) to the driving system of the liquid crystal display. A commonly used OCP method is: in the timing controller (TCON) Set an over-current threshold, and continuously detect the real-time current of the power management chip (Powermanage IC, PMIC) through the timing controller. When the detected current exceeds the over-current threshold, start the OCP, switch the power output, and prevent the liquid crystal display panel from Overheating and burning, this method mainly detects the instantaneous current of the PMIC. If the over-current threshold is set too low, it will cause OCP to start frequently; if the over-current threshold is set too high, it is easy for the LCD panel to work below the current threshold. Continued heat, causing damage to the LCD panel

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