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Brief analysis of common faults of high pressure plate in liquid crystal display

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Integrity of a liquid crystal display general by the LCD screen, motherboard, key board and high-pressure plate (also known as rise plate) and other parts, and LCD screen and the screen of liquid crystal particles, glass, signal processing board and a lamp tube; wherein. Liquid crystal display, on the one hand, on the motherboard provides the signal the LCD screen signal processing board decoding sent to LCD screen particle, promote liquid crystal particles flip, then is not to see the bright picture, because there is no back lamp (that is, paste in liquid crystal around at the back, the above said lamp) light, background only a dark image. On the other hand, the main board generated signals, and immediately began to work to boost the board, and promote the fluorescent lamp, and in the light of the back lamp, liquid crystal display in order to display the complete image. Visible, the role of the high pressure plate is to light the lamp. Below we have a brief analysis of several common faults of high pressure plate:

1, instant bright immediately black the mainly circuit play due to the feedback pressure plate, such as: high pressure is too high to protect, feedback circuit problems due to the feedback voltage, the feedback current is too large, a lamp tube pin loose off, IC output is too high will cause the problem, principle as long as the IC is normal output, self-excited oscillation, other any parts bad will lead to the problem, the phenomenon is bad LCD boosted in the most common phenomenon.  
2, the power indicator light but no display this problem mainly boost circuit board without the formation of a high pressure lead to, such as: 12V did not join or voltage is not normal, control voltage did not join, grounding is not normal, IC non oscillatory / no output, self-excited oscillation circuit generates bad will appear the phenomenon.  
3, three if due to rise plate that is causing the problem, is most are to lead to boost circuit board, are generally easy to measure, such as: 12V, self-excited tube breakdown, IC breakdown will lead to; also: power supply part or boost circuit board with a board (i.e., even in a) machine, no power output or abnormal etc. will also produce the phenomenon.  
4, brightness partial dark boost in brightness control lines are not normal, 12V low, low output IC, high voltage circuit abnormal will cause the problem. Part may be accompanied by heating after tens of seconds protection, no display.  
, 5 power indicator light flashes the problem with three phenomenon almost, the majority of the pipe leads to the breakdown. 6, interference mainly water wave interference, the screen jitter / beating, (the phenomenon is relatively small. Most of them are LCD screen) the star shone, mainly high voltage transmission line.