Previously, I posted a help request regarding an LCD screen that had stripes. I suspected it was related to the screen cable or capacitor leakage. Therefore, I purchased a ribbon cable and driver board from Taobao, but the problem persisted. It seems the issue lies with the logic board. I wanted to check the VGH, VGL, and other voltages, but I didn’t have the schematics, and there were no markings on the logic board. The problem occurs after about 10 minutes, which led me to suspect capacitor leakage. I took out a regulated power supply set to 3.3V and 1.5A and applied it to the surface-mounted capacitor near the ribbon cable connector. After waiting for 1-2 minutes, I touched the capacitors on the logic board, and surprisingly, none of them were hot. However, one chip was hot. Upon closer inspection, it was the AAT1176B in a QFN package, so I bought a replacement. I was quite careless during the replacement; after using a hot air gun, I didn’t use a temperature-controlled soldering iron and removed the solder from the four sides with a regular soldering iron. The temperature might have been too high, causing two pads to come off on one side. I thought it was a failure, but after assembling it and waiting for half an hour, the image was normal, and there were no stripes. I really got lucky!
Original source: http://www.jdwx.info/thread-721148-1-1.html
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