Xinke TDV4-4621 LCD TV integrated fault repair - Home Appliances

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South China only ushered in the official late autumn in the past few days, the weather was cool, and the farewell to the heat, the mood was very good. In the afternoon, I wanted to go hiking with my friends on the outskirts of the city. But a damn call shattered my plan. The LCD of the leader of the ruling party broke down and asked me to help.
Model: Shinco TDV-4621, LCD color TV failure phenomenon with DVD: There is about 3CM wide green belt interference band on the left side of the screen. The image also has a green brushed negative phase at the dark level, without accompanying sound.
Overhaul process: First distinguish whether it is power supply interference or digital board. Switch the screen to AV state, the blue screen is full of green screen interference points. According to experience, the interference should be caused by the power circuit.
Disassemble the back cover and visually see that there are three capacitors "pregnancy", two of which are +12V filter, the other one is +5.7V filter, quick change, boot, the image is gorgeous, the first fault is quickly eliminated.
Silent faults first judge whether it is a channel or a power amplifier. Use the DVD that comes with the unit to play, let the volume turn to 100, and still "silence is gold." Uh... It seems that the silent fault comes from the power amplifier circuit.
The power amplifier circuit is a small 48-pin SMD IC, the model is TPA3008D2, the pin-tight circuit is small and double-sided soldered, and there is no such IC data at hand. It is not easy to overhaul. After all the hardships, I finally found the IC data, checked the IC's various working points, the voltage is all normal, but it is silent, suspected IC damage, where can I come to IC? So take a closer look at the information and make a decision.
From the data, the first foot is a mute function. It is controlled by a triode. The “mute” and normal B-pole voltages are not changed by the remote control. Where can the small line be able to find the CPU lead? Holding the try to mind, the mute triode is removed and turned on, just like the stone and Li Yugang singing "I am a little stone..." Very nice! The user's son said, "Uncle, you are too hard! (Tide words say 'You are too powerful.') Afterwards, I realized that they had asked the famous XXX electrical maintenance shop in the city to see it. After the dismantling of the machine, the judge must change. Digital board, about 850 yuan, but the machine is a DVD-connected motherboard, can not buy, and the city has no new service points, so the abortion.
It’s all joyful to fix it, anyway, it’s lower than the price of 850, win-win! Haha!
Xiucai's message: Some faults that can be modified are not necessary to stick to the rules. If you want to replace the IC, you may not be able to solve the problem, and the machine can't get it. You think about it, gently solder the silent tube, and immediately! Why not do it?
Send the TPA3008D2 information I downloaded, this IC has a lot of LCDs, maybe it will be useful to you in the future? Thank you!