I was working on a Hisense LCD TV model TLM40V68PK, with the motherboard number RSAG7.820.4154-ROH VER B. After checking the board, I found that the N17 small patch three-terminal regulator, SE8117TA (940-LF), had an input voltage of 5V that remained stable, but the output voltage was fluctuating between 1.01V and 1.13V. When the voltage stabilized at 1.23V, the TV worked properly again. I wasn't sure what could be used as a replacement for the SE8117TA (940-LF). After doing some research online, I found that the APL1117 could be a suitable alternative. It supports various output voltages like 1.8V, 2.5V, 2.85V, and 3.3V, with 3.3V being fixed if it's not marked. If it has an ADJ option, you can adjust the output accordingly.
I decided to try replacing the SE8117TA (940-LF) with an APL1117 with ADJ. After installation, the output voltage stabilized at 1.2V, and the TV functioned normally. This fix resolved the issue successfully. It was a bit tricky, but the replacement worked perfectly. I'm glad I could figure this out without having to replace the entire motherboard.
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