Hello everyone. I'm a little bit puzzled at the moment and was wondering if someone had any ideas.
I can follow the adapter voltage all the way to PQ52. PQ52 is off because ACOK# is at 5 Volts. That drew my attention to the ISL6251A . ACSET (pin 2) is at 0 V, so that explains it. But I don't understand why it's at 0 V. 18.5 V is right on the other side of PR235. PR235 and PR236 are fine.
I've tried replacing the ISL6251A (PU6) thinking there was an internal short of some kind, but that didn't change a thing.
1 (VDD) = 5 V
2 (ACSET) = 0 V with fluctuations as high as 0.4 V
3 (EN) = 1.13 V
22 (DCIN) = 18.5 V
23 (ACPRN) = 5 V
I checked all the nearby resistors and caps for shorts. No bad components were found.
I can follow the adapter voltage all the way to PQ52. PQ52 is off because ACOK# is at 5 Volts. That drew my attention to the ISL6251A . ACSET (pin 2) is at 0 V, so that explains it. But I don't understand why it's at 0 V. 18.5 V is right on the other side of PR235. PR235 and PR236 are fine.
I've tried replacing the ISL6251A (PU6) thinking there was an internal short of some kind, but that didn't change a thing.
1 (VDD) = 5 V
2 (ACSET) = 0 V with fluctuations as high as 0.4 V
3 (EN) = 1.13 V
22 (DCIN) = 18.5 V
23 (ACPRN) = 5 V
I checked all the nearby resistors and caps for shorts. No bad components were found.
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