Probably nobody will see this issue any more, but just in case, I'm posting it.
Laptop shuts-down randomly due to 6251ACIN signal disappear when capacitor PC169 gets a certain level of temperature.
PC169 is connected to pin 5 of PU4 (P2805MF (+VH28 generator))
I have no data-sheet for P2805MF, and wonder why is affected 6251ACIN signal, (pin 6 of P2805MF) and not the +VH28 voltage. (pin 8 of P2805MF)
6251ACIN signal is obtained from +VAD_1 by two resistor, for setting the ACSET voltage needed for ISL6251A in order to detect the 19v. applied to dc-in jack connector.
Capacitor PC169 has been replaced, and laptop is working properly now.
I hope this information will help someone else.
Вложение:
capacitor PC169.jpg
