Hi
i am having no power issue here
after the first mosftet i have 0.15V (pulsing up to 0.8V or may be more, but too shortly)
and after secondary mosfet i have 3 to 4 Volts
I have already changed the entry mosfets PQ8801 ans PQ8802 (twice), and the regulator BQ735
i also removed PR8806 to be sure to have no short after AC_BAT_SYS in a sub circuit.
My customer claimed the battery died and after this he got this issue.
Did anyone encounter a same issue and fixed it ?
(i know i could just put a wire there, but battery would be useless, but i'd like to find he solution)
ty
Sometimes one of the two 19V from power supply entry mosfets gets in short circuit which cause the second one to stop working (gate closed) as these two work together by reaction on the gate mosfet signal pin. Or a short circuit after the second mosfet, example a short capacitor which is most common, will cause these two entry mosfets to close, so no voltage on the board. Can be also in short one of the mosfets that powers the processor and you can check this by removing the processor from the board if have socket. More I cannot say as I don't have your board in my hands to check it and can be so many other problems.
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