hi sir
there is no Confusing
laptop is not charging the battery that is the problem
What confused me was that 2.8V from DC jack...
I thought it's shorted, either the board,jack or something in charger circuit...
Also thought that you tested laptop with battery & charger connected at the same time...
Anyway...
Could you check resistance @ PL4001 & post all voltages of PU4001?
what should be the current on pq4001 pin 4 and 5 no current
I'm not 100% sure, but in this design the pq4001 is a kind of charging switch...
It will push voltage to PU4002 gate if there's something wrong(or if it's not getting PWR_CHG_ACOK)...
PU4002 is P channel, so it will switch off when gate voltage is similar to S & G voltage...Maybe I'm talking shit, but it does make sense, therefore these 2 should be OK...
Why are the voltages different now???
It's BQ24707A...
Leave it on charger for 2 minutes & I think you'll get the same voltages as in your 1st post...
I think it's in Over Current Protection and therefore charging is disabled...
The IC cannot maintain the input current level if the charge current has been already reduced to zero. After the
system current continues increasing to the 1.66X of input current DAC set point (with 2.5ms blank out time),
IFAULT is pulled to low and the charge is disabled for 1.3s and will soft start again for charge if ACOC condition
goes away. If such failure is detected seven times in 90 seconds, charge will be latched off and an adapter
removal and system shut down (make ACDET < 0.6V to reset IC) is required to start charge again. After 90
seconds, the failure counter will be reset to zero to prevent latch off.
Think the IC is dead / shorted...Or some cap around shorted...
It's a hardcore case without schematics...
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