a1286 820-2330 no power

[lordgeny]

A little questionne , i found PP3V3_G3_RTC lower than 3.3 its 2.7v ,

since i readed that is requireed for PM_SLP_S4_L

just for information the other misuration :
C7771 Pin 1=1.08v
PPBus_G3H 12.6
PP3V42_G3H 3.4v
3V3_S5 present

[mon2]

Re: a1286 820-2330 no power

See attached.

Check the voltage IN to the load switch for the PP3V3_G3_RTC rail.

Then remove all power and check the resistance to ground of PP3V3_G3_RTC .

Post all readings.

[lordgeny]

Re: a1286 820-2330 no power

Voltage in 3.4

resistance 12mega
diode mode on pin 5 0.516

[lordgeny]

Re: a1286 820-2330 no power

this is the datasheet seems to be the correct voltage at vout 2.8v

[mon2]

Re: a1286 820-2330 no power

Good job on the clarification. The part number of the ldo is in the data sheet but the text is showing as 3v3 output so assumed incorrectly that this was a load switch =like a relay.

See here and follow the check list:

https://www.it-tech.com.au/mac-q-a/pm-slp-s4-l-timing/