Switch doesn't turn on

Guest 11935 — Sun, 26 Mar 2023 20:12:00 +0000

Hi
First post. Thanks to share your work and tips on youtube. Interesting.

Well, I'm facing to a switch that doesn't turn on and I did some checks but now i'm in a end line.

When using a usb tester : 15v / 0.5a
Vbus = 15v (after mosfet)
BQ is working (batterie is loading)
VSYS (4.2v) is present everywhere

I extracted MB and injected 4.2v on VSYS. No shorts.
I tried to turn on by shorting pin 1&2 with tweezers on power button connector.

I have ~135-140ma instead of ~170-180mA (I compared with others working well devices I have)
And stuck here.

I checked all the voltage outputs of MAX77620 for first stage boot . All is ok.
But on south MAX77621 no output voltage (I should have 0.95v right ?).

I replaced it. But same behaviour...

Have any idea ?!

Thanks,
Charly

power-point-switch.PNG

Switch doesn't turn on - Repair Questions

Switch doesn't turn on