820-3115 PP3V42_G3H too high

XooP

New member
I have been working on this board for å while now, but I can´t figure out why PP3V42_G3H is so high.
Sometimes I get green light, but when that happens the PP3V42_G3H is about 3.45V, usually i get 3.46-3.47.

I have replaced both U6990 and U6901 (don´t know why i did this though).

As far as I can see the resistors and capacitors around 6990 are fine.

[FONT=Verdana, Arial, Tahoma, Calibri, Geneva, sans-serif]What am I missing here?[/FONT]

[FONT=Verdana, Arial, Tahoma, Calibri, Geneva, sans-serif]By the way, It's not my multi meter which is off, other boards measure 3,41-3,42 with the same multimeter.[/FONT]
 

larossmann

Administrator
Staff member
Are you using 85w charger or 60, original or knockoff, and what was the original problem with this board(if any)? Liquid, drop, out of the blue?
 

aprendiz

Moderator
No Title

Schematic says Vout = 3.465V.... I guess there is no problem there.... Did you check one wire circuit???
 

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XooP

New member
Hmm, yes, I have checked the one wire circuit. Strange how every other board I've worked on measures +-3,41.
 

larossmann

Administrator
Staff member
Well there you go. Remove the edge bonding around the SMC, flux and reflow. aprendiz beat me to it.
 

dukefawks

Administrator
Don't fully reflow the SMC, just give it 150C-180C it should be enough to clear the crap under it. Reflowing it is too risky as there may still be some of the corner glue under the SMC screwing things up.
 
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