820-00928 Charging/Power issues

[BCConnection]

Im not overly familiar with how this entire USB system works

Liquid damaged board corrosion and burn pad on UB300 and corrosion under UB400. Reballed UB400 and swapped UB300 for good chip.
Get 5v at fuse but wont go to 20v.

Ive poked around and found a few 3.3v lines but not sure of what all is needed here to take 5v up to 20v.
If the chip I replaced isnt programmed would it keep the entire system from working?

 

[2informaticos]

CD3215 chips have firmware.
Be sure the replacment has the same termination code; i.e. C00, A01, B03.
Always better to have donor board, same model.
But this will not assure the chip from donor board is "alive".
All 4 ports must work, in order to get 20V.

 

[JohnB8812]

Yep have to have PP3v3_G3H and all four CD3215s must work and be the same firmware code. Best to usually replace any of which are corroded when dealing with 5 volts on DC in rather than reball.

 

[BCConnection]

Are "new" chips not programmed? Finding parts boards for these with the ends not cut off is very difficult. I have B03 and this board is C00

 

[BCConnection]

Nevermind Louis has them on the site lol

 

[2informaticos]

Solder C00 and comment the result...

 

[JohnB8812]

Yeah new chips have programming already and will work if from reputable source. I got mine from Louis had no issues. Must use C00 tho B03 won't work on your board if it came stock with B03