Thank you and I understand your concern about wasting my time on this board that may never be repaired. Because I found two burnt diodes that are responsible for the power supply in the USB section, I believe that these diodes are burnt to prevent damage to the important parts of the board, and therefore I was very eager to repair the board(I think that the processor and other important parts are still healthy).The PMIC is the square chip near the corner of the board where the USB-C socket is.Hi.
I have raspberry pi4b 4G model and i useing it about 2 weeks, suddenly it has act led on all the time.
When i was diagnosed it, i saw it has 5v on 5v pin and again has 5v on 3.3v pin!!!
I look for board views but can't find 5v to 3.3v converter curcuit in pi 4b.
The reduced schematic for the 4B does show that the PMIC produces multiple power rails.
As already hinted the board is very likely beyond ecomomic repair.
Apart from this issue, I live in a country where the price of this board is sold at about twice its global value, even though it has a low income level, And this issue makes it very difficult for me to buy this board again, and since I need this board for a university project, I have to repair it.
How can I be sure that PMIC is completely burnt?
Statistics: Posted by Mani007 — Mon Sep 16, 2024 8:50 pm