DSO150 : MCU fried ? No problem


All of a sudden the board consumption jumped from 100 mA to 500 mA
The regulator & MCU were getting REALLY hot

After a bit of investigating, it appears that PD0 was shorted to ground INSIDE the MCU.
It is most likely that  i've connected the analog board in the wrong pins and shorted it out.

Ooops....


Now i'm really happy i've spent time watching Louis Rossmann  entertaining videos :)
No problem, let's take a bluepill board (2$ on ebay)  and swap the MCUs, they are both STM32F103

Hotair to remove the old & new ones , soldering iron, dragging solder THEN lot of flux to remove the shorts,  => No problem , back in business.

The donor board


The end result, with flux everywhere between the pins :)


Thanks Louis !

The only issue i had to fix afterward was the MCU was running really really slow
I had to resolder the C1 / C2 caps that are driving the quartz.
Now everything is back to working state on my Frankenstein DSO 150, circa 2017.

Edit :
It tends to be reluctant to boot sometimes, probably damaged a bit something in the process, just need to try a few times and it's ok.

Edit 2: 

I've cleaned up all the flux/solder that was stuck between the MCU pins and now it seems fine.
Probably a very tiny short cirtcuit/cap effect that was preventing the quartz from oscillating.



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