Did I break my 407 with +5V?

[LMI2]

Posted on June 26, 2018 at 01:12

I accidentally used a 5V regulator instead of 3.3V. After fixing that the SWD dongle/ST link says no connection to target. This happens to be my only prototype now. Building a new or swapping the 100pin STM32F407 isn't fun. Has anyone experience of this kind of situation. The absolute maximum VDD is 4.0V.

I have checked SWD connections and Boot0 is pulled low.

[T J]

Posted on June 26, 2018 at 01:48

sorry to say, but Yes I think you are correct.

put 3v on it, does it get hot ? definately faulty.

To remove the chip

you have to get the underside on the board hot

my rework station has the bottom heater and what looks like a paint stripper on top.

https://www.aliexpress.com/item/Yihua-853AAA-650W-SMD-Hot-Air-Gun-60W-Soldering-Irons-500W-Preheating-Station-3-Functions-in/32663262041.html?spm=2114.search0104.3.1.58274dcaGc8WX9&ws_ab_test=searchweb0_0,searchweb201602_3_10152_10065_10151_10344_10068_10130_5722815_10342_10547_10343_10340_5722915_10548_10341_5722615_10696_10084_10083_10618_10307_10131_5722715_10132_10133_10059_306_100031_10103_10624_10623_10622_5722515_10621_10620,searchweb201603_43,ppcSwitch_3&algo_expid=ec3a289e-2f6e-447c-9a25-a82c60c5341a-0&algo_pvid=ec3a289e-2f6e-447c-9a25-a82c60c5341a&transAbTest=ae803_1&priceBeautifyAB=0