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10 years, 5 months ago.
External power supply problems Vbat and 9v power battery
i plugged a new 9v battery but all i see is the ld1 light flashing in red and ld3 has a sold red light the stm also seems to have overheated the chip and fried it, but i really need to know because i need to make something that is standalone and not hooked into the computer
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1 Answer
10 years, 5 months ago.
Very likely that the F401 is fried. The VBAT pin is only for backup of the real-time clock. VBAT should be between 1.65V and 3.6V according to the datasheet. In the nucleo the VBAT pin is also connected to VDD (3V3) through SB45. That means you have applied 9V to the 3V3 powersupply of the F401 ==> deadly force...
You should be able to supply external (battery) power through the Vin pin. Voltage range is between 5V and 9V.
well it seems vbat has completely fried my board programs only upload halfway
posted by Jedidiah oyeyemi 16 Apr 2014