STM32F427 does not boot after power on

[Bogdan]

Posted on April 26, 2018 at 17:16

Hello,

i  am using a design with a STM32F427  100pin package, and notice after leaving the board unpowered for several hours if i power up again, the software its not starting.

If i retry the restat the power it will stil not work, only after 3-4 retries. 

If i have the change to get starting  the software, then if i power off/on   it still works.

Boot1 - pin is left floating 

Boot0 pin - is tied to ground trough a 4K7 resistor

Reset pin - is tied to 3.3V trough 4k7 resistor.

Capacitors from pins 49,73  ( V_CAP) are 100nf X7R smd type

What is causing this strange behaviour?

[waclawek.jan]

Posted on April 28, 2018 at 09:30

Analog supply/ground pins not connected?

The power supply pins are all connected,  the ground pins the same.

How exactly did you check this? Can't there be a bad solder joint?

Software issue?

I am wondering if this is a software issue, since once the software starts everything seems to work perfectly.

Try with a trivial blinky software to exclude software problem.

JW