STM32F756ZGT6 - short circuit issue

[dharanik_1399]

I am facing a short circuit issue on my custom board, which uses the STM32F756ZGT6 microcontroller. The enabled peripherals on the board include USB, SD CARD, ETHERNET, UART, SPI, and I2C.

This is the second time I have encountered this issue on my custom boards. The short circuit is limited to the microcontroller itself, while all other peripherals on the board continue to function without any issues.

I kindly request your assistance in identifying the possible causes and providing guidance to resolve this problem.

Thank you for your support.

[Tesla DeLorean]

So likely cross connecting supply and LDO output.

Show all the supply connections you have made. Show VCAP usage, and check capacitance and voltage there.

If this is a second broken design I'd suggest reading through the Data Sheet more carefully to better understand the expectations. 

[STOne-32]

Dear @dharanik_1399 ,

Try to share your schematics and at which moment the issue is happening ? After which operations or configuration.  Most of HW issues could Be :

• I/O race conditions if forced externally to ground or VDD .   ESD issues 
• VCAP exceeding datasheet values  etc 

let us know .

STOne-32

[dharanik_1399]

Actually the Micro-controller is not get short-circuited as soon as it got placed onto the board. After working fine over a month it got short-circuited suddenly. Here I attached the power supply circuitry of the schematic,

 

[dharanik_1399]

Hi, actually we cannot able to capture the moment of short-circuit. Because it happens randomly. My board was working fine over a month then only it got short circuited. I attached the schematic here, PFA.