Stm32f407 stopped and over heat When disconnect wires running Spi communication

[MDavo]

Hi,

I'm using two STM32F407 LQFP-144 in SPI communication , one Master and one slave

when power supply is connected and program is running and spi send & recieve is okay , we disconnect board ( wiring) and then connect again , face off over heating ic and stm32f407 completely unusable

I read about hot swaping in the web but i'm not very exprience in this topic

[Uwe Bonnes]

STM32 overheat is often a sign that maximum input voltage on some pin was exceeded and the IC damaged. Read the datasheet about maximum rating carefully and look at possible errorr cases with your board.