STM32G474RET6 BOR level

[flying_car]

Hello everyone,

I am quite new to this and I am using the STM32G474RET6 with BOR level 4. I changed the BOR level to level 0 and the board did not work properly. After changing it back to level 4, everything worked fine again.

Is there any relationship between CPU speed (it is 168Mhz in our case) and BOR level?  We are not sure how to properly select the BOR level. 

Thank you.

[waclawek.jan]

> Is there any relationship between CPU speed (it is 168Mhz in our case) and BOR level?

Not directly.

However, higher BOR level holds the mcu in reset until VDD reaches a higher level. Does your setup portion of program - in particular, setting of FLASH waitstates, account for lower VDD?

Also, depending on the power supply design and PCB layout, the power supply may be prone to dip when suddenly loaded by mcu running high system clock frequency, while it's still in its startup.

JW