STM32G474 MCU port protection

[Manu Abraham]

Hi Folks,

Greetings!

At my end have a STM32G474 HRTIM output driving a MOSFET gate driver such as IR2110.

In some weird cases encountered, when the MOSFET blows up, it takes away with it the

gate driver as well.

Not in all cases, but in some situations, I have noticed that the G474 HRTIM output port also does get damaged.

I must mention beforehand, that it is not at all the fault of the MCU, but instead, I am trying to better protect the MCU port pins under such a circumstance.

What would be the "right way" to do it ? (Put a buffer in between the MCU and the gate driver as a sacrificial device ?) Any other better ways to go about it ?

Thanks,

Manu

[Uwe Bonnes]

Yes, a buffer will and a layer of protection and could probably drive the Mosfets with 5 volt against 3.3 Volt when only driven from the CPU.

[Ozone]

When your power MOSFET drives inductive loads, I would opt for a galvanic isolation.

> What would be the "right way" to do it ? (Put a buffer in between the MCU and the gate driver as a sacrificial device ?) 

That sacrificial devise must absorb the worst-case power surge possible, and fast enough.