STM32L433 LPTIM External Clock Max Freqency?

[JWieb]

What is the max frequency when driving the LPTIM from an external clock?

I would like to drive the LPTIM1 from a STM32L433 to control a Boost switch regulator.

Since we can clock LPTIM1 from 80MHz PLL internal. Is this limit safe for external as well?

Ideally, we want 250kHz switching frequency while keeping STOP1 MCU.

[JWieb · Accepted solution]

I found 15MHz in this document.

https://www.st.com/resource/en/application_note/an4865-lowpower-timer-lptim-applicative-use-cases-on-stm32-mcus-and-mpus-stmicroelectronics.pdf

This should really be in the datasheets.

[waclawek.jan]

Thanks for hunting down this vital piece of info.

> This should really be in the datasheets.

+1

JW