STM32L4 LSE 1Hz PPS

[patrislav]

Hi,

is it possible to use the L4's LSE in bypass mode, driven by a 1Hz signal?

I have a set of L4 chips on a bus and would like to feed them a 1Hz / PPS signal from a precise / temperature-compensated clock (and then use the LSE with /1 prescaler for the STM's internal RTC), so their system time is synchronized.

Any reason why this should not work?

At least there seems no minimum frequency for fLSE_ext according to L4 datasheet.

[Tesla DeLorean]

>>Any reason why this should not work?

The manual doesn't flag an reasons it shouldn't, PREDIV_S = PREDIV_A = 0 seems valid value, and it talks about division from 1 to 2^22

Suggest you try it. Tend to experiment here when we are "unsure" of how a circuit is implemented or behaves at the corners.

[patrislav]

Yeah, I got a bunch of nucleos lying around anyway, so I guess I'll just give it a try.