STM32L4: Which can be the LSE Drive Level to use with an external oscillator with CL of 12.5pF

[gon1332]

External oscillator: MC-146 32.7780KA-A0

Load capacitors used: CL_1 = CL_2 = 8pF

With Drive Level of Low the application works. I would like to obtain better understanding of how the G_m_crit_max is connected to the CL.

I've had a look at AN2867 - Oscillator design for STM32 MCUs.

According to section 4.1, a better Drive Level would be the Medium?

Moreover the STM32L496xx Datasheet has this table:

[js23]

A 12.5pf crystal with 8pF load caps is severly underloaded, you will need approx 18pF load caps (depending on PCB) Most likely the highest drive level will be needed.

I would not recommend to use a 12.5pF crystal, go with 8pF or 9pF instead (and 10-12pF load caps)

[gon1332]

Thanks for your guidelines.