STM32U5 controller RTC accuracy

[NM.1]

Hi,

I am trying to enable RTC functionality in Nucleo STM32U575ZI board. As one of my requirement I wanted to understand how much accuracy we can get for STM32U5 controller ?

Any documentation or suggestion would help a lot.

Thanks!!

[AScha.3]

RTC accuracy is , what your crystal is doing....see ds of crystal, then you know.

typical deviation maybe 20 ppm , but there is correction possible. read in rm , RTC:

> A digital calibration feature is available to compensate for any deviation in crystal oscillator accuracy. <

(in H7 rm)

[SSher.3]

If you're asking about LSI - its Ok for learning, but unacceptable for designs due to "huge" frequency drift​ for long term time application even with calibration.