STM32G071GB (UFQFPN28 - 28 pin package) HSE pins avaliable?

[Dstra.1]

i am planning to use HSE on STM32G071GB (UFQFPN28 - 28 pin package)

datasheet STM32G071 on page 41 does really make it clear if HSE pins are available in small package (28pin)

datasheet states:

PC14: OSC32_IN, OSC_IN

PC15: OSC32_OUT

is OSC_OUT missing in datasheet. is there a typo?

[Tesla DeLorean · Accepted solution]

A lot of the low pin count devices basically have a CK_IN (HSE BYPASS) where you supply an external​ clock, perhaps a TCXO you already have for a radio, Ethernet or something.

[Dstra.1]

Thank you for your answer.

So, on those low pin count devices, i can't use external high-speed crystal?

(but i could still supply external clock to OSC_IN pin?)

[Andreas Bolsch]

Yes, you could supply an external clock to OSC_IN. Another option would be to use LSE with 32.768 kHz crystal and trim HSI regularly as described in section 5.2.15 in RM. Whether this rather coarse trimming is sufficient depends on your requirements ...

By cascading serveral timers you could even get long term accurancy similar to LSE if you accept some jitter.

[Bouraoui Chemli]

Hello @Dstra.1​ 

OSC_OUT is not missing in datasheet. Indeed on 32 pins and below, no OSCOUT on G0 devices.

It’s mainly coming from the fact that all embedded peripherals of this device can function properly on the HSI, so no strict constraint on HSE, if for some particular case you need one, no choice then to use an external oscillator system or a TCXO and using OSCIN pin in bypass mode.

Best regards,

Bouraoui

[Dstra.1]

@Andreas Bolsch​  thank you for your answer.