STM32G030F6P6 TSSOP20 crystal oscillator?

[MarkJordan]

As I understand, the TSSOP20 version needs an external oscillator instead of a 8MHz crystal connected directly to the MCU pins. Is that correct?

I'm asking because I have seen a board on AliExpress using this same processor with a 8MHz crystal.

[TDK · Accepted solution]

Correct, the TSSOP20 doesn't have an OSC_OUT which means it can't be hooked up to a crystal directly.

No clue what's going on with that board. Schematic doesn't seem available. Probably the crystal is not very useful on it.

[BarryWhit]

Very curious. a schematic (could be typical AE misinfo) is available but shows no crystal

https://nl.aliexpress.com/item/1005005574646465.html

There's also a Baidu (Chinese Cloud drive) download link at the top of that page for a zip file of assets for that board, but it seems to be china only.

On at least one unrelated project, someone thought it was a good idea to connect a 16Mhz crystal to OSC32, I wonder if that's a clever hack or a *** mistake: hack.https://github.com/brunohoplite/stm32g030f6p6_evaluation_board/blob/master/PCB/Schematic_stm32g0f0_eval.pdf

Update: really?!? the word *** is censored? that's so ***ing ***. What a bunch of ***.

[oxomoxo]

Definitely a mistake ... Don't ask me how I know ^^ 

[RomainR.]

Hi,

The TSSOP20 versions of the STM32G0 only support an external HSE bypass oscillator on PC14 (OSC_IN), but they can also use a LSE crystal on PC14–PC15 as the SYSCLK source.

I would be curious to understand the purpose of this 8 MHz crystal on this STM32G030F6 board. I could not find any schematic for this board. Very strange !

If I were to use this kind of hardware, for a lower price and with slightly better PCB manufacturing quality, I would rather use this instead, especially since the schematics are available online:
https://github.com/WeActStudio/WeActStudio.STM32G0xxC0xxCoreBoard/tree/master

Otherwise, here our official reference hardware, which is fully documented and supported by our ecosystem.

https://www.st.com/en/evaluation-tools/nucleo-g031k8.html

Best regards,

Romain,

[oxomoxo]

> The TSSOP20 versions of the STM32G0 only support an external HSE bypass oscillator on PC14 (OSC_IN)

As you might have understood I made the same mistake as presented in the above board...

Could you elaborate on external HSE bypass oscillator concept ?

[RomainR.]

Hello @oxomoxo 
Refer to RM0454 in section 5.2.1 HSE clock and HSE bypass section.
In this mode the clock is injected on single OSC_IN IO (here PC14 for SON8, TSSOP20 and LQFP32 packages), the clock can be a sinus wave or digital square.
The HSE crystal can be only used on LQFP48 with the external 48MHz crystal connected on PF0-OSC_IN and PF1-OSC_OUT. (see also DS12991 Table 12)
Best regards,

Romain,