Is an external ADC clock synchronized to the CPU clock?

[tjdyhdsfeadgstdj]

I know in some peripherals, like in a lot of times, the external clock is resynchronized to the CPU clock.

In an ADC, that could add jitter. Does anyone know if using an external sample clock on a SAR ADC will be resynchronized to the CPU clock or will it asynchronously start a conversion?

[waclawek.jan]

Choose such ADC which allows using external clock.

JW

[tjdyhdsfeadgstdj]

Hi. My question is specifically about the external clock. Does it clock the ADC sampling asynchronously, or is it resynchronized to the CPU clock.

[waclawek.jan]

What exactly do you mean by *external clock* here? Post a block diagram perhaps.

JW

[BarryWhit]

- You don't normally synchronize clock signals, you synchronize external signals when they cross clock domains (such as when they enter the STM32).

- If you have an external ADC, it depends - on how acquisitions are triggered, how acquisitions transfer to the STM32 is triggered, and though which comm peripheral the acquisitions are communicated back to the STM32. It also probably depends on the specific ADC you're using. i.e. "Error: Insufficient data".