Using an external 32 KHz crystal with RP2350

[JeremyGrosser]

The datasheet doesn't really specify how LPCK should be connected. Is it a CMOS clock or can it drive a crystal? If it's a crystal, what load capacitance is expected? What power consumption can I expect compared to using the internal LPOSC?

Maybe this should be a section in the Hardware Design document?

[mike-stimson]

The LPCK is hooked up to a GPIO, and these are all purely digital inputs (ignoring the ADC capable ones), so it's a CMOS clock. The only inputs capable of driving a crystal are XIN/XOUT.