Can nRF52840 SPIM speed be 8MHz with 1.8V power supply?

RE: Can nRF52840 SPIM speed be 8MHz with 1.8V power supply?

run_ar — Tue, 02 Feb 2021 09:37:38 GMT

Looks like you already checked. And Yes, these pins are ok to use for High speed protocols.

RE: Can nRF52840 SPIM speed be 8MHz with 1.8V power supply?

pjm — Sun, 31 Jan 2021 14:00:02 GMT

Hi,

Thanks for your reply.

The pin assignment of SPI is as follow:

The GPIO P0.14\P0.22\P0.24 usement as follow pictures:

please help check whether the pin assignments is OK or not.

RE: Can nRF52840 SPIM speed be 8MHz with 1.8V power supply?

run_ar — Tue, 26 Jan 2021 12:26:02 GMT

Hi,

Yes, SPIM should be usable at 1.8V but it's likely you will need to enable High drive strength. And also make sure you have reasonable short lines. If they are to long your rise/fall times will increase. You can see the rise/fall times in the GPIO spec here: GPIO Electrical Specification. Please also make sure you do not use any of the "Standard drive, low frequency I/O only" pins as described here: Pin assignments