NRF51 External Clock Issue on Custom PCB

RE: NRF51 External Clock Issue on Custom PCB

kaushik_ray_2 — Tue, 17 Jul 2018 15:22:39 GMT

Just for future reference if anyone else is looking for the same problem. After i installed the 32.768 Crystal NRF_CLOCK_LF_SRC_XTAL works great.

RE: NRF51 External Clock Issue on Custom PCB

kaushik_ray_2 — Mon, 16 Jul 2018 20:10:52 GMT

Thanks Turbo I will connect a 32.768kHz but in the meantime I have tried NRF_CLOCK_LF_SRC_SYNTH and it is working

Thank you.

RE: NRF51 External Clock Issue on Custom PCB

Turbo J — Mon, 16 Jul 2018 19:44:50 GMT

The 16MHz crystal is not enough. For lowest power "operation" (or rather sleeping), you would also need a 32.768kHz quarz - which is not available on the Adafruit module. You could try using NRF_CLOCK_LF_SRC_SYNTH, but this will keep the main crystal running AFAIK.