nRF52832 hangs when low-power mode is used

RE: nRF52832 hangs when low-power mode is used

ketiljo — Tue, 27 Nov 2018 07:58:56 GMT

The reference crystal has a lower CL value.

Please test this.

RE: nRF52832 hangs when low-power mode is used

bluera1n — Mon, 26 Nov 2018 14:29:03 GMT

But reference design also uses 12pF.

Is 3pF difference huge for 32.768kHz XTAL?

RE: nRF52832 hangs when low-power mode is used

ketiljo — Mon, 26 Nov 2018 14:22:42 GMT

For a 9 pF crystal, you should use 15 pF load caps.

Ccap = CL * 2 - 4 pF

RE: nRF52832 hangs when low-power mode is used

bluera1n — Mon, 26 Nov 2018 14:19:41 GMT

XTAL's CL is 9pF. I'm using exactly same XTAL used in reference design (CM8V-T1A).

And load cap is 12pF in parallel.

BTW, I found new symptom which shows weird behavior in buck output voltage when MCU hangs.

But I'm not sure there is correlation between 32.768kHz and buck converter.

RE: nRF52832 hangs when low-power mode is used

ketiljo — Mon, 26 Nov 2018 13:51:04 GMT

Looks like maybe there's an issue with the 32 kHz crystal. What is the CL value of the crystal (from the datasheet) and the value of the load caps you are using?