nrf52832 Crystal frequency

[Eric]

The manual clearly states that the external HFXO should be 32MHz. However, if one would like to have precise 16kHz on the PDM and I2S interfaces a 32.768MHz crystal is required.

So, will things start to fail/degrade if I use a 32.768MHz crystal instead ?

[Eric]

Hi all !

Thank you for your input. Some clarifications:

1. I do mean the 32MHz, not the 32.768kHz.
2. To the PDM input I want to connect a device which only accepts a 1.024MHz clock. If I feed it with 1.032MHz (i.e. 32MHz/(31*64bits) = 16129..Hz) i experience audio artifacts.
3. I use a proprietay radio protocol, i.e. I'm not bound by any BLE(or similar) timing requirements.

But, If I understand you correctly, the radio as such requires an exact 32MHz to function properly regardless of the transmission protocol used. Correct ?

\Eric

[RK]

yes - as in the spec, 32MHz +/- 60ppm for using the radio (non BLE). The radio uses the crystal to generate the correct frequencies.