Jitter when switching from and to 16MHz oscillator to timer

[victor]

Hi, I generate a pwm signal using timers and PPI on NRF51 and use BLE and rbc mesh in the background. I have notised about 10us jumps in duty when the BLE or RBC stack enabled/disabled oscillator. Is this a known problem and if so is my fix correct? I call sd_clock_hfclk_request at boot to make sure the crystal is always on and now I dont see the jitter.

[MartinBL]

Hi,

What do you mean by "jumps 10us" The internal RC oscillator is not very accurate (+-5%). So when the radio ramps up and starts the external crystal, which has a much better accuracy, you can expect to see some shifting in frequency.