https://devzone.nordicsemi.com/f/nordic-q-a/7571/hf-clk-source-in-case-of-lf-crystalHi, I was wondering if it is regual that configuring softdevice for a low frequency oscillator 32.768 kHz using the function: SOFTDEVICE_HANDLER_INIT(NRF_CLOCK_LFCLKSRC_XTAL_20_PPM, false); the high frequency source in the CLOCK register HFCLKSTATen-USTelligent Community 13Thu, 11 Jun 2015 18:19:32 GMThttps://devzone.nordicsemi.com/thread/26968?ContentTypeID=1Thu, 11 Jun 2015 18:19:32 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c7121888-2b3d-472d-835b-bcca2347d26cSusheel Nuguru<p>All the examples using softdevice use the LFCLK configuration you mentioned. More info can be found here. <a href="https://devzone.nordicsemi.com/question/953/what-low-frequency-clock-sources-can-i-use/">devzone.nordicsemi.com/.../</a></p> <p>Softdevice uses few peripherals that need the HFCLK which uses internal RC oscillator. So RC is started and stopped automatically depending on your peripheral activity, and your application does not have to do anything for it. Make sure that your disable the peripherals when idling and RC Clock source regulator will switch on/off accordingly.</p><div style="clear:both;"></div>