https://devzone.nordicsemi.com/f/nordic-q-a/10403/32khz-synth-clockHi there, I&#39;m having some truble to understand how to set a synthetice 32khz clock from the 16Mhz external crystal. Right now I have the next code working fine: NRF_CLOCK-&gt;LFCLKSRC = (CLOCK_LFCLKSRC_SRC_Synth &lt;&lt; CLOCK_LFCLKSRC_SRC_Pos); NRF_CLOCKen-USTelligent Community 13Tue, 24 Nov 2015 11:27:47 GMThttps://devzone.nordicsemi.com/thread/38623?ContentTypeID=1Tue, 24 Nov 2015 11:27:47 GMT137ad170-7792-4731-bb38-c0d22fbe4515:583f45c2-ccd9-40fd-a8d4-2b930350a06eovrebekk<p>Hi Daniel</p> <p>The last alternative is the correct one.</p> <p>Synthesizing the 32k clock from the 16MHz clock only makes sense if the external 16MHz crystal is running, so you should start that first and then enable the 32k clock.</p> <p>Please keep in mind that the current consumption is quite high in this mode, and it is not a very good option if you are looking for long battery life.</p> <p>Best regards<br /> Torbjørn</p><div style="clear:both;"></div>