https://devzone.nordicsemi.com/f/nordic-q-a/12270/side-effect-of-adding-a-lfclk-of-32-768khz-with-esr-90k-ohm-oscillatorHi, Side effect of adding a LFCLK of 32.768khz with 90k ohm ESR oscillator? where as data sheet recommends Max value of 80kohm. Side effect of adding lower drive level crystal oscillator 0.5uW where as nordic recommends 1uW Maxen-USTelligent Community 13Wed, 02 Mar 2016 13:33:06 GMThttps://devzone.nordicsemi.com/thread/46391?ContentTypeID=1Wed, 02 Mar 2016 13:33:06 GMT137ad170-7792-4731-bb38-c0d22fbe4515:bc0e9814-d38f-41af-b527-72dbf8f20addFormerMember<p>A larger ESR increases the start-up time for the crystal. I would not recommend you to use a crystal with a larger ESR then the max value stated in the product specification.</p> <p>Maximum drive level for a crystal oscillator is already being discussed in <a href="https://devzone.nordicsemi.com/question/69890/urgent-lfclk-in-nrf51822-power-rating/">this</a> thread.</p><div style="clear:both;"></div>