LFSYNT - Low Frequency Clock Synthesized from HFCLK

[eiadj]

Hi,

Having gone through the nRF52832 datasheet, the only discernible drawbacks of moving from an external crystal to synthesizing the Low frequency clock from the high-frequency clock appears to be:

• increase in run current from 0.25uA to 100uA
• an additional 8ppm of tolerance on the clock

Based on the requirements of the clocks for system performance that additional 8ppm doesn't appear to be problematic unless the ANT stack is used (it isn't).

Am I missing any drawbacks here?

[bjorn-spockeli]

When synthesizing the LFCLK from the HFCLK you also need to add current consumption of the HFCLK which needs to run all the time, i.e. 250uA. So the total will be 100uA + 250uA = 350 uA.