Hello team,
My customer is wondering how can they adjust the frequency of crystal?
Customer usually use external capacitors to adjust the frequency.
Is it via CAL_CFG1 register?
If frequency is adjusted by CAL_CFG1 register, can they use same setting for mass production? There are some part to part variation on crystals.
Best Regards,
Kei Kuwahara
Hi Kuwahara-san,
As long the chosen crystal has the same load capacitance as specified in the datasheet, the external loading capacitors are not needed.
Correct, the CAL_CFG1 register is used to adjust the crystal oscillator's frequency. Adjustment should be done on each RTC in production for optimum accuracy. If this is not possible, (in fact, the calibration takes time), use tight controlled crystal.
