Hello,
We are using the MCU S9KEAZN64AMLC in our design with an external crystal (ECS-160-12-37BQ-CTN-TR, load capacitance 12 pF).
We observed that the crystal drive level is about three times the recommended 100 µW.
Currently, we are using HGO = 1 (high gain) in our code because the ESR of the external crystal is 150 Ω.
Could you please advise which setup is correct, high gain (HGO = 1) or switch to low gain (HGO = 0) for this crystal?
If HGO=1 is correct why drive level of crystal too high?
Hi @amitsinhaEM,
According to the datasheet, and given the crystal's ESR of 150 Ω, your setup should be configured with High Range and High Gain Mode.
Set the oscillator control register as follows:
OSC_CR[RANGE] = 1 (High frequency range)
OSC_CR[HGO] = 1 (High gain mode)
Please ensure that both the RANGE and HGO bits in the OSC_CR register are properly set.
Best Regards,
Pablo
