My customer are using FR5849 in a power consumption critical application. They want to change DCO frequency to 1MHz in most of time, but change to 8Mhz when high speed calculation needed. They found when they change from 1M->8Mhz, it will need 900us to stable. And when change from 8MHz to 1MHz, it will need 120us.
They want to know is it normal? and why need 900us to do such DCO frequency change?