When powered on, the AD9249 goes into an initialization phase where an internal
state machine sets up the biases and the registers for proper operation. During
the initialization process the AD9249 needs a stable clock. If the ADC clock
source is not present or not stable during ADC power-up, it will disrupt the
state machine and cause the ADC to startup in an unknown state. In order to
correct this, an initialization sequence will need to be re-invoked after the
ADC clock is stable. This is done by issuing a DIGITAL RESET.