"If the EN_AGC pin is (not) used" is a clause occurs a few times in UG-570 and UG-671. What does this mean?
Specifically, in UG-570, Table 26, in order to prevent gain unlock conditions, depending on whether the EN_AGC pin is used, we need to set bits differently. Also on the same page in UG-571 (pg. 46), it says "If the EN_AGC pin is not used, then the Gain Lock Delay bit must be set high".
There is very little mentioning about "Gain Lock Delay" in both UG-570 and UG-671. And it is not a single bit, but an 8-bit value in Reg 0x021.
1. Looks like there is a way we can set AD9631 to neglect EN_AGC pin, i.e., not used. Am I right? If so, how to set it up?
2. Can someone give a detailed explanation on how to use the 8-bit Gain Lock Delay in Reg 0x21?