I am working on AD9364 and I see a very strange transient at the beginning of a transmission.
The device is initialized and configured using the non-OS driver.
Transmitted signal is a clean CW (constant value on digital data port).
The state machine is controlled via ENABLE and TXRXN discreets.
After a rising edge of the ENABLE signal, in Tx mode, there is an odd transient, as shown in the following zero span measurement:
Unsurprisingly, this transient causes a lot of spurs all over the nearby spectrum (few Megs).
Is that considered normal?
Is there any way to avoid or suppress this transient?