Attached the old datasheet that we had from the very beginning. Please see page 11 with the pin descriptions, the table indicates that pin A5 is used for Tx_mon input.
Now, the latest datasheet (http://www.analog.com/media/en/technical-documentation/data-sheets/AD9364.pdf) shows that pin A5 should be GND and M5 should be Tx_Mon.
In our design we use A5 pin as the Tx_Mon input (pin M5 is tied to GND). Somehow this feature works, if we read TX_RSSI 2. This suggests that AD9364 includes both Tx_Mon 1 and Tx_Mon 2 – but we are not sure that Tx_Mon 2 works correctly. In general, Tx_Mon feature uses a portion of the receiver to measure the transmitter power – so if the IC has only one Rx path, the Tx_Mon 2 functionality may be limited, or not work correctly at all.
Any clarification on this issue will be appreciated.
Thanks and best regards,