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AD 9009 IQ phase test issues

Product Number: AD9009

Hello ,we used AD9009 none os vision for test IQ phase ,we have some issues !


Expect the phase  to be stationary or be locked 

environment :

 AD9009 TX connect to RX close loop ( the same board )

Temperature : keep a constant temperature

Local type  : internal  Local

TX seeting:

DDS frequency : 31.25KHz 

DDS sampling rate :480 MSPS

JESD sampling rate : 480 MSPS

RX resting :

JESD sampling rate : 240MSPS

We checked the IQ data each hours. (The first IQ data is used as reference value, and our phase calculation  is equal  to arctan(Q/I) )

Q1 : 


The IQ data go in the same direction with each hours ,  shown in Figure 1 ,and the relative phase increase with time shown in Figure 2.  How can we lock the phase??  


                                                   fig .1                                                                                                                                                                                                                                               fig .2



The I data with different amplitude but  Q data was be locked,  shown in Figure 3 ,and can observed the relative phase becomes move up and down ,shown in Figure4.  but the IQ gain becomes imbalance ,shown in Figure 5.  How can we lock the phase and make sure IQ balance??  


                                               fig .3                                                                                                                                                                                                                          fig .4


                                                          fig .5  

Could you show us which method  or setting can solve the problem ,thanks a lot.

Moved to correct forum and added product number tag.
[edited by: emassa at 5:15 PM (GMT -5) on 30 Nov 2022]