I am using the high speed ADC of AD9230 for DPD feedback channel.
The sample rate was 120MSPS， analog input common mode voltage was 1.46V; and Rbias pin was 0.5V; SDR mode, two complement output.
In order to verify the ADC's noise floor, I tied VIN+ and VIN- together ,and I found the output bit5 to bit 11 was not correct. It seems VIN+ - VIN- >0.
When I use the test mode , the digital output was correct, so the digital transmission was ok.