I have purchased the ADC12D1800RB and I have been trying to intentionally introduce bandwidth mismatch spurs (dynamic gain and amplitude) in DES mode for research purposes. So far, I tried several setups, and none of them presented relevant spurs which could not be fixed with the standard gain and time skew calibration.
As I understood, the "ADC12D1800RF" datasheet says that the DESIQ mode shorts I an Q, which I presume that it is also shorted for the ADC12D1800. I would like to introduce the same errors as the "ADC12D1800RF" DESCLKIQ mode, described in the related post e2e.ti.com/.../1038514 "The DESCLKIQ mode does not have this internal connection of the signal to both converters. In this mode, the signals are completely independent, similar to the non-DES mode. Due to this difference, and the reduced loading on the signal, the bandwidth does improve. The trade-off is that the matching between I and Q signals is no longer as good. Our testing to date has found that it is nearly impossible to connect the signals externally in such a way that they will be adequately matched over input frequency. The result is that significant interleave spurs are present in the spectrum due to the amplitude and timing mismatch between the 2 input signals."
