What CSD2X configuration ( IDAC, Rb , 1x, 2x ) has lower noise crosstalk from the power supply?
There should be no difference in power supply crosstalk between the 1x and 2x configurations. The Rb configurations probably have lower power supply crosstalk, since a fixed, very stable resistor is used instead of the IDACs, which probably have some power supply noise. However, the IDAC configurations are generally better, since it give much more flexibility.
