I am interested in using the AD9208 as a wideband digitizer to subsample RF signals, and I like that the input bandwidth for this device is 9 GHz. However, I wish to have control over the sampling frequency (Fs). In the datasheets for AD9208, the tables list only three possibilities for Fs: 2.5 or 3 or 3.1 GS/s. But are these the only allowed values? What should I do if i wanted it to be lower value, for example?
Similarly, I am interested in AD9213 because of its wide RF input bandwidth (6.5 GHz), but the datasheets mention max Fs as 10 GS/s, without clearly explaining whether lower Fs values can be used and how?
Any help or suggestion would be appreciated.
(note: I am not necessarily stuck with these product. Any wideband sampler would be welcome, as long as it has good performance and number of bits (say 12 bits or over), and input BW higher than 4-5 GHz.)