I bought a AD9643 evaluation board and its data capture board for my experiment related to RF.
I read a datasheet of AD9643 dozens of times, but I do not know about the input frequency range of AD9643.
In my experiment with AD9643 with evlauation board and its data capture board, there were some distortions when frequency of input signals is very low( e.g. input signal is rect(squre) function and its frequency range is in 0~5MHz).
In other words, I just trying to obtain a raw data according as a input analog signal using AD9643 evaluation board and capture board.
But, in my experiment, output data is not correspond to input signal. It operates same as a high-pass filter.
Also, by the datasheet(e.g. AD6643/AD6649/AD9613/AD9643 Schematics), there are some RF Transmission Line Transformer(e.g. ETC 1-1-13).
However, the ETC 1-1-13(RF transmission line transformer) is operated in range of 4.5MHz~3000MHz by its datasheet.
Thus, I'm very confused what is the input frequency range of AD9643. I think there is no document which tells accurate frequency range.
Please tell me a guaranteed input frequency range of AD9643 or related documents ( especially, lower limit of input frequency)