I am looking for a RF switch or equivalent function to switch between a high speed gigabit rate digital data (16.5Gbps) signal and a dc signal that may go below ground. I found HMC547LP3 / 547LP3E that could work given its high bandwidth and the fact that it is specified down to DC freq. I need clarification on the lowest operating frequency and the absolute minimum/max DC voltage that the switch can handle. I see a note in the data sheet which states that "Blocking capacitors are required if RF line potential is not equal to 0V" (page-5 pin description), does it mean the dc voltage cannot be lower than 0v in dc coupled application?
Basically, I need to know if I can conduct a DC signal and if so, what min and max DC levels are allowed before damaging the IC. Also, if there are better switches that could support stated application, please let me know.