sbridger
commented
1 year ago Given that the switch R is 5 ohms, it is likely to be better to just use a single switch at each end instead of paralleling them up. In that case there would be a couple of options for the unused muxes:
- use the unused muxes to decode and drive the diodes, thus eliminating the need for extra control lines
- If you wanted to minimise the BOM and not add diodes, then the 2 extra muxes could be grounding two of the three unused filters
I would expect that to maximise performance you should add diode rf switches inside each filter segment, that short the unused ones to ground. If you consider a filter board that uses relays, the NC contact at both end of each filter does this. Otherwise your high frequency filter will bypass the LF one due to track/pad/switch crosstalk.