Hi
I have a differential amplifier - LTC6362 if it matters, part of a much bigger circuit. Each input (from a differential source) is through two series Rs with a C from their midpoint to ground, like a T, to provide some HF rolloff. It works just fine.
Of course, I could use a single half value C between the two midpoints and no ground connection.
+in --R--+--R-- +amp | C | GndGnd | C |
-in --R--+--R-- -amp
...or...
+in --R--+--R-- +amp | 1/2 C |-in --R--+--R-- -amp
Which is best? Cost is immaterial. My guess is best to avoid ground as the two Cs won't be exactly the same value, but a colleague disagrees, so other opinions are welcome.
Cheers