Difference between 50ohm board and 75 ohm board (Help needed)

To all pros and genius out there,


I have no idea with the different between 50 ohm board and 75 ohm board.
I just know the major different is the conductor width and the gap.
other than that, assume my circuit have external inductor and capacitor.
Do i need to change to value of them when i change from 50 ohm to 75ohm with balun added ?


Very appreciate your response and help
Thank you

Track size and thickness to ground plane determine impedance for a standard dielectric constant=4~4.2 . So just change track width if you are following stripline and microstrip design for microwave. Otherwise for lower f . it wont matter as much. Many Zo calculators online

the board i using is conductor backed coplanar waveguide
My dielectric constant is 2.468
freq which i using is 2GHz

then choose track width according to your parameters

I know.My question is regarding the external components like inductor and caps, do i need to change their value when i changing termination impedance from 50ohm to 75ohm ?

The trace geometry will of course need to change.

As for the caps and inductors, it depends on their function. If they are matched to the characteristic impedance of the signal path, like a filter would be, then the values will need to be adjusted. If they are not matched to the characteristic impedance, like say decoupling caps, then they will not need to be changed.

no idea what your LC circuit is doing but that will be affected by change in Zo(f)