I have a question if somone could help.
I am supposed to design a filter circuit for school. I have chosen to use an op-amp because i have used them many times on my own.
My question is: the design says the the output impedence of the previous stage will be 100k ohms. I am assuming that my filter needs to match that value to allow maximum transfer of the signal.
So, my op-amp circuit has to have an input impedance of 100k ohms. So do i achieve that by having a 100k ohm resistor at the inverting input (assuming inverting amp)? or do i have a 100k shorted to ground where the signal comes in?
OR... do i not need to worry about impedance matching? Should i be satisfied that the really high input impedance of the opamp will not "load" the previous stage?
Sorry for the long post, any help appreciated.
thanks