i am designing an active high pass filter. suppose the cut off of the filter is 100kHz, the non-ideal opamp poles is making it like a bandpass. How to make it a perfect high pass. Is it possible?
krishmaniac,
No, it is not possible. The best you can do is selct an op-amp with a cutoff frequency that is well above (i.e >10X) the highest frequency of interest.
Regards,
Kral
A perfect High pass filter is not possible, because the open loop frequency response fo the op amp is a Low pass filter.
If you design a high pass filter joined with the frequency response gives you a band pass filter.