Re: best op-amp for 10.7MHz BP filter

Hello Meindert,

Why ? I agree a ceramic filter would be good if you need a few to a few 10's
of kHz bandwidth. But why should you use LC circuits? Because everybody used
to do it that way or is an LC filter still better than a modern 1GHz GBW
opamp with a few cap's and R's? Just curious..

Because LC is a whole lot cheaper and you can achieve a much better filter performance and group delay flatness. With your wide BW spec it would boil down to two filters in series. One high pass and another one low pass.

Today it would be possible to do this with opamps but that doesn't mean it would make economical sense. Actually, it doesn't ;-)

Besides cost and size there is another drawback of opamp filters at high frequencies. They consume a whole lot of power.

Regards, Joerg

http://www.analogconsultants.com
.

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