Re: Matching a monolithic xtal filter

On Sep 11, 11:15 am, Joerg <notthisjoerg...@xxxxxxxxxxxxxxxxxxxxx>
wrote:
Tom Bruhns wrote:
....
how much you can do. At a 45MHz center frequency, without going
really overboard with the LC filter, you probably will end up with a
3dB bandwidth at least a couple MHz wide. To do much better while
keeping the filter loss low requires coils with high Q, which get
physically large.

That's where the old concept of the Q-multiplier comes in. After that it
only boils down to how good you are able to control the CF of a resonant
circuit up front. But shhht, don't tell anyone. The younger lads out
there don't have the foggiest idea what that is.

Ouch! Not around my designs, thank you. :-(

[For the uninitiated: just stay away from them.]

Cheers,
Tom




.

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