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Design >> RF Design >> Recommendation of Discrete Cost Effective Balun
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Message started by pancho_hideboo on Mar 13^th, 2008, 3:31am

Title: Recommendation of Discrete Cost Effective Balun
Post by pancho_hideboo on Mar 13^th, 2008, 3:31am

Hi.

I'm now studying cost effective balun using discrete L and C.

My TX PA outputs are open drain of differential pair.
So I have to feed Vdd via external inductor or resistor.

And I have to share TX differential pins with RX differential LNA inputs.

Is there any good cost effective balun structure using discrete L and C for this purpose ?

Title: Re: Recommendation of Discrete Cost Effective Balu
Post by ACWWong on Mar 13^th, 2008, 3:46am

An LC "bridge" configuration should be ok if you only need narrow band, and the LNA input Z and TX output Z are similiar (i.e. same balun impedance tranform useable for both rx and tx modes)

i quick google gives
http://www.odyseus.nildram.co.uk/RFMicrowave_Circuits_Files/Balun%20Design.pdf
and the first method is the lumped LC configuration i'm suggesting.

hope it helps

Title: Re: Recommendation of Discrete Cost Effective Balu
Post by pancho_hideboo on Mar 14^th, 2008, 1:03am

Thanks for valuable information.