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Design >> RF Design >> multi-stage PA matching?
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Message started by email_gz on Dec 12^th, 2007, 6:24pm

Title: multi-stage PA matching?
Post by email_gz on Dec 12^th, 2007, 6:24pm

Hello all:
I have a question about multi-stage PA matching.All cascade amps are lumped parameter devices without transmission line. So should I must design impedance matching net from one inner amp stage to the next inner amp stage ? Also if I don't consider the inner stage impedance matching at all, Would it bring about stability problem?
Thanks:)

Title: Re: multi-stage PA matching?
Post by Ian on Dec 17^th, 2007, 2:33am

For on-chip design, the inter-stage impedance matching is probably not needed, as long as you could get the voltage swing you want. For the stability, it's important to decouple the gate of cascode transistor and supply with big capacitors. Also, take care of the ground bounce for the multi-stage design.

Title: Re: multi-stage PA matching?
Post by email_gz on Dec 19^th, 2007, 5:58pm

Helllo Ian:
Thanks very much for your significant reply!