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Can a capacitor or inductor change into microstrip?

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liuzhili

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A schematic of A RF MMIC design with some capactors and inductors,especially in Match Network,Can these capacitors or inductors change(transform) to microstrip to a layout? How to? Is there any formulas?
thank you
 

flatulent

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impedance transformations

There are probably as many ways to design an impedance transforming network as there are designers. There are certain ways that minimize cost and other useful engineering parameters that designs are judged by. The reason the MMIC you saw used lumped parts was probably the cost factor. The transmission line method would have taken up more surface area. The other advantage of lumped elements is that filters made from them have just the designed passband. Transmission line filters have an infinite number of alternating pass and stop bands that are approximately harmonically related.
 

lcg22

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liuzhili said:
A schematic of A RF MMIC design with some capactors and inductors,especially in Match Network,Can these capacitors or inductors change(transform) to microstrip to a layout? How to? Is there any formulas?
thank you
I think you may consult Gonsalez's book, and other RF books in regard to transmission line and matching network. To my knowledge, transmission line can realize any value of reactance, however, as flatulent has stated, it do has lots of disadvantages.
 

chiara

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maybe

if you have a schematice of MMIC with lumped devices
(spiral inductors & MIM capacitors), It's not a good idea to change
them with microstrip component.

check first the working freq range of the circuit
and the wave length of the frequency....

if your purpose is to change your own design with lumped component
to with distributed components
then lean to the optimizer of your design tool.

lumped component to distributed component 1 to 1 mapping
may not bring you a satisfactory performance
except for a narrow band application
 

jupitorcuu

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I think maybe lumped comp is useful in RF frequency,because the space for the same function TRline needed more.
Impedence accuracy also is a problem
 

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