Differential amplifier input impedance

[nuddin]

differential amplifier input impedance

Dear all, I am designing a differential amplifier using HEMT (not with OpAmp). This will be fed from a small loop antenna which senses near EM field over an IC/chip. I am working with Agilent ADS.

I donn't understand how to simulate/ calculate the input impedance of the differential amplifier.

Can anyone help me regarding the input impedance of differential amplifier / input matching of diff. amp?

Thanks in advance.

Nasir

 

[lladnar23]

input impedance of differential amplifier

Run an SParameter analysis on it in ADS and plot S11 which is the input scattering parameter.. That will tell you the real and complex portions of the input impedance...

 

[zhl_gs1980]

input impedance differential amplifier

how to run an SParameter analysis?

 

[nuddin]

impedance in differential amplifier

Thank you very much lladnar. It works and looks same as I got by using Vin/I_in!!