Hi all,

I am working on a common-source LNA with inductive degeneration.
For the input matching, I followed the standard approach:
Set the real part of the input impedance (Ldeg*gm/Cgs) to 50Ohm and then try to cancel the imaginary part (Cgs*(Lg+Ldeg)*w²-1)/Cgs*w with a series inductor Lg .

In my design, Cgs is very small (~15fF)  which results in a large Lg (>100nH).
Can I do something to obtain more reasonable Lg?

Thanks!

Thanks. I found the same statement in Razavi's RF microelectronics book