I am designing a differential LNA(two outputs) with CG-CS cascode topology in ADS. I got s(21) -19 dB and s(31) +9 dB. But when i have connected external 3 port balun, i got 8 db of gain. I am confused, what should i take as gain that is whether it is magnitude addition of two ports gain which comes out to be 27 or balun's 8 dB GAIN.
when i did transient analysis with balun output and calculated gain with 20 log(vout/vin), i got max peak gain of 28 db.
PLS HELP.
You got 2 ports, where is the third one ??What does it mean "ports gain" ??
Sorry, have you ever designed any circuit in ADS ??? ( or in any environment ) If you haven't,please start simpler ones.
Go through step-by-step to learn consistantly.
actually, i have connect external balun for S11,S22,S21,S12 results and later I have remove this balun and connected two output terminals.
I want to ask that in these two cases i got different gain result, so which gain result is correct,
case 1 with external balun--- gain(S21)= 8.3 dB MAX
CASE 2 with 3 terminals-- gain(S21)(RIGHT SIDE)=9 dB and gain(S31)(LEFT SIDE)= -19 dB. Whether i add these two gain S21+MAG(S31).