if Vcc=2.7V , Idc=1mA so Imax=2mA (two times of Idc for symmetric operation) and we assume Vsat=0.25V
Ropt=2*(2.7-0.25)/2E-3=2450 Ohm.
With this Ropt you'll find 1.225mW output power that is not "really" power amplifier..
Load Line theory is only used to predict "range of load impedance".In other hand, there are many parasitic factors that influence the operation. So this design should be simulated in a Load Pull featured simulator with high accuracy nonlinear models.
t think if you have a nonliner model,you should try load pull methods to find
the best impedance of the Ropt.
ansoft designer,ads, mwo these cad tools all have this method.
good luck to you.
I use TSMC 0.25um process , they don't have large signal model.
1. So according BigBoss Ropt=2.45k and match to 50 Ohm ,
2. I also run load-pull 1db contour , the Ropt=113+j271 @Ropt=2.7k
and match to 50Ohm
3. set Ropt=300Ohm
The reult is Ropt=300Ohm have max power then 113+j271 and 2.7K.
so formula is correct ??? Or I'm miss the message .
i had try the method that BigBoss and molloy suggestion, Ropt=2450 have max amplitude and power ..
I have another question
1. the nolinear model is equal large signal model ??
2. when run 1db contour need input matching ?
3. I don't have large signal model can run 1db contour ?