Hi baab,
Quote:Hi,
I want to ask for help again. Please confirm if my understanding is correct.
+ First, I need to calculate load resistance based on the formula:
P = VDD2/(2Rload)
nope you are not correct. This formula applies if you are designing a power amplifier. From your system diagram, you are clearly not designing a power amplifier. You are simply designing an amplifier that works at RF.
In fact from the paper you attached, you are really designing an LNA. You should concentrate your reading on LNA design. Quote:+ With the load calculated above, put it into the circuit and sizing the component to get the output power.
don't use the load calculated from above.
1. For a 50 dB gain amplifier your will need at least 2 but more likely 3 stages.
2. You probably have a power consumption specification. This will roughly determine how much gm each stage can have. From there, you can calculate the load impedance you need at each stage to get 50 dB gain.
3. As it is a multi-stage design, you will need to optimize the gain distribution to get the best tradeoff between noise and linearity. You also need to pay careful attention to stability.
However, in the paper you sent, the RF amplifier has a gain of only 13 dB. This is a much more reasonable number than the 50 dB gain you seem to be designing. Why do you want such high gain?Aaron