pa driver 0.18um
Hi Guys:
I had designed the first stage class-A fully differential PA driver, in 0.18um CMOS technology using thick oxide transistors. The PA is to provide a power amplification of 18dBm for an input range of -25dBm to +2dBm. The differential PA driver consumes 20mA of current. The PA is realized using a capacitor tapped input-output matching network. The output power in comparison to the input power plot shows good preliminary amplification in proportional to its voltage amplification. However it is said that in PA the amplification occurs in the current. The output current sensed at the output of the matching network doesn't show any current amplification. Since :
Pout= [(ILOAD^2)/2]*RLOAD
Where ILOAD is the peak current at the output and RLOAD is 50Ohms. I hope anyone could explain the reliability of the formula given and shed some light of the issue of current attenuation, faced here. Thanks in advance.
Rgds