Study And Design Of RF Driver Amplifier

Power amplifier is a key component of the transmitter,the function of power amplifier is amplify high frequency signal to the necessary power to meet the transmitting antenna or load requirements.The driver amplifier in the input of the power amplifier,which role is to provide adequate input power,to drive the power amplifier output enough power.This thesis designs the driver amplifier based on CMOS technology,which is the key block in transmitter's front-end.In recent years,the application of wireless communication is increasingly broad. The direction of it is higher frequency and wider band.CMOS circuits are perfect for they have low power,low cost and can be easily integrated.At the same time,in order to achieve system on a chip(SOC),use CMOS technology is the development direction.The driver amplifier is based on the JAZZ 0.35μm CMOS process,and use Cadence tools to design the frequency from 1 GHz to 2 GHz wide-band driver amplifier. The CMOS driver amplifier work under a 3.3 V power supply,realizes from the single-ended input and differential double-ended output,input impedance of 75Ω, output impedance for 50Ω.This circuit has two stages.The first-stage is the cascode structure,to achieve single-ended input,single-ended output,taking into account the wide-band matching principle,design a second-order Butterworth filter as input matching network,and use shunt-peaked amplifier to expand bandwidth;second-stage is the differential structure, to achieve single-ended input,double-ended output,here use Balun to make the differential output gain equal and phase difference 180°in the frequency range,and designs parameters to match the 50Ωoutput impedance.Finally the two output ports gain of the circuit in the frequency of 1 GHz, respectively,17.83dB,17.78dB,1.5GHz,respectively,19.54dB,19.77dB,2GHz, respectively,16.50dB,17.17dB.From 1 GHz to 2 GHz frequency range,the input and output impedance matching,the phase difference of two output ports is±1dB,the gain difference is 180±1°.The noise factor NF=4.13dB in the 1GHz,from 1GHz to 2GHz stability factor K＞1.The input 1dB compression point is -8.40dBm,output is 8.4dBm. The input third-order intercept point is 1.36dBm,output is 19.1 dBm.