Design Of 2.4~2.5GHz Voltage Mode Doherty Power Amplifier Based On 22nm CMOS Process

The RF power amplifier is located at the end of the transmitter,which is the most important component of the wireless communication system,and the maximum power consumption in the entire transmitter system.Therefore,the efficiency of the power amplifier should be improved,and the service life of the equipment should be extended.With the development of wireless communication system technology,in order to meet the requirements of high-rate transmission of big data,RF power amplifiers with high-efficiency,high power and high linearity have always been a hot spot for scholars.This thesis uses a 22nm CMOS process to design a 2.4～2.5GHz voltage mode Doherty power amplifier（DPA）applied to the wireless communication system.The power amplifier is implemented based on the active load traction principle.It mainly includes a main power amplifier,auxiliary power amplifier,input matching network,and an output transformer matching network.The main power is working in class AB,and the auxiliary power amplifier works in Class C.Main power amplifier and auxiliary power amplifier are both implemented with a differential Cascode structure.Main power amplifier uses capacitor compensation technology,in order to improve the linearity of the AB class power amplifier.Input matching network adopts a loss T-type network structure to ensure that the stability of the circuit can complete the input matching.The output matching network uses a two-transformer voltage mode structure.In order to compensate for the effect of process angle changes on circuit performance,the bias circuit uses voltage dividing structure of the transistor and resistance.The thesis gives circuit design and analysis,pre-simulation results,layout design and optimization and post simulation results.The post-simulation results show that the operating frequency band is 2.4～2.5GHz under the TT process Angle,the temperature is-40～85℃,and the power supply voltage is 3.3V.The saturation output power of power amplifier is 30.35d Bm,the output power of power amplifier at 1d B compression point is 27.59d Bm,the peak power additional efficiency is 42.67%,the power additional efficiency is 33.57%at 6d B back of from P_sat and the output 3rd intercept point is 40.17d Bm.The layer size is 1200μm×1120μm,and the core size is 953μm×898μm.The voltage mode Doherty power amplifier designed in this thesis meets design indicator requirements and can be applied in the RF communication system.