0.18μm CMOS Power Amplifier For 5GHz Wireless LAN Systems

The growing popularity of Internet demands high data rate wireless local area network (WLAN). Using the unlicensed national information infrastructure (U-NII) band, WLAN systems can provide data rates up to several tens of megabits per second.The radio frequency (RF) integrated circuit is the design bottleneck of the WLAN systems. The viable IC technology for RF circuits continues to change. Performance, cost, and time to market are three critical factors influencing the choice of technologies in the competitive RF industry. Supported by the enormous momentum of the digital market, CMOS devices have achieved high transit frequencies. In the resent years, RF CMOS has suddenly become the topic of active research.This paper presents the design of a 5-GHz CMOS power amplifier based on a 0.18um CMOS technology for IEEE 802.11a WLAN systems. Simulation results and layout are provided. It is implemented in three differential stages. With a supply voltage of 3.3V, its gain is 23.7dB, Pout,1dB=21.8dBm, the maximum Power Added Efficiency(PAE) is 15%. It can be expected to be used in IEEE 802.11a WLAN systems.Firstly, architectures and specifications of the RF transmitter are discussed. And the category of WLAN has been given. Secondly, the circuits and specifications of all kinds of power amplifiers are focused. Then, It introduces the details of the design from six aspects, including cells dividing, analysis of stability, and design of matching network, design of bias network, design of main amplifier and design of ESD. The simulation results have also as been presented. Next, the realization of the layout of the power amplifier is given. And some modify of the layout from manufactory has also been mentioned. Finally, the test of the chip has been introduced. And the analysis of the test results also has been given.