A 1.7 GHz-to-3.1 GHz fully integrated broadband class-E power amplifier in 90 nm CMOS

The design of CMOS power amplifiers (PAs) is still a challenging task. In this paper, a broadband amplifier for wireless applications in a 90 nm CMOS process is presented. The PA uses class-E topology to exploit its soft-switching property for high efficiency. The differential amplifier is based on a finite DC-feed inductance concept and includes an on-chip output balun. The circuit has been integrated on one die measuring 1600 µm × 1200 µm. The amplifier has been optimised for operation from 1.7 GHz to 3.1 GHz. The postlayout simulations with a 2.5V supply, indicate that the amplifier is capable of delivering 24.6dBm of output power with an associated power gain of 7.6 dB and more than 38.5% power added efficiency over a wide bandwidth. The frequency range covers GSM, UMTS, WLAN, bluetooth and LTE standards. A peak power added efficiency of more than 49.5 %, output power of 26.8dBm and a gain of 9.8 dB is obtained at LTE i.e. 2.55 GHz.