A 2.4GHz monolithic SiGe power amplifier for Wireless-LAN transceiver

A high-linearity power amplifier (PA) for 2.4 GHz Wireless-LAN transceiver is presented. The PA is designed and implemented using a 0.18 um SiGe BiCMOS process. An on-chip adaptive linearizer is comprised of a base-emitter diode of the bias transistor and a bypass capacitor with almost no increase in die area and no extra dc consumption. Besides the linearization function, the active biasing circuit is also temperature-insensitive with simple structure. Including all matching circuits and biasing circuits, the die area of the fully integrated PA is 1.2 mm * 1.1 mm. Temperature simulation indicates the variation of power gain is less than 1.6dB from 20°C to 80°C. The second-order and third-order LMD are less than -30.9 dBc and -34.5 dBc when the output PI dB has been reached. With 3.3 V supply, the PA achieves max PldB of 23.2 dBm and a power added efficiency (PAE) of 21.3%.