Performance Limits, Design and Implementation of m m - W a v eS i G eH B TC l a s s - Ea n dS t a c k e d Class-E Power Ampli fiers Kunal Datta, Student Member , IEEE

Abstract

Design equations and performance limits of Class-E power ampli fiers at mm-waves, including the limitations imposed by active and passive devices in a given technology, are presented in this paper. A beyond nominal breakdown voltage Class-E design methodology for SiGe HBT power ampli fiers is proposed to gen- erate high output power while maintaining high Class-E ef ficiency. A mm-wave SiGe stacked Class-E architecture is also introduced to increase the overall voltage swing, with each series stacked device operating in the beyond nominal breakdown mode. The mm-wave beyond operation of SiGe HBTs has been demonstrated experimentally in an integrated 45 GHz Class-E power ampli fier fabricated in a 0.13 µm SiGe BiCMOS process with 20 dBm mea- sured output power at 31. 5% peak power-added ef ficiency (PAE). The series stacking of mm-wave Class-E power amplifier concept is also verified by fabricating double-stacked and triple-stacked SiGe HBT power ampli fie r si n0 . 1 3µ mS i G eB i C M O Sp r o c e s sw h i c h demonstrate a measured output power of 23.4 dBm at 41 GHz with peak PAE of 34.9%. High power, highly ef ficient, switching power amplifier unit cells presented in this paper can facilitate realization of efficient Watt-level mm-wave digital polar transmitters.