A K-band linear/normal/efficient tri-mode power amplifier in 0.18-um CMOS with body bias adoption

A fully integrated K-band linear/normal/efficient tri-mode power amplifier was designed and fabricated in 0.18-um CMOS technology. By using the triple cascode structure accompanying the appropriate body bias adoption, the proposed power amplifier can switch to linear mode, normal mode, or efficient mode easily according to the conditions of usage. In the efficient mode, the power consumption is reduced by 50 % compared to the normal mode without gain compromise. In the linear mode, the power amplifier achieves the minimum 1.1 dB power difference between the P_sat and OP_1dB, and the minimum 0.7 % PAE difference under P_sat and OP_1dB power conditions. To the best of the author's knowledge, this is the first demonstration of triple cascode structure accompanying the body bias adoption and achieving the outstanding minimum (P_sat-OP_1dB) among the reported CMOS K-band PA.