Abstract-Two different frequency doubling power amplifiers have been measured, one with differential and one with singleended input, both with single-ended output at 60 GHz. The amplifiers have been implemented in a 1p8M 130-nm CMOS process. The resonant nodes are tuned to 30 GHz or 60 GHz using on-chip transmission lines, which have been simulated in ADS and Momentum.The measured input impedance of the single-ended PA is high at 250 Ω, and the differential input is similar, making the PA a suitable load for an oscillator in a fully integrated transmitter. The single-ended and differential input PA delivers 1 dBm and 3 dBm, respectively, of measured saturated output power to 50 Ω, both with a drain efficiency of 8%.