A millimeter-wave Class-E tuned power amplifier is realized in 0.13im SiGe BiCMOS technology. To accomplish switching-mode operation at 60GHz, the transmission line input impedance transformation network provides a low real source impedance rather than optimum power match. The prototype IC is a single-ended single stage design that operates from a 1.2V supply and employs an area of 0.98mm2. Measurement results show a saturated output power >11.ldBm with peak PAE>15% from 55-60GHz. At 58GHz it achieves a peak PAE of 20.9%, peak power gain of 4.2dB and saturated output power of 11.7dBm.