1.2V CMOS 1-10GHz Traveling Wave Amplifiers Using Coplanar Waveguides as On-Chip Inductors

Abstract — The feasibility of using standard 0.18µm CMOS technology for low cost wideband radio frequency integrated circuits (RFICs) at ~10GHz is demonstrated. Two different designs of coplanar waveguides (CPWs) have been fabricated for loss comparison and the low-loss design has been identified. The measured loss for the 0.5mm long low-loss design is 0.32dB at 10GHz. A monolithically integrated four-stage traveling wave amplifier (TWA) with n-FET cascode gain cells is proposed, with CPWs as the on-chip inductive elements, and is being fabricated. Simulated results indicate a 10dB gain at 1GHz and unity-gain frequency of 12GHz. This TWA is also compared with measured results of a previously reported five-stage TWA with single n-FET gain cells. A new design for a distributed oscillator using a TWA is proposed and is currently being fabricated. Index Terms — CMOS RFIC, microwave integrated circuits, coplanar waveguides, MOSFETs, traveling wave amplifiers, temperature effects, distributed oscillator. I