Design of 5 GHz-Band Power Amplifier with On-Chip Matching Circuits Using CPW Impedance (K) Inverters

This Letter employs transmission-line theory for the impedance-matching circuits for a single-chip power amplifier (PA) and verifies for 5GHz-band wireless LAN (IEEE 802.11a) applications. The presented matching circuits are composed of conductor-backed coplanar waveguide (CPW) meander-line resonators and impedance (K) inverters. One of the advantages of the presented circuits is that it can save on-chip space occupied by the matching circuits compared to that using the spiral inductors, thus reducing the cost. The prototype chip, which consists of PA and matching circuits, is designed employing the presented theory and fabricated. A few of the measured results to verify the design theory are presented.