Clover Shape Layout Technique in Switched Capacitor Power Amplifier for Improving Drain Efficiency

Abstract

In this paper, a new layout technique for improving drain efficiency of the switched capacitor power amplifier (SCPA) is proposed. To minimize the line length from the output capacitors to the output, capacitors and amplifiers are placed around the output pad. This reduces parasitic capacitances and resistances of the output line. Simulation result shows 3% improvement in the drain efficiency. The fabricated test chip achieves 24% drain efficiency at 7 dB back-off while delivering 11 dBm output.