An 8-Watt 3.5 GHz power amplifier with tunable matching

A high power 3-stage, S-band power amplifier MMIC implemented with a partially matched output stage is presented. This MMIC PA achieves 39 dBm output power and greater than 25% power added efficiency using 0.6 /spl mu/m PHEMT technology. Small-signal performance matches very well with modeled predictions. The amplifier is exceptionally stable under varying loads, has a bandwidth of several 100 MHz and is easily matched and tuned about the 3.5 GHz band with a simple output matching technique using chip caps, bond wires and duroid transmission lines.