EFFICIENCY IMPROVEMENTS FOR MULTI-STAGE POWER AMPLIFIERS

Efficiency improvements for multi-stage power amplifiers are described. In one example, a power amplifier includes a driver amplifier formed on a first semiconductor die using a first semiconductor fabrication process, an output amplifier formed on a second semiconductor die using a second semiconductor fabrication process, and an inter-stage matching network formed between the driver amplifier and the output amplifier. The first semiconductor fabrication process is a lower voltage process and the second semiconductor fabrication process is a higher voltage process. The use of the two different fabrication processes leads to a number of advantages, including the simplification of the inter-stage matching network, increased radio frequency bandwidth, and improved line-up efficiency among the stages of the power amplifier.