In this paper, ultrahigh power-added efficiency is reported for AJGaAs/GaAs HBT's operating at 10 GHz in common-emitter (CE) and common-base (CB) modes. A record high 67.8% power-added efficiency with 11.6 dB associated gain was achieved with a CE HBT at a CW output power of 0.226 W, corresponding to a power density of 5.6 W/mm. With a CB HBT, 62.3% power-added efficiency with 11.85 dB gain and 0.385 W total CW power was demonstrated. Details of the operation of both CE and CB HBT's are described and compared. Current gain, stability, near class B operation, and power saturation characteristics are discussed. Differences from FET behavior are highlighted.
|Number of pages||10|
|Journal||IEEE Transactions on Microwave Theory and Techniques|
|State||Published - 1 Jan 1990|