High-speed analog-to-digital conversion with GaAs technology: prospects, trends and obstacles

The authors addresses the prospects for widespread use of GaAs technology for analog-to-digital (A/D) conversion, the technological and design trends for improved A/D realizations, and the obstacles to the realization of higher speed and resolution. It is noted that GaAs MESFET and HBT (heterojunction bipolar transistor) technology promise an increase in sample rate and achievable resolution for A/D conversion compared to silicon technology, if a number of technological and design limitations can be overcome. GaAs MESFET technology is relatively mature, but currently suffers from poor threshold uniformity, 1/f noise, and hysteresis. GaAs HBT technology possesses few of the limitations of MESFET technology, but the achievable level of integration is still quite low.<>