TABLE OF CONTENTS This part of the chapter gives examples of analogue and digital GaAs circuits which have been chosen to give the reader an appreciation not only of performances and techniques being used but also the growth in the GaAs industry during the last decade. The first of the following main sections deals with analogue microwave integrated circuits with emphasis placed on small-signal amplifiers, power amplifiers, voltage-controlled oscillators, phase-shifters, switches, mixers and complete subsystems such as an image rejection receiver and a phased-array transmit/receive module. The latter not only contains GaAs MMICs but also discrete FETs in hybrid circuits. The digital section again gives a number of examples of circuits showing in particular the rapid growth in the level of integration achieved over the last five years. These examples include a high speed word generator using BFL, a 4 kBit SRAM using DCFL and high-speed gate-arrays. Comparisons are made between the performance of reasonably complex existing state-of-the-art circuits in GaAs and Si.
There is no doubt that the area to have received most attention from MMIC designers is the small-signal amplifier. Following the first reported monolithic GaAs IC to employ MESFETs by Pengelly et al (1976) which was a single-stage design covering 8 to 12 GHz there has been a large activity in both narrow-band and ultra-broadband designs. All the broadband IC amplifier designs achieved early on used reactively-matched networks synthesized by treating the input and output equivalent circuits of the MESFET as series...
