Development of highly dense four-stage flat-gain 1-W 6-18-GHz MMIC power amplifier chip

A state-of-the-art dual-channel four-stage MMIC power chip operating over C-X-Ku bands has been produced. The chip, which is only 4.35 mm×5.1 mm, operates over 6-17 GHz with very small gain ripple. At 25°C each one of its channels provides 29.5±0.5 dBm at 2-dB compression (2 dBc) from a small-signal gain of 19.5±1.5 dB. The drain bias is 7 V. and the power added efficiency is 11-14%. At 85°C, power and gain decrease by 0.5-1 and 3.5-4 dB, respectively. The design was iterated once to produce an all-monolithic amplifier chip that operates over the full 6-18-GHz frequency band and provides more than 1 W at 18 GHz. The architecture and size were maintained in the iterated design. The excellent power and gain ripple performances of the C-X-Ku chip extended to 18 GHz with a small-signal gain reduction of 0.5-1 dB. The chip is designed for use with inputs and outputs coupled externally for additional 2-2.5 dB of power. Excellent performance over 6-18 GHz was achieved using Lange couplers on 10-mil alumina