A monolithic GaAs DC to 2-GHz feedback amplifier

Resistive feedback in low-frequency FET amplifiers is an attractive method of simultaneously attaining gain flatness and excellent input-output VSWR over wide bandwidths. Combined with simple matching circuitry, the feedback approach allows the design of general-purpose utility amplifiers requiring much less chip area than when conventional matching techniques are used. The 1.5- by 1.5-mm chip described in this paper provides 10-dB ± 1-dB gain, excellent input and output VSWR, and saturated output power in excess of + 20 dBm, from below 5 MHz to 2 GHz. The noise figure is approximately 2 dB when biased for minimum noise, with an associated gain of 9 dB.