A GaAs upconverter MMIC with an automatic gain control amplifier for 1.9 GHz PHS

Abstract

A newly developed GaAs upconverter MMIC with an automatic gain control (AGC) amplifier is presented. The design objectives, considerations, problems, and their solutions are described. The circuit is designed for a 1.9 GHz radio-frequency transceiver for the Japanese Personal Handyphone System applications. The features of the upconverter are: (1) on-chip 50 /spl Omega/ impedance matching for all AC input and output signals; (2) a doubly balanced Gilbert cell and a two-stage AGC amplifier with matching circuits that provide 23.0 dB conversion gain, -39 dBc LO suppression, -23 dBc image suppression, and 30 dB gain control; (3) an adjacent channel power of -70 dBc, and (4) a die size of only 2.87 mm/sup 2/ (2.52 mm/spl times/1.14 mm).