Front-End IC Serves Dual-Band Phones

Integrating 800-MHz cellular and 1900-MHz PCS low-noise amplifiers and down-conversion mixers, the SA3600 is a front-end receiver IC targeting the next wave of dual-band, multimode digital cellular phones. The IC's local-oscillator frequency doubler, I/O buffer amplifiers, matching circuitry and control-mode logic reduce external glue components. The cellular-band LNA and mixer consume 10 mA from a 2.7V supply; the PCS-band LNA and mixer consume 14 mA, which is said to be 35% better than the best GaAs RF front-end ICs. At 881 MHz, the IC provides 24 dB of gain, a 2.6 dB noise figure and –10.5 dBm input IP3. At 1960 MHz, the chip delivers 22 dB of gain, a 3.1-dB noise figure and –10.5 dBm input IP3.