A 2.2-V operation, 2.4-GHz single-chip GaAs MMIC transceiver for wireless applications

A 2.2-V operation, single-chip GaAs MMIC transceiver has been successfully developed for 2.4-GHz-band wireless applications such as wireless local area network terminals. The chip is fabricated using a planar self-aligned gate field-effect transistor. To generate sufficient negative voltage for gate-biasing and to enhance switch power handling capability under a 2.2-V supply, a newly designed negative voltage generator with a voltage doubler (NVG-VD) and a switch control logic circuit are integrated on the chip, together with a power amplifier, a transmit/receive switch, and a low-noise amplifier. The NVG-VD is designed to produce both a 3.3-V positive step-up voltage and a -2.1-V negative voltage under 2.2 V in operation voltage. Biased with these outputs, the logic circuit accommodates high power outputs of over 25 dBm with a low operating voltage of 2.2 V in transmit mode, With a 2.45-GHz modulated signal based on IS-95 standards, a 21-dBm output power and a 33% efficiency are obtained at a ±1.25-MHz-offset adjacent channel power rejection of -45 dBc. In receive mode, a low-noise amplifier achieves a 1.8-dB noise figure and an 11-dB gain with a 3.0-mA current. This transceiver enables significant size and weight reductions in 2.4-GHz-band wireless application terminals