The MAX2023 low-noise, high-linearity, direct upconversion/downconversion quadrature modulator/demodulator is designed for single and multicarrier 1500MHz to 2300MHz DCS 1800/PCS 1900 EDGE, cdma2000 , WCDMA, and PHS/PAS base-station applications. Direct conversion architectures are advantageous since they significantly reduce transmitter or receiver cost, part count, and power consumption as compared to traditional IF-based double-conversion systems. In addition to offering excellent linearity and noise performance, the MAX2023 also yields a high level of component integration. This device includes two matched passive mixers for modulating or demodulating in-phase and quadrature signals, two LO mixer amplifier drivers, and an LO quadrature splitter. On-chip baluns are also integrated to allow for single-ended RF and LO connections. As an added feature, the baseband inputs have been matched to allow for direct interfacing to the transmit DAC, thereby eliminating the need for costly I/Q buffer amplifiers.