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Cellular handset makers constantly strive for RF system solutions which offer a lower cost, that achieving stringent RF performance at low power consumption levels. Until recently, FDD operation and other tough RF specifications have left most CDMA applications still based on superheterodyne architectures in both transmit [1,2] and receive paths. In this paper, we describe a direct-conversion CDMA2000 transmit path IC with few external components and low current consumption, consistent with RF power output and performance.The CDMA2000 specifications pose several challenges for the transmitter design. First, the RF output must have precise, fine resolution power control over more than 80dB, ideally with a gain control characteristic that is nearly linear in dB, as this reduces the handset manufacturers' task in final calibration. Second, the design must balance power consumption with strict linearity requirements, while reducing the supply consumption at low output power levels. Studies show that output power in operation will most frequently be around 30dB below maximum; hence maintaining nominal bias currents for all output levels is wasteful.