The AD7013 is a complete low power, CMOS, TIA IS-54 baseband receive port with single +5 V power supply. The part is designed to perform the baseband conversion of I and Q waveforms in accordance with the American (TIA IS-54) Digital Cellular Telephone system. The receive path consists of two high performance sigma-delta ADCs, each followed by a FIR digital filter. A primary and auxiliary set of IQ differential analog inputs are provided, where either can be selected as inputs to the sigma-delta ADCs. Also, a choice of two frequency responses are available for the receive FIR filters; a Root-Raised-Cosine filter for digital mode or a brick wall response for analog mode. Differential analog inputs are provided for both I and Q channels. On-chip calibration logic is also provided to remove either on-chip offsets or remove system offsets. A 16-bit serial interface is provided, interfacing easily to most DSPs. The receive path also provides a means to vary the gain of the receive path.