The MAX2842 single-chip, direct-conversion, zero-IF RF transceiver IC is designed for 3GHz NLOS wireless broadband MIMO systems. It has two transmitters and two receivers, with differential 100Ω RF inputs and outputs. The IC includes all circuitry required to implement the complete RF transceiver function, providing fully integrated receive paths, transmit path, VCO and tank, frequency synthesis, and baseband/control interface. It includes a fast-settling sigma-delta RF fractional synthesizer with ~25Hz frequency step size. The IC also integrates an on-chip AM detector for measuring transmitter I/Q imbalance and LO leakage. An internal transmit-to-receive loopback mode allows for receiver I/Q imbalance calibration. The IC supports full duplex mode of operation for external loopback.
The MAX2842 completely eliminates the need for external SAW filters by implementing on-chip programmable monolithic filters for both receiver and transmitter, for channel bandwidths from 3.5MHz to 10MHz. The baseband filtering Rx and Tx signal paths are optimized to meet stringent noise figure and linearity requirements. The transceiver is housed in a small 56-pin TQFN, 7mm x 7mm, leadless plastic package with exposed paddle.