MAX2850,pdf datasheet ( 4-chan

The MAX2850 is a single-chip, 4-channel RF transmitter IC designed for 5GHz wireless HDMI applications. The IC includes all circuitry required to implement the complete 4-channel MIMO RF transmitter function and crystal oscillator, providing a fully integrated transmit path, VCO, frequency synthesis, and baseband/control interface. It includes a fast-settling, sigma-delta RF fractional synthesizer with 76Hz frequency programming step size. The IC also integrates on-chip I/Q amplitude and phase-error calibration circuits. Dynamic on/off control of four external PAs is implemented with programmable precision voltages. A 4-to-1 analog mux routes external PA power-detect voltages to the RSSI pin.

On-chip monolithic filters are included for transmitter I/Q baseband signal reconstruction to support both 20MHz and 40MHz RF channels. The baseband filtering and Tx signal paths are optimized to meet stringent WHDI requirements. The upconverter local oscillator is coherent among all the transmitter channels.

The reverse-link control channel uses an on-chip 5GHz OFDM receiver. It shares the RF synthesizer and LO generation circuit with the MIMO transmitters. The receiver includes both an in-channel RSSI and an RF RSSI.