CMX990 Datasheet | CML

Features - Single Chip RF Transceiver and GMSK Modem - IF, RF, Control and Synthesizer Stages - Selectable Bt = 0.27, 0.3 or 0.5 - Receiver Sensitivity -116d Bm at 8kbps - Full Mobitex patibility - Versatile Data Rates: 4kbps to 16kbps - Packet and Freeformat (Raw) Data - Low-Power, Low Profile, Low-Cost BOM Provisional Issue - 400MHz - 1GHz Radio Data Systems - Simple Parallel Interfacing - AGC Algorithm - RSSI Measurement - Flexible System Clocks - Suitable for EN 300 113, EN 300 220 and FCC CFR 47 Part 90 1 Brief Description A single-chip GMSK packet-data modem and RF transceiver, the CMX990 provides the majority of circuits and functions to implement a full-feature ‘wireless modem’ subsystem. The CMX990 can operate in RF ranges of 400MHz to 1GHz at data rates of 4 to 16 kbps and is fully Mobitex patible. With a minimum of external ponents and circuits, this half-duplex device provides on-chip: a flexible, formattable GMSK packet and free-format modem, a dual synthesiser, IF and RF stages for both Rx and Tx modes, and auxiliary ADCs and DACs for system control and monitoring. © 2008 CML Microsystems Plc GMSK Packet Data Modem and RF Transceiver This versatile GMSK modem is programmable to both packet and free-format data operations via an efficient task-oriented Rx and Tx format and mand structure, which is bined with data scrambling, interleaving and FEC and CRC capabilities. Rx data acquisition, extraction and tracking abilities, allied with Rx data quality feedback, allow the CMX990 to operate seamlessly in varying signal environments. Tx includes an internal vector modulator to accurately generate the modulation. This is then translated to the final frequency using an offset-phased locked loop. In the Rx path an image-reject mixer is provided to minimise external RF filtering requirements. The output of the mixer goes off-chip to allow the circuit designer flexibility in the choice of IF filter. The CMX990 then provides AGC functions and I/Q mix...