XRT73L00A Datasheet | Exar

DESCRIPTION The XRT73L00A DS3/E3/STS-1 Line Interface Unit is an improved version of the XRT73L00 and consists of a line transmitter and receiver integrated on a single chip and is designed for DS3, E3 or SONET STS-1 applications. XRT73L00A can be configured to support the E3 (34.368 Mbps), DS3 (44.736 Mbps) or the SONET STS-1 (51.84 Mbps) rates. In the transmit direction, the XRT73L00A encodes input data to either B3ZS (for DS3/STS-1 applications) or HDB3 (for E3 applications) format and converts the data into the appropriate pulse shapes for transmission over coaxial cable via a 1:1 transformer. In the receive direction the XRT73L00A performs equalization on ining signals, performs Clock Recovery, decodes data from either B3ZS or HDB3 format, converts the receive data into TTL/CMOS format, checks for LOS or LOL conditions and detects and declares the occurrence of line code violations. The XRT73L00A also contains a 4-Wire Microprocessor Serial Interface for accessing the on-chip mand registers. FIGURE 1. BLOCK DIAGRAM OF THE XRT73L00A E3 S T S -1 /D S 3 H o s t/(H W ) FEATURES - Incorporates an improved Timing Recovery circuit and is pin and functional patible to XRT73L00 - Meets E3/DS3/STS-1 Jitter Tolerance Requirements - Full Loop-Back Capability - Transmit and Receive Power Down Modes - Full Redundancy Support - Contains a 4-Wire Microprocessor Serial Interface - Uses Minimum External ponents - Single +3.3V Power Supply - 5 V Tolerant pins - -40°C to +85°C Operating Temperature Range - Available in a 44 pin TQFP package APPLICATIONS - Interfaces to E3, DS3 or SONET STS-1 Networks - CSU/DSU Equipment - PCM Test Equipment - Fiber Optic Terminals - Multiplexers RLO L EXCLK IC T R C L K IN V R T IP R R IN G AGC/ E qualizer S licer C lock R ecovery RCLK1 Invert L C V /(R C L K 2 ) R E Q D IS P eak D etecto r LO S D etector D ata R ecovery H D B 3/ B 3Z S D ecode r RPOS RNEG LOSTHR SDI S D O /(L C V ) S C lk CS REGRESET D R /S R S erial P rocesso r...