XRT7300 E3/DS3/STS-1 LINE INTERFACE UNIT MAY 2011 REV. 1.1.2 FEATURES GENERAL DESCRIPTION Meets E3/DS3/STS-1 Jitter Tolerance Require- The XRT7300 DS3/E3/STS-1 Line Interface Unit is ments designed to be used in DS3, E3 or SONET STS-1 ap- plications and consists of a line transmitter and re- Full Loop-Back Capability ceiver integrated on a single chip. Transmit and Receive Power Down Modes XRT7300 can be configured to support the E3 Full Redundancy Support (34.368 Mbps), DS3 (44.736 Mbps) or the SONET Contains a 4-Wire Microprocessor Serial Interface STS-1 (51.84 Mbps) rates. Uses Minimum External components In the transmit direction, the XRT7300 encodes input Requires Single +5V Power Supply data to either B3ZS (for DS3/STS-1 applications) or -40C to +85C Operating Temperature Range HDB3 (for E3 applications) format and converts the data into the appropriate pulse shapes for transmis- Available in a 44 pin TQFP package sion over coaxial cable via a 1:1 transformer. APPLICATIONS In the receive direction the XRT7300 performs equal- Interfaces to E3, DS3 or SONET STS-1 Networks ization on incoming signals, performs Clock Recov- CSU/DSU Equipment ery, decodes data from either B3ZS or HDB3 format, converts the receive data into TTL/CMOS format, PCM Test Equipment checks for LOS or LOL conditions and detects and Fiber Optic Terminals declares the occurrence of line code violations. Multiplexers The XRT7300 also contains a 4-Wire Microprocessor NOTE: This Device is Protected by US Patent 6,157,270 Serial Interface for accessing the on-chip Command registers. FIGURE 1. BLOCK DIAGRAM OF THE XRT7300 E3 STS-1/DS3 Host/(HW) RLOL EXCLK ICT RCLK2INV RTIP RCLK1 AGC/ Clock Slicer Invert RRING Equalizer Recovery LCV/(RCLK2) Peak REQDIS Data HDB3/ RPOS Detector Recovery B3ZS RNEG Decoder LOS Detector LOSTHR SDI DECODIS RLOS SDO/(LCV) Serial Processor LLB SClk Loop MUX Interface RLB CS ENCODIS REGRESET TAOS TPDATA TTIP HDB3/ Transmit Pulse B3ZS TNDATA Logic Shaping Encoder Duty Cycle Adjust TClk TRING TXLEV MTIP Tx Device Control TXOFF Monitor MRING DMO Exar Corporation 48720 Kato Road, Fremont CA, 94538 (510) 668-7000 FAX (510) 668-7017 www.exar.com XRT7300 E3/DS3/STS-1 LINE INTERFACE UNIT REV. 1.1.2 ORDERING INFORMATION PART NUMBER PACKAGE TYPE OPERATING TEMPERATURE RANGE XRT7300IV 44 Pin TQFP (10mm x 10mm) -40C to +85C FIGURE 2. PIN OUT OF THE XRT7300 IN THE 44 PIN TQFP 44 43 42 41 40 39 38 37 36 35 34 TxLEV 1 33 RPOS TAOS 2 32 RNEG VDD 3 31 RCLK1 4 30 LCV/(RCLK2) DMO GND 5 29 VDD XRT7300 (Top View) GND 6 28 GND GND 7 27 EXCLK RTIP 8 26 VDD RRING 9 25 GND VDD 10 24 RLOS REGRESET/ 11 23 RLOL RCLK2INV 12 13 14 15 16 17 18 19 20 21 22 2 MTIP REQDIS MRING LOSTHR VDD LLB RLB TTIP TRING STS1/DS3 E3 GND TNDATA HOST/HW TPDATA SDI/(LOSMUTEN) SDO/(LCV) TCLK TXOFF SCLK/(ENCODIS) CS/(DECODIS) ICT