XRT82D20 SINGLE CHANNEL E1 LINE INTERFACE UNIT AUGUST 2006 REV. 1.0.8 GENERAL DESCRIPTION Clock Recovery and Selectable Crystal-less Jitter attenuator The XRT82D20 is a fully integrated, single channel, Compliant with ETS300166 Return Loss Line Interface Unit (Transceiver) for 75 or 120 E1 (2.048 Mbps) applications. The LIU consists of a Compliant with the ITU-T G.823 Jitter Tolerance receiver with adaptive data slicer for accurate data Requirements and clock recovery and a transmitter which accepts Remote, Local and Digital Loop backs either single or dual-rail digital inputs for signal transmission to the line using a low- impedance Declares and Clears LOS per ITU-T G.775 differential line driver. The LIU also includes a crystal- Logic Inputs accept either 3.3V or 5.0V levels less jitter attenuator for clock and data smoothing which, depending on system requirements, can be 0 0 - 40 C to 85 C Temperature Range selected in either the transmit or receive path. Low Power Dissipation 145mW with 120 or Coupling the XRT82D20 to the line requires 160mW with 75 typical transformers on both the Receiver and Transmitter +3.3V or +5V Supply Operation sides, and supports both 120 balanced and 75 unbalanced interfaces. The receiver can be Pin Compatible with the XRT7288 capacitive coupled to for cost reduction APPLICATIONS FEATURES PDH Multiplexers Complete E1 (CEPT) line interface unit SDH Multiplexers Generates transmit output pulses that are Digital Cross-Connect Systems compliant with the ITU-T G.703 Pulse Template for 2.048Mbps (E1) rates DECT (Digital European Cordless Telephone) Base On-Chip Pulse Shaping for both 75 and 120 Stations Line Drivers CSU/DSU Equipment Test Equipment FIGURE 1. BLOCK DIAGRAM OF THE XRT82D20 TTIP TClk HDB3 Tx Pulse Line TPOS MUX Encoder Shaper Driver TNEG TRing Jitter Attenuator Local Loopback Digital Remote Loopback Loopback LOS RLOS Detect Data & Timing RClk Recovery HDB3 Data Peak RTIP RPOS MUX Decoder Slicer Detector RRing RNEG Timing MClk Generator Exar Corporation 48720 Kato Road, Fremont CA, 94538 (510) 668-7000 FAX (510) 668-7017 www.exar.com XRT82D20 SINGLE CHANNEL E1 LINE INTERFACE UNIT REV. 1.0.8 FIGURE 2. PINOUT OF THE XRT82D20 1 28 RTIP RLOS 2 27 RRing ClkLOS 3 26 MuteRx TNEG/CODE 4 25 AGND RNEG/LCV 5 24 AVDD RClk 6 23 TxLEV RPOS/RData 7 22 TTIP TClk 8 21 TVDD TPOS/TData 9 20 TRing LLoop TGND RLoop 10 19 JAEN DLoop 11 18 DIGI ATM 12 17 RAOS JATx/Rx 13 16 MClk TAOS 14 15 ORDERING INFORMATION PART PACKAGE OPERATING TEMPERATURE RANGE o o XRT82D20IW 28 Lead 300 Mil Jedec SOJ -40 C to + 85 C 2