GENERAL DESCRIPTION
The DS21Q50 E1 quad transceiver contains all the necessary functions for connecting to four E1 lines. The on-board clock/data recovery circuitry coverts the AMI/HDB3 E1 waveforms to an NRZ serial stream. The DS21Q50 automatically adjusts to E1 22AWG (0.6mm) twisted-pair cables from 0km to over 2km in length. The device can generate the necessary G.703 waveshapes for both 75Ω coax and 120Ω twisted-pair cables.

FEATURES
■ Four Complete E1 (CEPT) PCM-30/ISDN-PRI Transceivers
■ Long-Haul and Short-Haul Line Interfaces
■ 32-Bit or 128-Bit Crystal-Less Jitter Attenuator
■ Frames to FAS, CAS, CCS, and CRC4 Formats
■ 4MHz/8MHz/16MHz Clock Synthesizer
■ Flexible System Clock with Automatic Source Switching on Loss-of-Clock Source
■ Two-Frame Elastic-Store Slip Buffer on the Receive Side
■ Interleaving PCM Bus Operation Up to 16.384MHz
■ Configurable Parallel and Serial Port Operation
■ Detects and Generates Remote and AIS Alarms
■ Fully Independent Transmit and Receive Functionality
■ Four Separate Loopback Functions
■ PRBS Generation/Detection/Error Counting
■ 3.3V Low-Power CMOS
■ Large Counters for Bipolar and Code Violations, CRC4 Codeword Errors, FAS Word Errors, and E Bits
■ Eight Additional User-Configurable Output Pins
■ 100-Pin, 14mm x 14mmLQFP Package

APPLICATIONS
    DSLAMs
    Routers
    IMA and WAN Equipment