5V T1/J1 Line Interface Unit

Complete 5V, T1 Line Interface Unit (LIU) for Short-Haul and Long-Haul Applications

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The DS2149 is a complete T1 line interface unit (LIU) for short-haul and long-haul applications. Receive sensitivity adjusts automatically to the incoming signal and can be limited to -18dB, -26dB, or -36dB. The device can generate the necessary DSX-1 line build-outs or CSU line build-outs of 0dB, -7.5dB, -15dB, and -22.5dB. The on-board crystal-less jitter attenuator requires a 1.544MHz reference clock. The jitter attenuator FIFO is selectable to either 32 bits or 128 bits in depth and can be placed in either the transmit or receive data paths. The DS2149 has diagnostic capabilities such as loopbacks and QRSS pattern generation and detection. The device can also generate and detect the in-band loop-up and loop-down codes specified in AT&T 62411. The device can be configured for control using a serial interface, or for hardware mode. The device fully meets all of the latest T1 specifications including ANSI T1.102-1999, ANSI T1.403-1999, ANSI T1.408, and AT&T 62411.
DS2149: Block Diagram DS2149: Block Diagram Enlarge+

Key Features

  • Fully integrated line interface unit (LIU)
  • Pin compatible with LXT362
  • Supports both long haul and short haul
  • Crystal-less jitter attenuator
  • Jitter attenuator programmable for transmit or receive path
  • Meets ANSI T1.102, T1.403, T1.408, AT&T 62411
  • Usable receive sensitivity of 0dB to -36dB, which allows the device to operate on 0.63mm (22AWG) cables up to 6k feet in length
  • Five line build-out settings for short-haul applications
  • Four CSU filters from 0dB to -22.5dB
  • Transmit/receive performance monitors with driver-fail, monitor-open and loss-of-signal outputs
  • Bipolar or NRZ interface
  • Programmable B8ZS encoder/decoder
  • QRSS generator/detector
  • Local, remote, and analog loopbacks
  • Generates and detects in-band loop-up and loop-down codes
  • Serial interface provides access to control registers
  • Applications/Uses

    • Channel Banks
    • Channel Service Units (CSUs)
    • Data Service Units (DSUs)
    • Muxes
    • Routers/Switches
    • Routers/Switches
    • T1/E1 Test Equipment
    Product Reliability Reports: DS2149.pdf 
    Device   Fab Process   Technology   Sample size   Rejects   FIT at 25°C   FIT at 55°C   Material Composition  

    Note : The failure rates are summarized by technology and mapped to the associated material part numbers. The failure rates are highly dependent on the number of units tested.

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