DS3 / E3 / STS-1 Transceivers

General Description

The 78P2241B is a line interface transceiver IC for E3, DS3, STS-1, and ATM applications. It includes clock recovery and transmitter pulse shaping functions for applications using 75-ohm coaxial cable at distances up to 1100 feet. These applications include DSLAMs, digital multiplexers, SONET Add/Drop Multiplexers, PDH equipment, DS3 to Fiber optic and microwave modems, and ATM WAN access for routers and switches.
The receiver recovers clock and data from a B3ZS or HDB3 coded AMI signal. It can compensate for over 12dB of cable and 6dB of flat loss. The transmitter generates a signal that meets the standard pulse shape requirements.
The 28-pin PLCC 78P2241B is pin and functionally compatible to the 78P7200L (28 PLCC version), but it adds a B3ZS/HDB3 ENDEC, line code violation detector, loop-back and clock polarity selection as well as ability to receive a DSX3 monitor signal.

The 78P2241B is manufactured in an advanced BICMOS process and operates from a single 5V or 3.3 V power supply voltage. It consumes less than 110 mA of supply current.


  • Single chip transmit and receive interface for E3, DS3 and STS-1 applications.
  • Interface to 75 ohm coaxial cable over 1100 feet at speeds up to 51.84 Mbps.
  • Compliant with ANSI T1.102-1993, Telcordia GR-499-CORE and GR-253-CORE, ITU-T G.703,G.823 for jitter tolerance, and G.775 for loss of signal.Compliant with ATM FORUM af-phy-0034 (E3 public UNI) and af-phy-0054 (DS3 public UNI).
  • Easily Interfaced to ATM framer ICs such as PMC 7345 , 7346 QJET and 7321.
  • Unique clock recovery requires no reference clock or crystal oscillator.
  • Receive DS3-high and DSX3 monitor signals
  • Includes diagnostic loop-back for AMI and digital signals.
  • Includes a selectable B3ZS/HDB3 ENDEC.
  • Pin compatible to 78P7200 (28-lead PLCC) and 78P2241.
  • 28-lead PLCC and 48-lead TQFP packages
  • 3.3 or 5 V operation, ICC<110mA
  • Input circuit works either Transformer or Capacitor coupled

    Line-code violation detector