FEATURES
• Monolithic single-chip device that integrates four full-featured T1 framers and transmitters for terminating duplex DS1 signals.
• Supports SF, ESF, T1DM (DDS), and SLC®96 format DS1 signals.
• Supports unframed mode. Supports B8ZS or AMI line codes.
• Supports transfer of PCM and signalling data to/from 1.544 Mbit/s, 2.048 Mbit/s, 12.352 Mbit/s, or 16.384 Mbit/s backplane buses.
• Supports n x DS0 backplane interface for fractional T1.
• Provides robbed-bit signalling extraction/insertion, programmable idle and digital milliwatt code substitution, and two superframes of signalling debounce on a per-channel basis.
• Provides trunk conditioning which forces programmable trouble code substitution and signalling conditioning on all/selected channels.
• Provides ESF bit-oriented code detection/generation, and an HDLC interface for terminating/generating the ESF data link.
• Software and functionally compatible with the PM4341A T1XC Single T1 Transceiver. Pin-compatible with the PM6344 EQUAD Quad E1 Framer.
• Provides an 8-bit microprocessor bus interface for configuration, control, and status monitoring.
• Low power 5 V CMOS technology.
• Available in a rectangular 128-pin PQFP (14 by 20 mm) package. RECEIVE SECTION
• Recovers clock and data using a digital PLL for high jitter tolerance.
• Accepts/provides dual- or single-rail digital PCM inputs/outputs. Accepts gapped data streams to support higher rate demultiplexing.
• Provides Loss Of Signal (LOS) detection, and red, yellow, and Alarm Indication Signal (AIS) alarm detection.
• Detects violations of the ANSI T1.403 12.5% pulse density rule over a moving 192-bit window.
• Provides programmable in-band loopback code detection.
• Supports line and path performance monitoring according to AT&T and ANSI specifications. Accumulators are provided for counting, ESF CRC-6 errors, Framing bit errors, Line Code Violations (LCVs), and Loss Of Frame (LOF) or change of frame alignment events.
• Extracts the data link in ESF, T1DM (DDS), or SLC®96 modes. Extracts selected channels.
• Provides a 2-frame elastic store buffer for jitter and wander attenuation.

APPLICATIONS
• T1/T3 Multiplexers and Digital Private Branch Exchanges (PBXs)
• T1 Frame Relay Interfaces
• T1 ATM Interfaces
• Fractional T1 Interfaces
• Digital Access and Cross-Connect Systems (DACS) and Electronic DSX Cross-Connect Systems (EDSXs)
• Digital Loop Carriers (DLCs)
• T1 Channel Service Units (CSUs) and Data Service Units (DSUs)
• ISDN Primary Rate Interfaces (PRIs)
• SONET Add/Drop Multiplexers (ADMs)