FEATURES
• Monolithic SONET/SDH Transport Overhead Terminating Transceiver for use
   in STS-1, STS-3 (STM-1), or STS-12 (STM-4) line interface applications.
• Operates in one of four modes: STS-1 bit serial mode, STS-1 byte serial
   mode, STS-3/STM-1 byte serial mode, or STS-12/STM-4 byte serial mode.
• Provides independent control of the transmit and receive operating modes.
• Performs byte interleaved multiplexing of lower rate drop side SONET/SDH
   data streams. STS-3 to STS-1, STM-4 to STM-1 and STS-12 to STS-3
   multiplexing modes are supported.
• Processes byte serial data at 6.48 Mbyte/s, 19.44 Mbyte/s or 77.76 Mbyte/s
   depending on the mode selected.
• Frames to the receive stream by monitoring the status of the upstream
   pattern detector provided by available Serial to Parallel / Parallel to Serial
   front end devices.
• Optionally inserts the framing bytes (A1, A2) and the STS identification bytes
   (C1) into the transmit stream.
• Optionally descrambles the receive STS-1, STS-3/STM-1 or STS-12/STM-4
   stream. Optionally scrambles the transmit STS-1, STS-3/STM-1 or
   STS-12/STM-4 stream.
• Calculates and compares the bit interleaved parity error detection codes (B1,
   B2) for the receive stream. Calculates and inserts B1 and B2 in the transmit
   stream.
• Optionally inserts line far end block errors (FEBE) into the Z2 growth byte
   based on received B2 errors.
• Accumulates near end errors (B1, B2) and far end errors (Z2) for
   performance monitoring purposes.
• Extracts the order wire channels (E1, E2) of the receive stream and serializes
   them at 64 kbit/s. Optionally inserts the order wire channels into the transmit
   stream.
• Extracts the data communication channels (D1-D3, D4-D12) and serializes
   them at 192 kbit/s (D1-D3) and 576 kbit/s (D4-D12). Optionally inserts the
   data communication channels into the transmit stream.
• Extracts the section user channel (F1) and serializes it at 64 kbit/s. Optionally
   inserts the section user channel into the transmit stream.
• Extracts the automatic protection switch (APS) channel (K1, K2) and
   serializes it at 128 kbit/s. Detects loss of signal (LOS), out of frame (OOF),
   loss of frame (LOF), far end receive failure (FERF), line alarm indication
   signal (AIS), and protection switching byte failure alarms.
• Inserts FERF and AIS in the transmit stream.
• Provides loss of signal insertion, framing pattern error insertion, and coding
   violation insertion (B1 and B2) for diagnostic purposes. Provides a transmit
   and receive ring control port, allowing alarm and maintenance signal control
   and status to be passed between mate STTXs for applications in ring-based
   add drop multiplexers.
• Low power +5 Volt 0.8 micron CMOS with TTL/CMOS compatible inputs and
   outputs.
• 208 pin copper slugged PQFP package.

APPLICATIONS
• OC-N to OC-M multiplexers
• SONET/SDH add drop multiplexers
• SONET/SDH terminal multiplexers
• Broadband ISDN user network interfaces
• ATM Transmission systems
• SONET/SDH test equipment