XRT72L13 Datasheet, PDF (1/370 Pages) Exar Corporation – M13 MULTIPLEXER/CLEAR CHANNEL DS3 FRAMER IC

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PRELIMINARY
XRT72L13
APRIL 2001
M13 MULTIPLEXER/CLEAR CHANNEL DS3 FRAMER IC
REV. P1.0.6
GENERAL DESCRIPTION
The XRT72L13 is a fully integrated, low power, Multi-
plexer/Framer IC which performs Multiplexing/De-
mutiplexing of 28 DS1or 21 E1 signals into/from a
DS3 signal with either M13 or C-bit parity frame for-
mat, performs Clear Channel DS3 Framing, and sup-
ports High speed HDLC/LAPD data linking.
The XRT72L13 also contains M12 and M23 bit-inter-
leaving multiplexing/demultiplexing functions with
necessary stuffing and destuffing control. Seven in-
ternal DS2/G.747 framers are included to support
Mux/Demux purposes.
The XRT72L13 contains an integral DS3 Framer
which provides Clear Channel DS3 Framing and Er-
ror Accumulation in accordance with ANSI/ITU-T
specifications.
The XRT72L13 provides the intelligent functions of
DS3/DS2 mode control, signaling control, error and
alarm reporting and handles the HDLC/LAPD data
link through internal registers accessible via an 8-bit
parallel, memory mapped, µProcessor interface.
FEATURES
• A fully integrated device that supports:
Multiplexing/Demultiplexing Mode
Clear Channel DS3 Framer Mode
High Speed HDLC Controller Mode
• Supports Multiple Loop-back modes
• Smooths gapped clock signals
• Supports Intel or Motorola PIO µP interfaces
• Available in a 208 pin PQFP package
• Single 3.3V Power Supply
• 5V Tolerant I/O
• Operates over the Industrial Temperature Range
APPLICATIONS
• M13 Multiplexer/Demuliplexer Applications.
• Frame Relay Systems
• Digital Access and Cross Connect Systems
• Local Digital Switch
• Add/Drop Multiplexers
• DS3 Data/Channel Service Units.
• Test Equipment
FIGURE 1. BLOCK DIAGRAM OF THE XRT72L13 MULTIPLEXER/FRAMER
TxHDLC
ConTxtrHoDlleLrC
Controller
TxHDLC[0:7]
TxHDLCClk
Send_FCS
TxPOS
TxNEG
TxLine Clk
RxPOS
RxNEG
RxLine Clk
Clear Channel
DCSle3aFr rCamhaenr ^nel
DS3 Framer
32/64 Bit
De-Jitter
FIFO
M23
MUMX23
MUX
M12
MUMX12
MUX
DS2 or G.747
Data Streams
M23
DEMMU2X3
DEMUX
M12
DEMUX
TxDS1[0:27]
TxClk[0:27]
RxDS1[0:27]
RxClk[0:27]
Microprocessor
MIinctreorpfarocceessor
Interface
RxHDLC
CoRntxrHoDlleLrC
Controller
RxHdlc[0:7]
RxHDLCClk
RxIdle
Valid-FCS
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • [phone] • FAX [phone] • www.exar.com