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DS3171/DS3172/DS3173/DS3174
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3 FEATURE DETAILS
The following sections describe the features provided by the DS3171 (single), DS3172 (dual), DS3173 (triple), and
DS3174 (quad) single-chip transceivers (framers and LIUs, SCTs).
3.1 Global
Features
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Supports the following transmission protocols:
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C-bit DS3
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M23 DS3
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G.751 E3
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G.832 E3
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Clear-channel serial data at line rates up to 52 Mbits/s
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Optional transmit loop timed clock(s) mode using the associated port’s receive clock(s)
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Optional transmit clock mode using references generated by the internal Clock Rate Adapter (CLAD)
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Requires only a single reference clock for all three LIU data rates using internal CLAD
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The LIU can be powered down and bypassed for direct logic IO to/from line circuits.
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Jitter attenuator can be placed in either transmit or receive path when the LIU is enabled.
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Clock, data and control signals can be inverted for a direct interface to many other devices
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Detection of loss of transmit clock and loss of receive clock
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Automatic one-second, external or manual update of performance monitoring counters
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Each port can be placed into a low-power standby mode when not being used
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Framing and line code error insertion available
3.2 Receive DS3/E3 LIU Features
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AGC/Equalizer block handles from 0 dB to 15 dB of cable loss
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Loss-of-lock PLL status indication
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Interfaces directly to a DSX monitor signal (20 dB flat loss) using built-in pre-amp
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Digital and analog Loss of Signal (LOS) detectors (ANSI T1.231 and ITU G.775)
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Per-channel power-down control
3.3 Receive DS3/E3 Framer Features
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Frame synchronization for M23 or C-bit Parity DS3, or G.751 E3 or G.832 E3
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B3ZS/HDB3/AMI decoding
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Detection and accumulation of bipolar violations (BPV), code violations (CV), excessive zeros occurrences
(EXZ), F-bit errors, M-bit errors, FAS errors, LOF occurrences, P-bit parity errors, CP-bit parity errors, BIP-8
errors, and far end block errors (FEBE)
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Detection of RDI, AIS, DS3 idle signal, loss of signal (LOS), severely errored framing event (SEFE), change of
frame alignment (COFA), receipt of B3ZS/HDB3 codewords, DS3 application ID bit, DS3 M23/C-bit format
mismatch, G.751 national bit, and G.832 RDI (FERF), payload type, and timing marker bits
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HDLC port for DS3 path maintenance data link (PMDL), G.751 national bit or G.832 NR or GC channels
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FEAC port for DS3 FEAC channel
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16-byte Trail Trace Buffer port for G.832 trail access point identifier
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DS3 M23 C bits and stuff bits configurable as payload or overhead, stored in registers for software inspection
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Most framing overhead fields presented on the receive overhead port
3.4 Transmit DS3/E3 Formatter Features
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Insertion of framing overhead for M23 or C-bit parity DS3, or G.751 E3 or G.832 E3
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B3ZS/HDB3 encoding
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Generation of RDI, AIS, and DS3 idle signal
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Automatic or manual insertion of bipolar violations (BPVs), excessive zeros (EXZ) occurrences, F-bit errors, M-
bit errors, FAS errors, P-bit parity errors, CP-bit parity errors, BIP-8 errors, and far end block errors (FEBE)
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HDLC port for DS3 path maintenance data link (PMDL), G.751 national bit or G.832 NR or GC channels