PM4341AT1XC
DATA SHEET
PMC-900602
ISSUE 7
T1 FRAMER/TRANSCEIVER
5
DESCRIPTION
The PM4341A Single T1 Framer/Transceiver (T1XC) is a feature-rich device
suitable for use in many T1 systems with a minimum of external circuitry. The
T1XC is software configurable, allowing feature selection without changes to
external wiring.
On the receive side, the T1XC recovers clock and data and can be configured to
frame to any of the common DS-1 signal formats: SF, ESF, T1DM (DDS), or
SLC®96. Analog circuitry is provided to allow direct reception of a DSX-1
compatible signal up to 655 feet from the cross-connect by using only an external
transformer and passive components.The T1XC also supports detection of
various alarm conditions such as loss of signal, pulse density violation, red
alarm, yellow alarm, and AIS alarm. The T1XC detects and indicates the
presence of yellow and AIS patterns and also integrates yellow, red, and AIS
alarms as per industry specifications.
Performance monitoring with accumulation of CRC-6 errors, framing bit errors,
line code violations, and loss of frame events is provided. The T1XC also detects
the presence of in-band loopback codes, ESF bit oriented codes, and detects
and terminates HDLC messages on the ESF data link. An elastic store for slip
buffering and adaptation to backplane timing is provided, as is a signalling
extractor that supports signalling debounce, signalling freezing, idle code
substitution, digital milliwatt tone substitution, data inversion, and signalling bit
fixing on a per-channel basis. Receive side data and signalling trunk
conditioning is also provided.
On the transmit side, the T1XC generates framing for SF, ESF, T1DM (DDS), and
SLC®96 DS1 formats, or framing can be optionally disabled. Internal analog
circuitry allows direct transmission of a DSX-1 compatible signal using only an
external transformer. Digitally programmable line build out allows transmission of
DSX-1 compatible signals up to 655 feet from the cross-connect. The T1XC also
supports signalling insertion, idle code substitution, digital milliwatt tone
substitution, data inversion, and zero code suppression on a per-channel basis.
The zero code suppression is selectable to Bell (bit 7), GTE, or DDS standards,
and can also be disabled. Transmit side data and signalling trunk conditioning is
provided.
The T1XC can also generate in-band loopback codes, ESF bit oriented codes,
and transmit HDLC messages on the ESF data link. The T1XC can generate a
low jitter transmit clock and provides a FIFO for transmit jitter attenuation. When
not used for jitter attenuation, the full or empty status of this FIFO is made
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
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PMC [ PMC-SIERRA, INC ]
