XRT72L13 Datasheet, PDF (354/370 Pages) Exar Corporation – M13 MULTIPLEXER/CLEAR CHANNEL DS3 FRAMER IC

XRT72L13
M13 MULTIPLEXER/CLEAR CHANNEL DS3 FRAMER IC
REV. P1.0.6
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PRELIMINARY
This “two-step” De-Multiplexing Process is illustrated
below in Figure 117.
FIGURE 117. SIMPLE ILLUSTRATION OF THE OVERALL SCHEME TO DEMUX A DS3 SIGNAL INTO 28 DS1 SIGNALS
DS1 Channel 1
DS1 Channel 28
M12
DEMUX
DS2 Channel 1
DS2 Channel 2
DS2 Channel 3
DS2 Channel 4
DS2 Channel 5
DS2 Channel 6
DS2 Channel 7
M23
DEMUX
DS3 Channel
5.1.2 .ITU-T G.747 Applications
A very simple, general overview of both the “Multi-
plexing” and “Demultiplexing” schemes that are typi-
cally applied to E1 and DS3 signals (in “ITU-T G.747”
applications) are briefly described below.
In the Transmit Direction:
1. The XRT72L13 will accept 21 E1 signals, via
seven (7) M12 MUX blocks. These M12 MUX
blocks will multiplex these 21 E1 signals into
seven “ITU-T G.747” signals.
2. These seven “ITU-T G.747” signals will then be
routed to the M23 MUX block. The M23 MUX
block will multiplex these seven “ITU-T G.747”
signals into a DS3 data stream.
This “two-step” Multiplexing Process is illustrated be-
low in Figure 118.
FIGURE 118. SIMPLE ILLUSTRATION OF THE OVERALL SCHEME TO MUX 21 E1 SIGNALS INTO A DS3 SIGNAL
E1 Channel 1
E1 Channel 2
E1 Channel 3
G.747
MUX
G.747 Channel 1
G.747 Channel 2
G.747 Channel 3
G.747 Channel 4
G.747 Channel 5
G.747 Channel 6
G.747 Channel 7
M23
MUX
DS3 Channel
In the Receive Direction:
1. The M23 DEMUX block (within the XRT72L13)
will receive a DS3 data stream and will de-multi-
plex it into seven “ITU-T G.747” signals. Each of
these seven “ITU-T G.747” signals will then be
routed to one of the 7 M12 DEMUX blocks.
2. Each of these M12 DEMUX blocks will de-multi-
plex these “ITU-T G.747” signals into 3 E1 sig-
nals. Hence, a total of 21 E1 signals will be multi-
plexed (from the DS3 signal) and will be output
via the XRT72L13.
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