Nortel Networks Circuit Card User Manual

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Page 570 of 906
 NT8D14 Universal Trunk card
Functional description
Figure 114 shows a block diagram of the major functions contained on the 
NT8D14 Universal Trunk card. Each of these functions is described on the 
following pages.
Figure 114
NT8D14 Universal trunk card – block diagram
Input/output
interface
control
Codec
PCM
Micro-
controller
DS-30X
interface
5.12 MHz
clock
Tx PCM
Async card
LAN link
Front
panel
LED
Card LAN
interface
Analog
hybrid
XFMR
Tip
Signaling
relays
Analog
trunk facilities
(CO/FX/WATS,
DID, tie, RAN,
or paging)
Trunk interface units 0–3
Signal
detection
Signal
hybrid
Ring
*
*
Analog
hybrid
XFMR
Tip
Signaling
relays
Analog
trunk facilities
(CO/FX/WATS,
DID, tie, RAN,
or paging)
Trunk interface units 4–7
Signal
detection
Signal
hybrid
Ring
*
*
Codec
PCM
Rx PCM
1 kHz
frame sync
Card slot
address
Back-
plane
Con-
troller
card
Trunk
signaling
interface
Control
logic
Signaling
and status
Address/
data bus
*
Signaling 
lines for 
RAN or 
paging 
control
553-CSE6197