Functional Description - Nortel Circuit Card Installation Manual

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Functional description

Figure 22
OPS analog line card – block diagram
Input/output
Front
panel
LED
Card slot
address
Backplane
Async card
LAN link
Tx PCM
Rx PCM
Controller
card
5.12 MHz
clock
1 kHz
frame sync
+8.5 V dc
Power
supplies
553-3001-211 Standard 3.00
NT1R20 Off-Premise Station Analog Line card
This functional description of the NT1R20 Off-Premise Station (OPS) analog
line card is divided into two parts. First, a description of the card's control,
signaling, and power interfaces is given, followed by a description of how the
card itself functions. See Figure 22.
interface
control PCM
Address/
data bus
Micro-
controller
Card LAN
PCM
interface
DS-30X
interface
Signaling
and status
Control
logic
Reg + 5 V dc logic power
August 2005
Line interface units 0–3
Codec
Line interface units 4–7
Codec
Line interface unit power
Line
signaling
interface
+ 5 V dc
analog
hybrid
±15 V dc
analog
power
Analog
XFMR
hybrid
Signaling relays
Tip
(ringing, battery
Ring
reversal)
Loop current/
dialpulse detect
Analog
XFMR
hybrid
Signaling relays
Tip
(ringing, battery
Ring
reversal)
Loop current/
dialpulse detect
Ringing
– 48 V dc Rsync
battery
Analog
telephone
lines
Analog
telephone
lines
553-6193