Nortel Enterprise 1000 Reference Manual page 102

Page 102 of 236
Figure 35
E&M trunk card — block diagram
Input/output
Front
panel
LED
controller
Card slot
address
Back-
plane
Card LAN
interface
Async card
LAN link
Tx PCM
Rx PCM
Con-
troller
card
5.12 MHz
clock
1 kHz
frame sync
+8.5 V dc
Power
supplies
553-3023-211 Standard 1.00 June 2001
NT8D15 E&M Trunk Card
interface
control
Address/
data bus
PCM
Micro-
DS-30X
interface
Signaling
and status
Control
logic
+5 V dc logic power
Reg
Trunk interface units 0–3
Codec
Line interface unit power
Trunk
signaling
interface
+5 V dc
analog
hybrid
±15 V dc
analog
power
Tip/ring
Analog
(2/4 wire)
XFMR
hybrid
Voice
band
Signaling relays
(ringing, battery
reversal)
E&M
Sup.
Loop current/
signaling
dialpulse detect
Ringing
Ð 48 V dc Rsync
battery
Facility
services
interfaces
(2-W E&M,
4-W E&M,
and Paging)
Signaling
interface
553-CSE6201