Nortel Networks 553-3001-211 manual Functional description, OPS analog line card block diagram

Page 158 of 894 NT1R20 Off-Premise Station Analog Line card

Functional description

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.

Figure 22

OPS analog line card – block diagram

Line interface units 0–3

Input/output		Codec
interface
control	PCM

Front	Address/
panel
	data bus
LED
	Micro-
	controller

Analog XFMR

hybrid

Signaling relays

(ringing, battery

reversal)

Loop current/

dialpulse detect

Tip Analog

Ring telephone lines

Line interface units 4–7

Card slot
address
Backplane
	Codec
Card LAN	PCM
interface

Async card

LAN link

	Tx PCM
Controller	Rx PCM
		DS-30X
card	5.12 MHz
		interface		Line
	clock
			Signaling	signaling
	1 kHz
			and status interface
	frame sync

Analog XFMR

hybrid

Signaling relays

(ringing, battery

reversal)

Loop current/

dialpulse detect

Line interface unit power

Tip Analog

Ring telephone lines

Control

logic

+5 V dc			Rin	g	ing
analog
hybrid	– 48	V dc			Rsync
±15 V dc
analog	battery
power

Power	+8.5 V dc	Reg	+5 V dc logic power
supplies			553-6193

553-3001-211 Standard 2.00 September 2004