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NT8D02 Digital Line Card
553-3001-105
Standard 5.00
June 1999
Figure 57
Digital line card—block diagram
Digital
line
interface
Micro-
controller
5.12 MHz clock
Tx PCM
DS-30X loop
Card
LAN link
Power
supplies
Front
panel
LED
Card LAN
interface
Tip
TCM
loop
interface
circuit
Digital
phone lines
Line interface units 0–7
Line interface units 8–15
Ring
Tip
TCM
loop
interface
circuit
Digital
phone lines
Ring
Rx PCM
1 kHz frame sync
Card slot
address
Sanity
timer
553-6163
Digital
line
interface
+ 5 V dc
+10 V dc
±15 V dc
Reg
+15
+10
+10 V dc
Address/
data bus
Summary of Contents for NT1R20
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Page 4: ...iv 553 3001 105 Standard 5 00 June 1999 iv ...
Page 12: ...xii Contents 553 3001 105 Standard 5 00 June 1999 ...
Page 76: ...Page 52 of 290 Description 553 3001 105 Standard 5 00 June 1999 ...
Page 154: ...Page 130 of 290 NT5D11 Line side T1 Interface Card 553 3001 105 Standard 5 00 June 1999 ...
Page 276: ...Page 252 of 290 QPC452 Basic 500 2500 Analog Line Card 553 3001 105 Standard 5 00 June 1999 ...
Page 306: ...Page 282 of 290 List of terms 553 3001 105 Standard 5 00 June 1999 ...
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