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Table of Contents
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October 7, 2003
Table of Contents
FEATURES ........................................................................................................................................................................ 1
APPLICATIONS ................................................................................................................................................................ 1
BLOCK DIAGRAM ............................................................................................................................................................ 2
1 PIN ASSIGNMENT ............................................................................................................................................................ 3
2 PIN DESCRIPTION ........................................................................................................................................................... 4
3 FUNCTIONAL DESCRIPTION ........................................................................................................................................ 10
3.1
T1 / E1 / J1 MODE SELECTION .................................................................................................................................................................. 12
3.2
RECEIVER IMPEDANCE MATCHING ......................................................................................................................................................... 13
3.3
ADAPTIVE EQUALIZER .............................................................................................................................................................................. 15
3.4
DATA SLICER .............................................................................................................................................................................................. 15
3.5
CLOCK AND DATA RECOVERY ................................................................................................................................................................ 15
3.6
RECEIVE JITTER ATTENUATOR ............................................................................................................................................................... 16
3.7
DECODER .................................................................................................................................................................................................... 17
3.7.1
Line Code Rule ............................................................................................................................................................................... 17
3.7.1.1
T1 / J1 Mode .................................................................................................................................................................... 17
3.7.1.2
E1 Mode ........................................................................................................................................................................... 17
3.7.2
Decode Error Detection ................................................................................................................................................................. 17
3.7.2.1
T1 / J1 Mode .................................................................................................................................................................... 17
3.7.2.2
E1 Mode ........................................................................................................................................................................... 17
3.7.3
LOS Detection ................................................................................................................................................................................ 18
3.8
FRAME PROCESSOR ................................................................................................................................................................................. 21
3.8.1
T1/J1 Mode ...................................................................................................................................................................................... 21
3.8.1.1
Synchronization Searching ............................................................................................................................................... 21
3.8.1.1.1
Super Frame (SF) Format ............................................................................................................................. 21
3.8.1.1.2
Extended Super Frame (ESF) Format ........................................................................................................... 22
3.8.1.1.3
T1 Digital Multiplexer (DM) Format (T1 only) ................................................................................................ 23
3.8.1.1.4
Switch Line Carrier - 96 (SLC-96) Format (T1 only) ...................................................................................... 24
3.8.1.2
Error Event And Out Of Synchronization Detection .......................................................................................................... 25
3.8.1.2.1
Super Frame (SF) Format ............................................................................................................................. 25
3.8.1.2.2
Extended Super Frame (ESF) Format ........................................................................................................... 25
3.8.1.2.3
T1 Digital Multiplexer (DM) Format (T1 only) ................................................................................................ 25
3.8.1.2.4
Switch Line Carrier - 96 (SLC-96) Format (T1 only) ...................................................................................... 25
3.8.1.3
Overhead Extraction (T1 Mode SLC-96 Format Only) ..................................................................................................... 26
3.8.1.4
Interrupt Summary ............................................................................................................................................................ 26
3.8.2
E1 Mode .......................................................................................................................................................................................... 28
3.8.2.1
Synchronization Searching ............................................................................................................................................... 30
3.8.2.1.1
Basic Frame .................................................................................................................................................. 30
3.8.2.1.2
CRC Multi-Frame ........................................................................................................................................... 31
3.8.2.1.3
CAS Signaling Multi-Frame ........................................................................................................................... 32
3.8.2.2
Error Event And Out Of Synchronization Detection .......................................................................................................... 32
3.8.2.2.1
Out Of Basic Frame Synchronization ............................................................................................................ 33
3.8.2.2.2
Out Of CRC Multi-Frame Synchronization .................................................................................................... 33
3.8.2.2.3
Out Of CAS Signaling Multi-Frame Synchronization ..................................................................................... 33
3.8.2.3
Overhead Extraction ......................................................................................................................................................... 33
3.8.2.3.1
International Bit Extraction ............................................................................................................................. 33
3.8.2.3.2
Remote Alarm Indication Bit Extraction ......................................................................................................... 33