XRT74L73 Datasheet, PDF (424/488 Pages) Exar Corporation – 3 CHANNEL, ATM UNI/PPP DS3/E3 FRAMING CONTROLLER

XRT74L73
3 CHANNEL, ATM UNI/PPP DS3/E3 FRAMING CONTROLLER
REV. P1.0.1
PRELIMINARY
FIGURE 185. APPROACH TO INTERFACING THE XRT74L73 FRAMER IC TO THE XRT73L00 DS3/E3/STS-1 LIU
TxSER
TxInClk
TxFrame
NIBBLEINTF
RESETB
INTB
CSB
RW
DS
AS
INTB
A[8:0]
D[7:0]
5V
RxSer
RxClk
RxFrame
RxLOS
RxOOF
RxRED
RxAIS
U1
46
43
TxSER
61 ^TxInClk
TxFrame
25
NIBBLEINTF
28
RESETB
13
8 ^INTB
7 ^CSB
10 ^WRB_RW
9 ^RDB_DS
6
ALE_AS
Rdy_Dtck
15
16 ^A0
17 ^A1
18 ^A2
19 ^A3
20 ^A4
21 ^A5
22
23
A6
A7
A8
32
33 ^D0
34
35
D1
D2
36 ^D3
37 ^D4
38 ^D5
39 ^D6
D7
27
MOTO
86
88
RxSer
90 ^RxClk
RxFrame
95
94 ^RxLOS
93 ^RxOOF
87 ^RxRED
RxAIS
XRT74L74
65
TxPOS
64
TxNEG
63
TxLineClk
79
DMO
78
ExtLOS
RLOL ⁷⁷
69
LLOOP
70
RLOOP
68
TAOS
TxLEV ⁶⁷
66
ENCODIS
REQB ⁷¹
76
RxPOS
75
RxNEG
74
RxLineClk
U2
37
TPDATA
38
TNDATA
36
TCLK
4
DMO
24
RLOS
23 _RLOL
14
LLB
15
RLB
2
TAOS
1 _TxLEV
21
ENCODIS
12 _REQDIS
33
RPOS
32
RNEG
31
RCLK1
XRT73L00
41
TTIP
40
TRING
44
MTIP
43
MRING
1 ^R3 2
270
1 ^R4 2
270
R1
1
2
36
1 ^T1 5
R2
1
2
36
4
8
1:1
TTIP
TRING
8
RTIP
9
RRING
C1
12
0.01uF
R5
37.5
R6
37.5
1 ^T2 5
4
8
1:1
RTIP
RRING
The Transmit Section of the XRT74L73 contains a
block which is known as the Transmit E3 LIU Inter-
face block. The purpose of the Transmit E3 LIU Inter-
face block is to take the Outbound E3 data stream,
from the Transmit E3 Framer block, and to do the fol-
lowing:
1. Encode this data into one of the following line
codes
a. Unipolar (e.g., Single-Rail)
b. AMI (Alternate Mark Inversion)
c. HDB3 (High Density Bipolar - 3)
2. And to transmit this data to the LIU IC.
Figure 186 presents a simple illustration of the
Transmit E3 LIU Interface block.
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