DS21348

Manufacturer Part NumberDS21348
Description3.3V E1/T1/J1 Line Interface
ManufacturerDallas Semiconducotr
DS21348 datasheet
 


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
Page 41
42
Page 42
43
Page 43
44
Page 44
45
Page 45
46
Page 46
47
Page 47
48
Page 48
49
Page 49
50
Page 50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
Page 49/73

Download datasheet (552Kb)Embed
PrevNext
BASIC INTERFACE Figure 9-1
Transmit
Line
N:1
(larger winding
toward the network)
Receive
Line
1:1
Rr
0.1µF
NOTES:
1) All resistor values are ±1%.
2) In E1 applications, the Rt resistors are used to increase the transmitter return loss (Table 9-1). No
return loss is required for T1 applications.
3) The Rr resistors should be set to 60W each if the internal receive-side termination feature is enabled.
When this feature is disabled, Rr = 37.5W for 75W or 60W for 120W E1 systems, or 50W for 100W
T1 lines.
4) See Table 9-1 and Table 9-2 for the appropriate transmit transformer turns ratio (N).
DS21348
Rt
TTIP
VDD (21)
1.0µF
VSS (22)
(non-
polarized)
TRING
Rt
VDD (36)
VSS (35)
RTIP
RRING
Rr
49 of 73
+VDD
0.1µF
10µF
0.01µF
0.1µF
10µF
MCLK
2.048MHz
(this clock can also
be 1.544MHz for T1
only applications)