DS21348 Dallas Semiconducotr, DS21348 Datasheet - Page 48

• Manufacturer Part Number: DS21348
• Description: 3.3V E1/T1/J1 Line Interface
• Manufacturer: Dallas Semiconducotr

9.4
The DS21348 is capable of receiving a 2.048MHz square-wave synchronization clock as specified in
section 10 of ITU G.703. In order to use the DS21348 in this mode, set the Receive Synchronization
Clock Enable (CCR5.3) = 1. The DS21348 can also transmit the 2.048MHz square-wave synchronization
clock as specified in section 10 of G.703. In order to transmit the 2.048 MHz clock, set the Transmit
Synchronization Clock Enable (CCR5.2) = 1.
LINE BUILD OUT SELECT FOR E1 IN REGISTER CCR4 (ETS = 0) Table 9-1
Note: See Figure 9-1, Figure 9-2, and Figure 9-3.
LINE BUILD OUT SELECT FOR T1 IN REGISTER CCR4 (ETS = 1) Table 9-2
Note: See Figure 9-1, Figure 9-2, and Figure 9-3.
TRANSFORMER SPECIFICATIONS FOR 3.3V OPERATION Table 9-3
Turns Ratio 3.3V Applications
Primary Inductance
Leakage Inductance
Intertwining Capacitance
Transmit Transformer DC Resistance
Receive Transformer DC Resistance
L2
0
0
1
1
L2
0
0
0
0
1
1
1
1
G.703 Synchronization Signal
Primary (Device Side)
Secondary
Primary (Device Side)
Secondary
L1
0
0
0
0
L1
0
0
1
1
0
0
1
1
SPECIFICATION
L0
0
1
0
1
L0
0
1
0
1
0
1
0
1
3.3V
3.3V
3.3V
3.3V
V
3.3V
3.3V
3.3V
3.3V
3.3V
3.3V
3.3V
3.3V
DD
V
DD
75W normal
120W normal
75W w/ high return loss
120W w/ high return loss
DSX-1 (0 to 133 feet) /
DSX-1 (133 to 266 feet)
DSX-1 (266 to 399 feet)
DSX-1 (399 to 533 feet)
DSX-1 (533 to 655 feet)
-7.5dB CSU
-15dB CSU
-22.5dB CSU
APPLICATION
APPLICATION
0 DB CSU
1:1 (receive) and 1:2 (transmit) ±2%
600mH minimum
1.0mH maximum
40pF maximum
1.0W maximum
2.0W maximum
1.2W maximum
1.2W maximum
48 of 73
RECOMMENDED VALUE
1:2
1:2
1:2
1:2
1:2
1:2
1:2
1:2
1:2
1:2
1:2
1:2
N
N
RETURN LOSS
RETURN LOSS
21dB
21dB
NM
NM
NM
NM
NM
NM
NM
NM
NM
NM
11.6W
6.2W
0W
0W
0W
0W
0W
0W
0W
0W
0W
0W
Rt
Rt