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XRT83SL28
REV. 1.0.0
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
2.8
Line Termination (TTIP/TRING)
The output stage of the transmit path generates standard bipolar signals to the line for both E1 (75 Ohm)
coaxial cable and E1 (120 Ohm) twisted pair. The XRT83L28 has built-in output impedance matching for both
75 Ohm and 120 Ohm operations. This eliminates the need to change any external components while
switching from 75 Ohm to 120 Ohm operation. The transmitter interface only requires one 0.68µF DC blocking
capacitor with a 1:2 transformer as shown in Figure 17.
FIGURE 17. TYPICAL CONNECTION DIAGRAM USING INTERNAL TERMINATION
XRT83SL28 LIU
TTIP
1:2
C=0.68uF
Transmitter
Output
Line Interface E1
TRING
One Bill of Materials
Internal Impedance
23
EXAR [ EXAR CORPORATION ]
