XRT86L30
REV. 1.0.1
SINGLE T1/E1/J1 FRAMER/LIU COMBO
8.4
Line Termination (TTIP/TRING)
The output stage of the transmit path generates standard return-to-zero (RZ) signals to the line interface for T1/
E1/J1 twisted pair or E1 coaxial cable. The physical interface is optimized by placing the terminating
impedance inside the LIU. This allows one bill of materials for all modes of operation reducing the number of
external components necessary in system design. The transmitter outputs only require one DC blocking
capacitor of 0.68
µF. For redundancy applications (or simply to tri-state the transmitters), set TxTSEL to a "1" in
the appropriate channel register. A typical transmit interface is shown in Figure 56.
F
IGURE 56. TYPICAL
C
ONNECTION
D
IAGRAM
U
SING
INTERNAL TERMINATION
XRT86L30 LIU
TTIP
1:2
C=0.68uF
Transmitter
Output
Line Interface T1/E1/J1
TRING
One Bill of Materials
Internal Impedance
188
EXAR [ EXAR CORPORATION ]
