xr
PRELIMINARY
XRT86VL38
REV. P1.0.6
OCTAL T1/E1/J1 FRAMER/LIU COMBO
350
7.4
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
µ
F. 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 60.
F
IGURE
60. T
YPICAL
C
ONNECTION
D
IAGRAM
U
SING
I
NTERNAL
T
ERMINATION
T
TIP
T
RING
XRT86VL38 LIU
1:2
Internal Impedance
Line Interface T1/E1/J1
C=0.68uF
One Bill of Materials
Transmitter
Output