Intel Evaluation Board for Octal E1 Applications LXD381 User Manual

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Evaluation Board for Octal E1 Applications — LXD381
 Developer Manual
9
2.9
Line Interface Connection
Access to the line interface is provided through the green and white banana jacks. The TIP signal is 
routed to the white jacks for both transmit and receive directions. The RING signal is routed to the 
green jacks for both directions.
2.10
Line Interface Circuit
Two octal transformers are used for channels 0 to 3 and 4 to 7. Transformers, resistors and 
capacitors for channels 0 and 4 are socketed for easy swapping (see the LXT381 data sheet for line 
interface information). Jumper blocks are provided to configure the receive transformer operation 
for 1:1 or 1:2 turns ratio (see 
). Factory installed 
jumpers configure the transformers for a 1:1 ratio.
2.11
Board Protection
The evaluation board provides line surge protection for both the power supply and the line. Two 
transient voltage suppressors (TVS) are included for power supply protection. The E1 line interface 
transmitters are protected with Schottky diodes and the receivers are protected by series input 
resistors. This protection is sufficient for G.703 Annex B compliance.
Figure 3.  Typical Back-End Connector
1
2
3
4
5
6
7
8
GND
RCLK 0
RPOS 0
RNEG 0
TCLK 0
TCLK 0
TPOS 0
TNEG 0
JP1
9
10
GND
LOS 0