XRT59L921 Datasheet, PDF (25/32 Pages) Exar Corporation – TWENTY-ONE CHANNEL E1 LINE INTERFACE UNIT

REV. 1.2.1
TRANSFORMER RECOMENDATION
XRT59L921
TWENTY-ONE CHANNEL E1 LINE INTERFACE UNIT
RECEIVE TRANSFORMER RECOMMENDATIONS
PARAMETER
Turns Ratio
Primary Inductance
Isolation Voltage
Leakage Inductance
VALUE
1:1
2.2 Interfacing the XRT59L921 Receive Section to the Line (Capacitive Coupling)
Figure 11 and Figure 12 are recommended methods to Interface the the receive sections of the XRT59L921to
the line.
FIGURE 11. RECOMMENDED 75Ω CAPACITIVE COUPLING APPLICATION
RxPOS_n
XRT59L921
RTIP_n
RxPOS_n
0.1 µF
Coaxial Cable
RxNEG_n
RxNEG_n
150 Ω
150 Ω
LOS_n
LOS_n
RRING_n
0.1 µF
FIGURE 12. RECOMMENDED 120Ω TWISTED PAIR CAPACITIVE COUPLING APPLICATION
RxPOS_n
RxNEG_n
XRT59L921
RTIP_n
RxPOS_n
RxNEG_n
0.1 µF
240 Ω
240 Ω
120 Ω Twisted
Pair Cable
LOS_n
LOS_n
RRING_n
0.1 µF
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