Owner's manual

DS21455/DS21458 Quad T1/E1/J1 Transceivers
173 of 270
25.8 Recommended Circuits
Figure 25-5. Basic Interface
NOTES:
1) All resistor values are ±1%.
2) Resistors R should be set to 60Ω each if the internal receive-side termination feature is enabled. When
this feature is disabled, R = 37.5Ω for 75Ω coaxial E1 lines, 60Ω for 120Ω twisted pair E1 lines, or
50Ω for 100Ω twisted pair T1 lines.
3) C = 1µF ceramic.
TTIP
TRING
RTIP
RRING
DVDD
TVDD
RVDD
V
DD
DVSS
TVSS
RVSS
DS21455/458
R R
2:1
1:1
C
0.1mF
0.1mF
0.1mF
0.01mF
TRANSMIT
LINE
RECEIVE
LINE
0.1mF
10mF
10mF
+
+