DS33R11 Ethernet Mapper with Integrated T1/E1/J1 Transceiver
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10.24 Recommended Circuits

Figure 10-7. Basic Interface

Refer to Application Note 324: T1/E1 Network Interface Design for more information on protected interfaces.
TTIP
TRING
RTIP
RRING
DVDD
TVDD
RVDD
VDD
DVSS
TVSS
RVSS
DS33R11
R R
2:1
1:1
C

0.1μF

0.1μF

0.1μF

0.01μF

TRANSMIT
LINE
RECEIVE
LINE

0.1μF

10μF

10μF

+
+
NOTE 1: ALL RESISTOR VALUES ARE ±1%.
NOTE 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.
NOTE 3: C = 1μF CERAMIC.

Table 10-13. Transformer Specifications

SPECIFICATION RECOMMENDED VALUE
Turns Ratio 3.3V Applications 1:1 (receive) and 1:2 (transmit) ±2%
Primary Inductance 600μH (min)
Leakage Inductance 1.0μH (max)
Intertwining Capacitance 40pF (max)
Transmit Transformer DC Resistance
Primary (Device Side)
Secondary
1.0 (max)
2.0 (max)
Receive Transformer DC Resistance
Primary (Device Side) 1.2 (max)
Secondary 1.2 (max)