Datasheet

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DP83848T
5.0 Design Guidelines
5.1 TPI Network Circuit
Figure 11 shows the recommended circuit for a 10/100
Mb/s twisted pair interface. To the right is a partial list of
recommended transformers. It is important that the user
realize that variations with PCB and component character-
istics requires that the application be tested to ensure that
the circuit meets the requirements of the intended applica-
tion.
Pulse H1102
Pulse H2019
Pulse J0011D21
Pulse J0011D21B
Figure 11. 10/100 Mb/s Twisted Pair Interface
RJ45
RD-
RD+
TD-
TD+
RD-
RD+
TD-
TD+
1:1
0.1µF*
T1
1:1
COMMON MODE CHOKES
MAY BE REQUIRED.
49.9Ω
49.9
Ω
0.1µF*
Vdd
NOTE: CENTER TAP IS PULLED TO VDD
*PLACE CAPACITORS CLOSE TO THE
TRANSFORMER CENTER TAPS
0.1µF
All values are typical and are +/- 1%
PLACE RESISTORS AND
CAPACITORS CLOSE TO
THE DEVICE.
Vdd
49.9Ω
49.9
Ω
0.1µF
Vdd