Datasheet

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DP83849C
5.0 Design Guidelines
5.1 TPI Network Circuit
Figure 12 shows the recommended circuit for a 10/100
Mb/s twisted pair interface.
Below is a partial list of recommended transformers. It is
important that the user realize that variations with PCB and
component characteristics requires that the application be
tested to ensure that the circuit meets the requirements of
the intended application.
Pulse H1102
Pulse H2019
Belfuse S558-5999-U7
Halo TG110-S050N2RL
Figure 12. 10/100 Mb/s Twisted Pair Interface
RJ45
TPRDM
TDRDP
TPTDM
TPTDP
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