DP83849C_08 Datasheet, PDF (35/98 Pages) National Semiconductor (TI) – PHYTER® DUAL Commercial Temperature Dual Port 10/100 Mb/s Ethernet Physical Layer Transceiver

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
TPRDM
49.9Ω
TDRDP
49.9Ω
Vdd
0.1µF
TPTDM
49.9Ω
TPTDP
49.9Ω
Vdd
0.1µF
PLACE RESISTORS AND
CAPACITORS CLOSE TO
THE DEVICE.
Vdd
COMMON MODE CHOKES
MAY BE REQUIRED.
1:1
0.1µF*
0.1µF*
1:1 ^T1
RD-
RD+
TD-
TD+
RJ45
NOTE: CENTER TAP IS PULLED TO VDD
*PLACE CAPACITORS CLOSE TO THE
TRANSFORMER CENTER TAPS
All values are typical and are +/- 1%
Figure 12. 10/100 Mb/s Twisted Pair Interface
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