Datasheet

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DP83865
5.0 Design Guide (Continued)
to result in signal quality failure as well as creating EMI
problems.
Figure 15. Power Supply Filtering
Figure 16. 1.8V voltage regualtor placement.
DP83865
18 Ω
V
DD
= 1.8 V
0.01 µF
Typical supply bypassing
Low pass filter for
22 µF
1V8_ AVDD2
GND
0.1 µF
IO_ VDD
GND
(Near pins of the device)
2V5_ AVDD1
GND
BG_REF
9.76 k Ω
0.01 µ F
1V8_AVDD2 only
0.01 µF
CORE_ VDD
0.1 µF
0.01 µ F
V
DD
= 1.8 V
GND
0.01 µ F
1%
1V8_AVDD1
GND
V
DD
= 2.5 V
0.01 µ F
V
DD
= 2.5 V
2V5_AVDD2
GND
10 Ω
V
DD
= 1.8 V
Low pass filter for
22 µF
1V8_AVDD3 only
1V8_ AVDD3
GND
DP83865 and GMAC PCI NIC Card
PHY
MAC
2.5 1.8
Analog section
Digital section