GND cut in mid layer 1
around the LMZ10501
device to reduce noise
coupling
T1
U6
1v1 power rail of the PHY
added as a solid supply plane
below each PHY
Ensure wide traces that
provide the 1v1 and 2v5
power rail
Added additional vias to
insure the best possible
thermal release of LDO
GND cut ring in mid
layer 1 around the LDOs
to further reduce noise
coupling
GND guard ring in mid
layer 1 around the
crystals to further reduce
noise coupling
Design Files
80
JAJU324B – March 2015 – Revised July 2017
翻訳版
—
最新の英語版資料
http://www-s.ti.com/sc/techlit/TIDU832
Copyright © 2015–2017, Texas Instruments Incorporated
EMI/EMC
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リファレンス・デザイン
6.4.4
Layout PHY Power Supply
For the 2.5-V LMZ rail, add a keep-out GND cut in mid layer 1 to decrease noise coupling. To additional
thermal management, add as many vias as possible on the powerPAD of the 1.1-V and 1.8-V LDO and
add an additional thermal release plane on the bottom side of the board.
Ensure wide enough traces when adding the 1.1-V and 2.5-V power rails. The 1.1-V rail is added as a
solid supply plane below each PHY.
shows the PCB layout of TIDA-00204.
図
図
74. Layout Guidelines for PHY Power Supply