GND cut in mid layer
1 around the
LM46002 device to
reduce noise coupling
U1
Current loop as small as possible
Noise sensitive signals removed
from noisy ground plane
J1
Vias around the GND
cut to reduce noise
coupling
Design Files
81
JAJU324B – March 2015 – Revised July 2017
翻訳版
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最新の英語版資料
http://www-s.ti.com/sc/techlit/TIDU832
Copyright © 2015–2017, Texas Instruments Incorporated
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6.4.5
Layout of the 24-V to 5-V DC/DC Buck (LM46002)
Follow the layout guidelines from the LM46002 data sheet. Cut out layer 1 under LM46002 to avoid
coupling into other layers. Ensure that current loop of the device is maintained as small as possible. The
example layout of the LM46002 on TIDA-00204 is shown in
.
図
図
75. Layout Guidelines for 24-V to 5-V DC/DC Buck With LM46002
6.4.6
Layout Sitara Power Supply
For the Sitara power supply, the following guidelines were considered.
Routing the power tracks to the Sitara each power track as a GND plane as reference GND, mid layer 4
used as supply layer with supply planes for each high current power track. VMMC, VAUX33, and VAUX1
power track added in mid layer 2 and VDIG2 and VPLL power track added in mid layer 6.
VDAC intentionally does a u-trace as the DAC functionality is not used. If this functionality is needed, add
additional traces for this power rail.