DRA722_17 Datasheet, PDF (368/408 Pages) Texas Instruments – Infotainment Applications Processor

DRA722, DRA724, DRA725, DRA726
SPRS956B – MARCH 2016 – REVISED JANUARY 2017
www.ti.com
Item
Carve Ground
Round pads
Routing layer
Table 8-14. TDMS Routing Recommendations (continued)
Description
Reason
Carve GND underneath ESD and CMF
Minimize capacitance under ESD
and CMF
Reduce pad size and round the corners of the pads for the ESD and
CMF components
Minimize capacitance
Route all signals only on the same layer as SoC
Minimize reflection loss
Figure 8-35presents an example layout, demonstrating the “carve GND” concept.
via_{AC Cap}
CMF
via ^{AC Cap}
via
via
CMF
CMF
CM_CMF_F
CMF
Top Layer: Routing from SoC through CMF,
and ESD to connector.
Layer2, GND: Gaps carved in GND underneath,
CMF, ESD, and connector.
Figure 8-35. HDMI Example “carve GND” layout
SPRS85x_PCB_HDMI_3
8.5.4.3 TPD5S115
The TPD5S115 is an integrated HDMI companion chip solution. The device provides a regulated 5 V
output (5VOUT) for sourcing the HDMI power line. The TPD5S115 exceeds the IEC61000-4-2 (Level 4)
ESD protection level.
8.5.4.4 HDMI ESD Protection Device (Required)
Interfaces that connect to a cable such as HDMI generally require more ESD protection than can be built
into the processor’s outputs. Therefore this HDMI interface requires the use of an ESD protection chip to
provide adequate ESD.
When selecting an ESD protection chip, choose the lowest capacitance ESD protection available to
minimize signal degradation. In no case should be ESD protection circuit capacitance be more than 5pF.
TI manufactures these devices that provide ESD protection for HDMI signals such as the TPDxE05U06.
For more information see the www.ti.com website.
8.5.4.5 PCB Stackup Specifications
Table 8-15 shows the stackup and feature sizes required for HDMI.
Table 8-15. HDMI PCB Stackup Specifications
PARAMETER
PCB Routing/Plane Layers
MIN
TYP
MAX
4
6
-
UNIT
Layers
368 Applications, Implementation, and Layout
Copyright © 2016–2017, Texas Instruments Incorporated
Submit Documentation Feedback
Product Folder Links: DRA722 DRA724 DRA725 DRA726