Microchip Technology MEC172 Series Layout Manual

PCB Layout Guide for MEC172x

Author: Tom Rubino
Microchip Technology Inc.
INTRODUCTION
This application note provides information on design considerations for a printed circuit board (PCB) for the Microchip
MEC1721/MEC1723 device.
The design of the PCB requires care to provide good supply and ground paths; in addition, other design issues are
addressed in this document.
The functional blocks in the MEC1721/MEC1723 have different requirements for routing and external connections,
which are also outlined in this application note.
Please see References for device-level information such as V
for the 176-Pin WFBGA.
This document includes the following topics:
• Section 1.0, "General Layout Considerations," on page 2
• Section 2.0, "Miscellaneous Considerations," on page 9
• Section 3.0, "JTAG Design and Layout Guide," on page 24
• Section 4.0, "Boards bring-up debug tips," on page 29
Audience
This document is written for a reader that is familiar with hardware design. The goal of this application note is to provide
information about sensitive areas of the MEC1721/MEC1723 PCB layout.
References
The following documents should be referenced when using this application note. Please contact your Microchip repre-
sentative for availability.
• Microchip MEC1721/MEC1723 Data Sheet
• Microchip MEC1721/MEC1723 EVBs, ASSY. 6906A
• PCI Local Bus Specification (see www.pcisig.com)
2
• I C-bus specification and user manual, Rev. 6 - 4 April, 2014 or later (see
UM10204.pdf)
• Intel, Enhanced Serial Peripheral Interface (eSPI) Specification (for Client Platform)
• Microchip "eSPI Controller" Specification
Package Information
The MEC1721/MEC1723 device is currently available in the following packages:
• MEC1721/MEC1723 for 176-pin, WFBGA/LJ
• MEC1721/MEC1723 for 144-pin, WFBGA/SZ
 2021 Microchip Technology Inc. and its subsidiaries
AN3759
power planes, and mechanical package information
CC1
www.nxp.com/documents/user_manual/
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