Document revision history – Altera Device-Specific Power Delivery Network User Manual
Page 28
Realistic tool entry can make decoupling easier to achieve. The following factors affect the calculation of
Z
TARGET
:
• An increase in dynamic current reduces Z
TARGET
and makes decoupling difficult to achieve. See the
guidelines above.
• Enter realistic noise or ripple figures into the PDN tool. Use the noise figure listed in the device and
rail specific table in the Introduction tab of the PDN Tool. You should not use the DC specification
from the device datasheet. Unrealistic ripple requirements reduce Z
TARGET
and make decoupling
difficult.
• Enter realistic transient % figures into the PDN tool. Use the transient % figure listed in the device and
rail specific table in the Introduction tab of the PDN Tool. Unrealistic transient % requirements
reduce Z
TARGET
and make decoupling difficult.
Document Revision History
Date
Version
Changes
March 2015
2015.03.06
Made the following changes:
• Added MAX 10 to the list of supported devices in the Overview
section.
• Changed the "Device Selection" figure.
• Clarified options for entering power supply voltage in the
Power Rail Data and Configuration Section section.
• Changed the "Power Rail Data and Power Sharing Scheme
Section" figure.
• Added new parameters and descriptions to the Rail Group
Summary Section section.
• Added a note to the Cap_Mount section.
• Added the Troubleshooting Z
EFF
and Strategies for Correcting
High Z
EFF
sections.
September 2014
2014.09.29
• Added notes to the "PDN Topology Modeled as Part of the
Tool" figure.
• Added detailed explanation of the options availabe in the VRM
Impedence pull-down menu in the "VRM Impedence Section."
September 2014
2014.09.12
Initial release.
28
Document Revision History
UG-01157
2015.03.06
Altera Corporation
Device-Specific Power Delivery Network (PDN) Tool 2.0 User Guide