Altera Device-Specific Power Delivery Network - Manual (Page 12)

1–8 Chapter 1: User Guide for the Device-Specific Power Delivery Network (PDN) Tool
Major Tabs of the PDN Tool
Device-Specific Power Delivery Network (PDN) Tool User Guide September 2012 Altera Corporation
Cap Mount
The Cap Mount tab, shown in Figure 1–5 , calculates the capacitor mounting
inductance seen by the decoupling capacitor.
The capacitor mounting calculation is based on the assumption that the decoupling
capacitor is a two-terminal device. The capacitor mounting calculation is applicable to
any two-terminal capacitor with the following footprints: 0201, 0402, 0603, 0805, and
1206. You enter all the information relevant to your layout and the tool provides a
mounting inductance for a capacitor mounted on either the top or bottom layer of the
board. Depending on the layout, you can choose between VOE (Via on End) or VOS
(Via on Side) to achieve an accurate capacitor mounting inductance value.
If you plan to use a footprint capacitor other than a regular two-terminal capacitor or
X2Y capacitor for decoupling, you can skip the Cap Mount tab and directly enter the
capacitor parasitics and capacitor mounting inductance in the Library tab (under the
Custom
field in the Decoupling Cap section of the library). As with the other tabs,
you can save the changes made to the tab, restore the changes, and restore the tab
back to the default settings.
Figure 1–5. Cap Mount Tab