Derive Decoupling In A Single-Rail Scenario - Altera Stratix IV GX Manual

Chapter 1: Power Delivery Network (PDN) Tool User Guide for Stratix IV Devices
Design PCB Decoupling Using the PDN Tool
Figure 1–14. Library Tab Fields
Notes to
The numbers correspond to the following steps 1, 2, 3, 4, 5.
(1) Enter the ESR, ESL, and Lmnt values for the capacitors under the Custom field.
(2) Enter the effective BGA via (loop) parasitics for the power supply being decoupled.
(3) Enter the plane capacitance seen by the power/ground plane pair on the board for the power supply under Plane Cap.
(4) Enter the VRM parasitics, if available, under the Custom row.
(5) Enter the effective spreading inductance seen by the decoupling capacitors in Custom row.

Derive Decoupling in a Single-Rail Scenario

A power supply connects to only one power rail on the FPGA device in a single-rail
scenario. The PDN noise is created by the transient current of the single rail. You
determine Z
only.
You must follow the steps below to derive the desired capacitor combination:
1. Select the device/power rail to work with.
2. Select the parameter setting for the PDN components.
3. Enter the electric parameters to set Z
4. Derive the PCB decoupling scheme.
© March 2009 Altera Corporation
Figure 1–14:
and F based on the parameters related to the selected rail
TARGET EFFECTIVE
and F
TARGET EFFECTIVE.
Power Delivery Network (PDN) Tool for Stratix IV Devices User Guide
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