Altera Power Delivery Network - Manual (Page 9)

Chapter 1: Power Delivery Network (PDN) Tool User Guide 1–5
Setting Up the PDN Tool
© March 2009 Altera Corporation Power Delivery Network (PDN) Tool User Guide
Figure 1–4 shows the various components (VRM, Spreading, BGA Via, and Plane
Cap) of the PDN. In the Decap Selection tab, select the option most applicable for
your design to begin the analysis for a given power supply. In this example, use the
values populated in the Custom field in the Library tab, choose the Custom setting
for the various parameters in the Decap Selection tab.
The following information helps you accurately calculate the Z
TARGET
for any power
rail:
■ The maximum transient current requirements for all devices in the system that are
powered by the power rail under consideration. You can obtain this information
from the manufacturers of the respective devices.
1 Altera provides the PowerPlay Early Power Estimator (EPE) tool to
estimate power consumption for all its FPGA and CPLD devices. You can
download the EPE tool from the
PowerPlay Early Power Estimator
Downloads for your target Altera device. You can also use the Quartus ® II
PowerPlay Power Analyzer for an accurate estimation when the design is
implemented.
■ The maximum allowable AC ripple on the power rail as a percentage of the supply
voltage. You can obtain this information from the power supply tolerance
specifications of the devices being supplied by the power rail under consideration.
■ Information regarding the Frequency Target (F
TARGET
) to which the board PDN
decoupling needs to be effective.
Figure 1–4. Options for the PDN Components