Agilex™ 7 Power Management User Guide

ID 683373
Date 11/25/2024
Public
Document Table of Contents

2.2. Power Estimation Basics

The Altera power analysis features, including the Power and Thermal Calculator tool and the Quartus® Prime software Power Analyzer, give you the ability to estimate power consumption from early design concept through design implementation, as shown in the following figure.

As you provide more details about your design characteristics, estimation accuracy is improved. Altera recommends that you switch from the Power and Thermal Calculator to the Power Analyzer in the Quartus® Prime software once your design is available. The Power Analyzer produces more accurate results because it has more detailed information about your design, including routing and configuration information about all the resources in your design.

The accuracy of the power model is determined on a per-power-rail basis for both the Power Analyzer and the Power and Thermal Calculator.

For most designs, the Power Analyzer and the Power and Thermal Calculator have the following accuracies, with final power models:

  • Power Analyzer—within 10% of silicon for the majority of power rails and the highest power rails, assuming accurate inputs and toggle rates.
  • Power and Thermal Calculator—within 15% of silicon for the majority of power rails and the highest power rails, assuming accurate inputs and toggle rates. Recommended margins are shown in the Report tab, only after device power model status is final.
Figure 1. Power Analysis from Design Concept Through Design Implementation
Table 1.  Comparison of Power and Thermal Calculator and Quartus® Prime Power Analyzer Capabilities
Characteristic Power and Thermal Calculator Quartus® Prime Power Analyzer
When to use Any time
Note: For post-fit power analysis, you get better results with the Quartus® Prime Power Analyzer.
Post-fit
Software requirements
  • The Quartus® Prime software
  • The Power and Thermal Calculator
    • Available in a standalone version which offers the same features as the Power and Thermal Calculator version integrated within the Quartus® Prime software
The Quartus® Prime software
Accuracy Medium Medium to very high
Data inputs
  • Resource usage estimates
  • Clock requirements
  • Environmental conditions
  • Toggle rates
  • Post-fit design
  • Clock requirements
  • Signal activity defaults
  • Environmental conditions
  • Register transfer level (RTL) simulation results (optional)
  • Post-fit simulation results (optional)
  • Signal activities per node or entity (optional)
Data outputs
  • Total thermal power dissipation
  • Thermal static power
  • Thermal dynamic power
  • Off-chip power dissipation
  • Current drawn from voltage supplies
  • Total thermal power dissipation
  • Thermal static power
  • Thermal dynamic power
  • Thermal I/O power
  • Thermal power by design hierarchy
  • Thermal power by block type
  • Thermal power dissipation by clock domain
  • Off-chip (non-thermal) power dissipation
  • Current drawn from voltage supplies