Early Power Estimator User Guide

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ID 683272
Date 7/16/2021
Public
Document Table of Contents
Document Table of Contents x
1. Early Power Estimator Overview 2. Setting Up the Early Power Estimator 3. Early Power Estimator Worksheets 4. Factors Affecting the Early Power Estimator Spreadsheet Accuracy A. Additional Information for Early Power Estimator User Guide
1. Early Power Estimator Overview x
1.1. Release Information 1.2. Power Model Status for Supported Device Families
2. Setting Up the Early Power Estimator x
2.1. System Requirements 2.2. Download and Install the Early Power Estimator 2.3. Estimating Power Consumption
2.2. Download and Install the Early Power Estimator x
2.2.1. Changing the Macro Security Level in Microsoft Excel 2003 2.2.2. Changing the Macro Security Level in Microsoft Excel 2007 2.2.3. Changing the Macro Security Level in Microsoft Excel 2010
2.3. Estimating Power Consumption x
2.3.1. Estimating Power Consumption Before Starting the FPGA Design 2.3.2. Estimating Power Consumption While Creating the FPGA Design 2.3.3. Estimating Power Consumption After Completing the FPGA Design
2.3.1. Estimating Power Consumption Before Starting the FPGA Design x
2.3.1.1. Entering Information into the Early Power Estimator
2.3.1.1. Entering Information into the Early Power Estimator x
2.3.1.1.1. Manually Entering Values
2.3.2. Estimating Power Consumption While Creating the FPGA Design x
2.3.2.1. Importing a File
2.3.2.1. Importing a File x
2.3.2.1.1. Generate the EPE File 2.3.2.1.2. Import Data into the EPE Spreadsheet
3. Early Power Estimator Worksheets x
3.1. Main Worksheet 3.2. Logic Worksheet 3.3. RAM Worksheet 3.4. DSP Worksheet 3.5. I/O Worksheet 3.6. PLL Worksheet 3.7. Clock Worksheet 3.8. HSDI Worksheet 3.9. XCVR Worksheet 3.10. HMC Worksheet 3.11. IP Worksheet 3.12. HPS Worksheet 3.13. Report Worksheet 3.14. Enpirion Worksheet
3.1. Main Worksheet x
3.1.1. Input Parameter 3.1.2. Thermal Power 3.1.3. Power Tree Design 3.1.4. Thermal Analysis
3.1.4. Thermal Analysis x
3.1.4.1. Not Using a Heat Sink 3.1.4.2. Using a Heat Sink
3.13. Report Worksheet x
3.13.1. Static Power and Dynamic Current per Voltage Rail 3.13.2. Power Up Current 3.13.3. Power Breakout for Multiple Voltage Supplies 3.13.4. Power Regulator Settings
4. Factors Affecting the Early Power Estimator Spreadsheet Accuracy x
4.1. Toggle Rate 4.2. Airflow 4.3. Temperature 4.4. Heat Sink
A. Additional Information for Early Power Estimator User Guide x
A.1. Document Revision History for Early Power Estimator User Guide
1. Early Power Estimator Overview
2. Setting Up the Early Power Estimator
3. Early Power Estimator Worksheets
4. Factors Affecting the Early Power Estimator Spreadsheet Accuracy
A. Additional Information for Early Power Estimator User Guide

3.1.4.1. Not Using a Heat Sink

When you do not use a heat sink, the major paths of power dissipation are from the device to the air. You can refer this as a junction-to-ambient thermal resistance. In this case, there are two significant junction-to-ambient thermal resistance paths:
  • From the device through the case to the air
  • From the device through the board to the air
Figure 6. Thermal Representation without a Heat Sink

In the model used in the EPE spreadsheet, power is dissipated through the case and board. The θJA values are calculated for differing air flow options accounting for the paths through the case and through the board.

Figure 7. Thermal Model in the EPE Spreadsheet without a Heat Sink

The ambient temperature does not change, but the junction temperature changes depending on the thermal properties; therefore the junction temperature calculation is an iterative process.

The following equation shows the total power calculated based on the total θJA value, ambient, and junction temperatures.

Figure 8. Total Power
Level Two Title