Intel® Agilex™ Device Configuration via Protocol (CvP) Implementation User Guide

ID 683763
Date 10/04/2021
Public

A newer version of this document is available. Customers should click here to go to the newest version.

Document Table of Contents

4.1.1. FPGA Power Supplies Ramp Time Requirement

For an open system, you must ensure that your design adheres to the FPGA power supplies ramp-up time requirement.

The power-on reset (POR) circuitry keeps the FPGA in the reset state until the power supply outputs are in the recommended operating range. A POR event occurs from when you power up the FPGA until the power supplies reach the recommended operating range within the maximum power supply ramp time, tRAMP . If tRAMP is not met, the device I/O pins and programming registers remain tri-stated, during which device configuration can fail.

To meet the PCIe* link up time for CvP, the total tRAMP must be less than 10 ms, from the first power supply ramp-up to the last power supply ramp-up. You must select ASx4 fast mode for MSEL settings to make sure the shortest POR delay.

Figure 5. FPGA Power Supplies Ramp-Up Time and POR