Power Management User Guide: Agilex™ 5 FPGAs and SoCs

ID 813161
Date 11/04/2024
Public
Document Table of Contents

3.4. Power-On Reset

The power-on reset (POR) circuitry keeps the Agilex™ 5 device in the reset state until the power supply outputs are within the recommended operating range.

A POR event occurs when you power up the Agilex™ 5 device until all power supplies monitored by the POR circuitry reach the recommended operating range within the maximum power supply ramp time, tRAMP . If tRAMP is not met, the Agilex™ 5 device may fail to configure upon power-up .

Figure 3. Relationship Between tRAMP and POR DelayThe boot ROM initialization sequence is part of the POR delay. For tRAMP and POR delay specifications, refer to the Agilex™ 5 FPGAs and SoCs Device Data Sheet .

The Agilex™ 5 POR circuitry uses individual detection circuitry to monitor each of the configuration-related power supplies independently. The POR circuitry is gated by the outputs of all the individual detectors. The SDM POR is gated by the outputs of the SDM associated power detectors.

POR delay is defined as the delay between the last power rail monitored by the POR circuitry from Group 2B to reach the minimum operating condition voltage to the time your device is ready to begin configuration. For POR trip level, you can use the minimum value of the last power supply as a reference.

The Agilex™ 5 device is held in the POR state until all power supplies have passed their trip point. After power supplies have passed the trip point, the Secure Device Manager (SDM) waits for a specific POR delay time and then starts device configuration.