External Memory Interfaces Agilex™ 7 M-Series FPGA IP User Guide

ID 772538
Date 11/18/2024
Public
Document Table of Contents

7.6.9. DDR5 RDIMM Power Management IC

DDR5 RDIMM modules contain their own on-module power management IC (PMIC), which conserves board space and eliminates a need for voltage regulators on the motherboard.

The PMIC has two supply inputs, a VIN_Mgmt supply and a VIN_Bulk supply. The PMIC features four step-down swicthing regulators and three LDO regulators. The PMIC is powered from the VIN_Bulk input for switching regulators and VIN_Mgmt for the rest of the PMIC, including LDO voltages.

The Agilex™ 7 M-Series calibration algorithm does not support PMIC configuration and bring-up; you are required to perform these activities yourself. The following outlines the power-on sequence that the host must perform:

  1. Ramp up VIN_Mgmt supply and VIN_Bulk supply; these may come up in either order, but VIN_Mgmt must be present for the PMIC to work. The recommendation is to ramp up VIN_Mgmt first. (The JEDEC PMIC50x0 Power Management IC Standard defines ramp-up and ramp-down rate limits and threshold for voltage delivered to PMIC VIN_Bulk and VIN_Mgmt).
  2. Hold VIN_Mgmt supply stable for the minimum of time defined in the JEDEC PMIC50x0 Power Management IC Standard.
  3. Hold VIN_Bulk supply stable for the minimum of time defined in the JEDEC PMIC50x0 Power Management IC Standard.
  4. Query the status of the PMIC status register to determine whether it is safe to enable VR.
  5. If it is safe to enable, send the VR Enable command.

For detail information on PMIC features, input/output electrical characteristics, register set and complete power-up sequence, refer to the JEDEC PMIC50x0 Power Management IC Standard.