Power Management User Guide: Agilex™ 5 FPGAs and SoCs

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

4.3.3. Temperature Monitor Design Guidelines

You can measure the on-chip temperature of the core fabric through the remote TSDs while the device is powered on or powered off. However, the local temperature sensors are available only after the device is powered up and configured.
  • Connect the remote TSD pins to external temperature sensing devices to monitor the on-chip temperature.
  • To interface with the remote TSD, use temperature sensing chips with features that allow you to perform calibration and measurement compensation to improve accuracy, such as:
    • Configurable ideality factor
    • Offset adjustment with or without Beta compensation
  • Keep the resistance of both board traces to the remote TSD p and n pins to less than 0.2 Ω.
  • Route both traces in equal lengths and shield them.
  • Altera recommends a 10-mils width and space for both traces.
  • Route both traces through the most minimum number of vias and crossunders possible to minimize the thermocouple effects.
  • Ensure that the number of vias for both traces are the same.
  • To avoid coupling, insert a GND plane between the remote TSD pins traces and high-frequency toggling signals, such as clocks and I/O signals.
  • To filter high-frequency noise, place an external capacitor between the traces close to the external sensors.
  • If you use only the local temperature sensors, you can leave the remote TSD p and n pins unconnected.

For details about device specifications and connection guidelines, refer to the external temperature sensor manufacturer's documentation.