11 Introduction

A Rate Limiter controls the rate of change of variable and is used to avoid abrupt change of values that causes transient and jerky operation. Rate Limiter is generally used to generate a smooth speed profile while changing from one speed range to another speed range.

Summary

The following table provides a summary of the Rate Limiter IP characteristics.

Core VersionThis document applies to Rate Limiter v4.2.
Supported Device Families
  • PolarFire® SoC
  • PolarFire
  • RTG4™
  • IGLOO® 2
  • SmartFusion® 2
Supported Tool FlowRequires Libero® SoC v11.8 or later releases.
LicensingComplete encrypted RTL code is provided for the core, enabling the core to be instantiated with SmartDesign. Simulation, Synthesis, and Layout can be performed with Libero software. Rate Limiter is licensed with encrypted RTL that must be purchased separately. For more information, see Rate Limiter.

Features

Rate Limiter has the following key features:

  • Provides a smooth speed profile
  • Slope is configured with a rate count and a slew count

Implementation of IP Core in Libero Design Suite

IP core must be installed to the IP Catalog of the Libero® SoC software. This is done automatically through the IP Catalog update function in the Libero SoC software, or the IP core can be manually downloaded from the catalog. Once the IP core is installed in the Libero SoC software IP Catalog, the core can be configured, generated, and instantiated within the SmartDesign tool for inclusion in the Libero project list.