AN4158 Datasheet, PDF (1/34 Pages) STMicroelectronics – Peak current control with automatic decay adjustment

AN4158
Application note
Peak current control with automatic decay adjustment and
predictive current control: basics and setup
Enrico Poli
Introduction
The new STMicroelectronics L6472 and L6474 motor drivers provide two new patented
advanced current control systems evolving from traditional peak current control systems:
automatic decay adjustment and the predictive current control.
Using automatic decay adjustment, the L6472 and L6474 devices allow current ripple to be
reduced and control robustness to be increased especially in microstepping applications.
The predictive current control regulates the average current instead of the peak current,
obtaining a more precise positioning, and reduces the variation of the power stage switching
frequency.
Automatic decay adjustment and predictive current control allow stepper motors to be
operated with less torque ripple, fewer vibrations and much more smoothly at low speed.
This document describes the basic principles and the operation of the new control systems
and provides suggestions on parameter setup in order to obtain optimal results.
April 2015
DocID023635 Rev 2
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