AN4144 is an application note published by ST, which introduces the principle and parameter optimization method of voltage mode driving.
This document describes the operating principles of Voltage mode driving, a patented method by STMicroelectronics that improves stepper motor performance by applying sinusoidal voltage to the motor phases. It details how this open-loop control approach achieves smoother operation and higher micro-stepping resolution compared to classic current mode driving.
The note provides specific strategies for regulating control parameters to fit application requirements, including compensation for back electromotive force (BEMF), motor supply voltage variations, and thermal drift of phase resistance. It also investigates common issues such as motor resonances and offers practical solutions like damping, current reduction, and acceleration adjustments.
The document describes Voltage mode driving, which is a patented stepper motor driving method by STMicroelectronics.
The best performance is always obtained using microstepping operation, as Voltage mode driving is not suited to full step driving.