AN2839 Datasheet, PDF (1/40 Pages) STMicroelectronics – L6228 fully-integrated two-phase stepper motor driver

AN2839
Application note
L6228 fully-integrated two-phase stepper motor driver
Introduction
Modern motion control applications need more flexibility, which can only be addressed with
specialized IC products. The L6228 is a fully-integrated stepper motor driver IC specifically
developed to drive a wide range of two-phase (bipolar) stepper motors. This IC is a one-
chip, cost-effective solution that includes several unique circuit design features. These
features, including a decoding logic that can generate three different stepping sequences,
allow the device to be used in many applications, including microstepping. The principal aim
of this development project was to produce an easy-to-use, fully-protected power IC. In
addition, several key functions, such as protection circuitry and PWM current control,
drastically reduce the number of external components to meet requirements for many
different applications.
The L6228 is a highly-integrated, mixed-signal power IC that allows the user to easily design
a complete motor control system for two-phase bipolar stepper motors. Figure 1 shows the
L6228 block diagram. The IC integrates eight Power DMOS’s, a centralized logic circuit that
implements the phase generation and a constant t_OFF PWM current control technique
(quasi-synchronous mode) for each of the two phases of the motor, plus other added
features for safe operation and flexibility.
Figure 1. L6228 block diagram
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September 2009
Doc ID 15104 Rev 1
1/40
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