Global Sources
EE Times-Asia
Stay in touch with EE Times Asia
EE Times-Asia > Controls/MCUs

PWM motor driver targets automation, industrial markets

Posted: 20 Sep 2006 ?? ?Print Version ?Bookmark and Share

Keywords:Allegro? A3992? microstepping PWM motor driver?

Allegro MicroSystems Inc. has announced the A3992, a DMOS full-bridge microstepping PWM motor driver targeted at the office automation and industrial markets. The new solution offers over-current protection (OCP); synchronous rectification for low power dissipation; patented programmable mixed, fast and slow current decay modes; and low on resistance DMOS outputs, in a thermally efficient surface mount package.

Designed for PWM current control of bipolar microstepping stepper motors, the device is capable of continuous output currents to 1.5A and operating voltages to 50V. Internal fixed off-time PWM current control timing circuitry can be programmed via the serial interface to operate in slow, fast and mixed decay modes.

The desired load current level is set via the serial port with two 6bit linear DACs in conjunction with a reference voltage. The six bits of control allow maximum flexibility in torque control for a variety of step methods, from microstepping to full step drive. Load current is set in 1.56 percent increments of the maximum value.

Synchronous rectification circuitry allows the load current to flow through the low Rds(on) of the DMOS output driver during current decay. This feature eliminates the need for external clamp diodes in most applications, saving cost and external component count, while minimizing power dissipation, the company said.

Allegro's A3992 is supplied in a 1.1mm 24L eTSSOP (suffix 'LP') with exposed power tab and a 24-lead plastic DIP with a copper batwing tab (suffix 'B'). The power tab is at ground potential and needs no electrical isolation.

Article Comments - PWM motor driver targets automation,...
*? You can enter [0] more charecters.
*Verify code:


Visit Asia Webinars to learn about the latest in technology and get practical design tips.

Back to Top