Allegro MicroSystems Inc. (Worcester, MA) announced its next-generation pulse-width-modulated (PWM), current-controlled, single full-bridge motor-driver IC based on DMOS technology. The new A3959 offers low Rds(on) outputs, synchronous rectification, mixed-decay PWM current control, high peak currents and fast switching speeds.
Designed for PWM current control of dc motors, the A3959 is capable of output currents up to +/-3A and operating voltages up to 50V. The internal, fixed, off-time PWM current control can be set to either slow, fast or mixed-decay mode. Allegro's patented mixed-decay mode is claimed to reduce the high ripple-current effects of fast decay, and minimize the limited bandwidth issues of slow decay by adjusting the percent of off-time spent in each mode by the use of a percent-fast-decay pin. PHASE and ENABLE input terminals are provided for use in controlling the speed, torque and direction of the dc motor.
The A3959 offers sleep- or idle-mode input to minimize power consumption when not in use. It is targeted for the industrial and office-equipment marketplace with end-appplications, including copiers, medical equipment, vending machines, robotics and industrial automation.
Allegro's A3959 is available in two packages, a 24-lead plastic DIP and a 24-lead plastic SOIC. The device has a 16-week lead time to market and will be priced at $2.27 per part for quantities of 1,000.
