New Industry Products

Allegro Debuts A3932 Power MOSFET Controller

December 12, 2002 by Jeff Shepard

Allegro MicroSystems Inc. (Worcester, MA) introduced a new three-phase power MOSFET controller with high-current gate drive capability that drives a wide range of power discrete n-channel MOSFETs and supports motor supply voltages from 12V to 50V. The A3932 integrates a bootstrapped high-side driver to minimize the external component count required to drive the n-channel MOSFETs.

Internal fixed, off-time, pulse-width modulated, current control circuitry can be used to regulate the maximum load current to a desired value for speed/torque control. The A3932 features an adjustable cross-over delay for cross-conduction protection. The A3932 synchronous rectification circuitry minimizes the power dissipation in the discrete MOSFETs, eliminating the need for external power clamp diodes and allows for a more economical choice for the n-channel MOSFET drivers.

The A3932 provides commutation logic to directly interface Hall sensors configured for 120-degree spacing. The Hall input pins are pulled up to an internally generated 5V reference. Power MOSFET protection features include a bootstrap capacitor charging current monitor, an under-voltage monitor, a motor lead short-to-ground, and thermal shutdown.

The A3932 is manufactured using Allegro's new Allegro Bipolar CMOS DMOS 3rd generation (ABCD3) process, and is targeted to meet the needs of the office automation, industrial, consumer and medical equipment markets. The A3932 is offered in a 32-lead PLCC package, has a 10 to 12 week lead-time to market, and is priced at $3.11 per part in quantities of 10,000.