New Industry Products

Allegro MicroSystems Debuts A3948 Motor Driver IC

March 26, 2002 by Jeff Shepard

Allegro MicroSystems Inc. (Worcester, MA) announced a new serially controlled dc motor driver IC. The A3948 features a DMOS H-bridge that is capable of handling continuous currents of ±1.5A and operating voltages to 50V. The DMOS output transistors feature a low RDS(on) rating (270 milliohms typical) and are synchronously rectified during PWM operation for low power dissipation.

The A3948 is controlled via a three-wire serial port. The serial port allows maximum flexibility in configuring the internal PWM current control circuitry to match the motor driving requirements. Also programmable via the serial port are fast, slow and mixed current-decay modes, and the current sense comparator blank time. The A3948 can be put into a sleep mode to minimize power consumption when not in use. Internal circuit protection includes thermal shutdown with hysteresis, crossover-current protection and under-voltage lockout circuitry.

The A3948 is manufactured using Allegro's new ABCD3 (Allegro bipolar CMOS DMOS third generation) process. The A3948SB is offered in a 24-pin DIP and the A3948SLB is offered in a 24-lead SOIC package. Both packages have a 16-week lead time to market and have a copper batwing tab for improved power dissipation.

The A3948 is priced at $1.96 per part for quantities of 5,000.