Worcester, Mass. Allegro MicroSystems Inc. has introduced a full-bridge motor driver designed to drive low-voltage bipolar brushless DC motors. This fully integrated single-chip A1442 motor driver is said to provide enhanced reliability (including reverse battery protection and output short circuit protection) and eliminate the need for any external support components.
The use of a high-density CMOS semiconductor process allows the integration of all the necessary electronics, said Allegro. This includes the Hall element sensor, the motor control circuitry, and the full output bridge. Low-voltage design techniques have been used to achieve device functionality down to 1.8 V VDD. Commutation of the motor is achieved by use of a single integrated Hall element sensor to detect the rotational position of an alternating-pole ring magnet.
The A1442 uses a soft-switching algorithm to reduce audible switching noise and EMI interference. A micro power sleep mode can be enabled by an external signal to reduce current consumption for battery management in portable electronic devices. This feature allows for the removal of a FET transistor for switching the device on and off. In addition, the device offers an active function for motor braking, which can be used to improve stop/start cycles for caller ID feature in vibration mode.
The A1442 is optimized for vibration motor applications such as cellular phones, pagers, electronic toothbrushes, handheld video game controllers, and low-power fan motors. The small package outline and low profile make this device suitable for use in applications where printed-circuit-board area and component headroom are at a premium.
The A1442 is available in a lead free (Pb free) (Leadframe plating is nickel palladium.) 6-pin MLP micro-leadframe package for surface mount with exposed pad for enhanced thermal dissipation. The 6-pin MLP/DFN (Suffix EW) package measures 1.5 x 2 x 0.4 mm.
Pricing: $0.39 in quantities of 1,000.
Availability: Typical delivery is six to eight weeks.
Product information" brushless DC motor driver
Allegro MicroSystems, Inc., 1-508-853-5000, www.allegromicro.com