Worcester, Mass.Allegro MicroSytems Inc. has introduced two full-bridge motor drivers designed to drive low-voltage brushless DC motors in applications that require rotor speed control and fast rotor start-stop cycles.
A high density CMOS semiconductor process allows the integration of a Hall element, an H-bridge output driver and PWM speed control logic into a monolithic IC. The devices provide reverse battery protection and output short circuit protection. The small package outline and low profile make these devices well-suited for use in communication and consumer applications where PCB area and component headroom are at a premium.
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. Low-voltage design techniques have been employed to achieve full device functionality down to 1.8 V VDD. The voltage applied to the PDC pin is used to externally control the maximum speed of the motor by adjusting the internal PWM duty cycle of the output driver.
Allegro's A1444/A1445 devices employ a soft-switching algorithm to reduce audible switching noise and EMI interference. The A1444 and A1445 have different, selectable internal PWM Duty Cycle options to accommodate a wide range of motor designs by controlling the state of the PDC input pin, providing external control.
Allegro's A1444 and A1445 motor drivers are available in a lead free (leadframe plating Nickel Palladium) 6-pin MLP micro-leadframe package for surface mount assembly.
Pricing:$0.58 in quantities of 1,000.
Availability: Six to eight-week typical lead-time to market.
Datasheets: Click here.
Allegro MicroSystems Inc., www.allegromicro.com