Three-Phase BLDC Controller and MOSFET Driver IC

Allegro MicroSystems Europe has announced a three-phase brushless BLDC motor controller for use with N-channel external power MOSFETs.  Allegro’s AMT49413 incorporates much of the circuitry required to design a cost-effective, three-phase motor drive system with maximum supply voltages up to 50 V. 

This device is targeted at high current BLDC motor applications for speed, position, or torque control requirements.  It has been designed for battery powered power tools, lawn and garden equipment and factory automation, pumps, fans, blowers and appliance applications within the consumer and industrial markets.

The AMT49413 provides functionality over a wide input supply range. A unique charge pump regulator provides adequate (>10 V) gate drive for battery voltages down to 7 V, and allows the device to operate with a reduced gate drive at supply voltages down to 5.5 V.  A bootstrap capacitor is used to provide the above-battery supply voltage required for N-channel MOSFETs.  An internal charge pump for the high-side drive allows for DC (100% duty cycle) operation.

Internal fixed-frequency PWM current control circuitry can be used to regulate the maximum load current. The peak load current limit is set by the selection of an input reference voltage and external sensing resistor. The PWM frequency is set by a user-selected external RC timing network. For added flexibility, the PWM input can be used to provide speed and torque control, allowing the internal current control circuit to set the maximum current limit.  Efficiency is enhanced by using synchronous rectification.

A full suite of protection features is provided including MOSFET shoot-through, undervoltage, overvoltage, HALL logic fault, low motor current and short to ground, supply and across motor winding. The dead time can be set by a single external resistor.

About Allegro MicroSystems

Allegro MicroSystems, LLC is a leader in developing, manufacturing and marketing high-performance semiconductors. Allegro’s innovative solutions serve high-growth applications within the automotive market, with additional focus on office automation, industrial, and consumer/communications solutions. Allegro is headquartered in Worcester, Massachusetts (USA) with design, applications, and sales support centers located worldwide.

Allegro MicroSystems Europe, headquartered in Chertsey, United Kingdom, is the European sales and marketing operation, and operates a network of representatives and distributors throughout Europe. Allegro also has an engineering design centre in Edinburgh in Scotland and an application and marketing centre in Annecy in France.