Used to Supply both Sensors and Microprocessor Power
Allegro MicroSystems, LLC announces a new three-phase MOSFET driver IC with an integrated low dropout regulator supplying 5 V or 3.3 V. Allegro’s A4919 is designed for a wide range of industrial applications. It can be controlled with block (trapezoidal), sinusoidal, or vector commutation when interfaced with a microprocessor. The A4919 is designed to be a simple direct control gate driver for both the commercial and industrial markets providing LDO for peripherals or a microprocessor and provide complete flexibility over commutation.
A unique charge pump regulator provides full (>10 V) gate drive at power supply voltages down to 7 V and allows the A4919 to operate with reduced gate drive at power supply voltages down to 5.5 V. A bootstrap capacitor is used to provide the above power supply voltage required for the high side N-channel MOSFETs. One logic-level input is provided for each of the six power MOSFETs in the three-phase bridge, allowing motors to be driven with any commutation scheme defined by an external controller. The power MOSFETs are protected from cross-conduction by integrated crossover control.
Motor phase short-to-supply and short-to-ground detection is provided by independent drain-source voltage monitors on each MOSFET. Short faults, supply undervoltage, and chip overtemperature conditions are indicated by a single open-drain fault output. Product variants include either 5.0 V or 3.3 V LDO or an option without LDO and instead provides a voltage input which can be used to monitor an external voltage source.
The A4919 is supplied in a 28-pin TSSOP power package (package type LP) and a 28-terminal 5 mm × 5 mm × 0.90 mm (QFN package) both with an exposed pad for enhanced thermal performance. Both packages are lead (Pb) free, with 100% matte-tin leadframe plating (suffix T).
