A new three-phase MOSFET driver IC with an integrated low dropout regulator supplying 5V or 3.3V has been introduced by Allegro MicroSystems. The A4919 is designed for a wide range of industrial applications, and 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 charge pump regulator provides full (more than 10V) gate drive at power supply voltages down to 7V and allows the A4919 to operate with reduced gate drive at power supply voltages down to 5.5V. 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 under voltage, and chip over temperature conditions are indicated by a single open-drain fault output. Product variants include either 5.0V or 3.3V 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 5×5×0.90mm (QFN package) both with an exposed pad for enhanced thermal performance. Both packages are lead (Pb) free, with 100% matt-tin leadframe plating (suffix T).