A4919 Three-Phase Controller from Allegro

     Allegro's A4919 is designed for a wide range of industrial applications, including lawn and garden equipment and battery-operated power tools. The control input of the A4919 provides a simple solution for many motor drive applications controlled by an external microcontroller or DSP. The bootstrap capacitor provides the required battery supply voltage to the n-channel external power MOSFET. Power MOSFETs prevent transconductance by integrating crossover control.

     To enable the A4919 to operate with gate drive voltages as low as 5.5 V, a unique charge pump regulator provides full (>10 V) gate drive for battery voltages as low as 7 V. The A4919 also contains an on-board voltage regulator that can be used to power sensors and microprocessors. A three-phase bridge allows the motor to be driven using any communication scheme defined by an external controller.

     Short circuit faults, supply undervoltage and die overtemperature conditions are indicated by a single open-drain fault output. If the internal temperature of the device rises high enough, an overtemperature warning is generated, at which point the regulator shuts down immediately and a FAULT flag is generated. All device functions except the voltage regulator remain powered on. The continuous operating junction temperature of the A4919 is +165°C.