Date: 01/08/2011

Automotive grade three phase MOSFET pre-driver IC for BLDC motors

Allegro has announced a latest automotive grade three phase MOSFET pre-driver IC A4933 targeted at BLDC motors found in electronic power steering systems, engine cooling fans, transmission actuators and hydraulic pumps.

Allegro says A4933 is targeting three-phase systems where high power, high torque and high temperature combine to require a MOSFET pre-driver that is able to deliver large MOSFET gate drive and switching capabilities and the device is adopted in systems, which use sinusoidal control of the motor phase currents and this commutation method provides smooth operation, which reduces audible noise and minimizes torque ripple at the load.

Key features of A4933 include:
An integrated charge pump provides full gate drive for battery voltages (Vbb) down to 7 Vand reduced gate drive battery voltages as low as 5.5 V,
A top-off charge pump (TOCP) that enables 100% pulse-width-modulation (PWM),
An adjustable dead-time that can be regulated by the user,
Adjustable drain-to-source monitor (VDSTH),
Improved fault diagnostics that enhances the user's ability to decode and identify faults.

Availability and package:
The A4933KJPTR-T is available in a 48L eLQFP small profile, thermally efficient package with exposed pad.