Allegro MicroSystems has announced a new full-bridge controller for use with N-channel external power MOSFETs that has been specifically designed for automotive applications. Allegro's A5929 has a unique charge pump regulator that provides full (>10 V) gate drive at battery voltages down to 7 V and allows the device to operate with reduced gate drive at battery voltages down to 5.5 V. A bootstrap capacitor is used to provide the above battery supply voltage required for N-channel MOSFETs.
One logic level input is provided for each of the four power MOSFETs in the full-bridge, allowing motors to be driven with any PWM 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.
The A5929KLPTR-T is supplied in a 24-pin TSSOP power package with an exposed thermal pad (package type LP) for enhanced power dissipation. This package is available in lead (Pb) free versions, with 100% matte-tin lead frame plating (suffix ). It is priced at $1.60 in quantities of 1,000.