Allegro MicroSystems introduces new automotion-grade half-bridge MOSFET drivers

     Allegro MicroSystems announced the launch of two new N-channel power MOSFET driver ics capable of controlling MOSFETs connected in half-bridge configurations. Allegro's A4926 and A4927 are designed for automotive applications with high power inductive loads and are suitable for DC pumps (braking, oil, water and fuel), air conditioning systems (HVAC), solenoids and actuators. These devices are particularly suitable for automotive systems where ASIL requirements must be met, and like other products in the Allegro A2SIL™ family, the A4926 and A4927 are integrated with enough features to complement the system design and help users achieve the desired ASIL level requirements.

     The A4926 and A4927 have a unique integrated charge pump regulator that provides full door drive for most applications, even at battery voltages down to 5.5V. They come with a bootstrap capacitor with optional bootstrap management that can be used to provide the higher than battery supply voltage required for the n-channel MOSFETs. The half-bridge can be controlled by a separate logic level input or a SPI-compatible serial interface. External power MOSFETs are protected by programmable dead zones to avoid shoot-through.

     The A4926 and A4927 feature integrated diagnostics that provide multiple indications of internal, system, and power bridge failures, and can be configured to protect the power MOSFETs under most short-circuit conditions. In addition to providing full access to bridge control, the serial interface can also be used to change programmable Settings such as dead TIme, VDS threshold, gate drive current and fault blank TIme, through which detailed diagnostic information can be read. In addition, the A4927 includes an integrated low-side current amplifier with programmable gain and offset capabilities.