
3-phase gate driver for electric and hybrid vehicles
Allegro MicroSystems, a supplier of power electronics and sensing solutions for motion control and energy-efficient systems, has added the A89307 automotive-qualified gate driver IC to its QuietMotion range. Designed for battery fans and HVAC systems in electric and hybrid vehicles, the driver’s field-oriented control (FOC) ensures quiet operation and low vibration by providing a continuous sinusoidal current to the load. This helps automotive OEMs reduce noise and extend battery/battery life to achieve more kilometres per battery charge and reduce the vehicle’s carbon footprint.
Electric and hybrid vehicles are inherently quieter than conventional internal combustion engine models – especially when stationary – and drivers are increasingly sensitive to noise generated by components such as cooling fans. The A89307’s hardware-based algorithm makes it easier for designers to dampen fan noise while improving cooling performance and increasing miles per battery charge, the manufacturer promises.
The A89307 contains a hardware-based algorithm that requires no external sensors or software development. Users simply select the parameters via a GUI interface and load them into the IC’s on-chip EEPROM. With only five external components, the A89307 helps reduce material costs by shrinking the bill of materials and enabling low PCB space requirements in the motor. Its fully integrated algorithm can even eliminate the need for a separate microprocessor.
Operating modes include open-loop PWM or fully programmable closed-loop speed control. In closed-loop mode, the PWM speed relationship can be programmed to match PWM commands from an external ECU. Field weakening is provided to improve performance at high speeds. Low speed operation and windmilling startup are just some of the features included in the A89307’s hardware-based digital algorithm.
While designed for xEV battery fans, the A89307 can also be used in HVAC blowers and liquid pumps in traction inverter cooling systems. The external gate drive makes the device flexible enough to drive a wide range of motors up to 500W.
