Sensorless three-phase motor controller for automotive BLDC implementation

June 20, 2016 // By Nick Flaherty
LV8907UW sensorless BLDC controller fro ON Semiconductor
ON Semiconductor has launched a new controller for sensorless, brushless DC motors in automotive applications.

The LV8907UW supports an operating voltage range from 5.5 to 20 volts (4.5 to 40 V transient) for streamlined solutions for driving three-phase brushless motors. The LV8907UW integrates gate drivers for six N-channel MOSFETs, and a dual-stage charge pump for 100% duty-cycle operation. In its lowest cost configuration the IC can operate without an external microcontroller. The device requires no programming, as key parameters and functions - such as startup and speed setting - can be configured via SPI interface and stored in embedded non-volatile (OTP) memory. Open-loop and closed-loop speed control are possible. For more complex applications the LV8907UW can also support a small microcontroller with its integrated linear regulator (3.3V or 5V, 50mA), a local interconnect network (LIN) transceiver for automotive connectivity, and a watchdog timer.

The parts are AEC-Q100 qualified with an operational temperature range up to 175°C, ensuring reliable operation in challenging automotive environments. Integrated protection mechanisms include over-current, over-voltage, short circuit, under-voltage, and over-temperature. The features of the device make it ideal for use in automotive water pumps, oil pumps, fuel pumps, HVAC systems, radiator fans, and headlamp cooling units.

“Compelled by market pressures and increasingly stringent legislative measures, automotive manufacturers need to find ways to improve the fuel economy of their models.  Electrification of former mechanical applications – such as pumps and fans – is a key step in this path”, explains Ikuya Kawasaki, General Manager of System Solutions Group at ON Semiconductor. “Thanks to its high degree of integration and support for sensor-less operation, the LV8907UW enables motor systems to attain maximum efficiency levels without a microcontroller. The resulting designs have reduced complexity and bill of materials, and enhanced reliability.”

The LV8907UW is supplied in a SQFP48K package format and available at $5.55 per unit in 2500 unit quantities.