Toshiba's BLDC motor driver has vector control and sine wave output

The new TC7600FNG three-phase sine wave sensorless vector controller will help designers to lower the component count, reduce the noise and improve the efficiency of three-phase PWM BLDC motors in applications ranging from home appliances and pumps to industrial automation and automotive motor control. The device can be used in conjunction with a host microcontroller or as a stand-alone motor control solution depending on specific application requirements.

Toshiba’s new device is supplied in a compact SSOP30 package and integrates commutation logic, a vector computer, analogue-to-digital conversion circuitry, interfaces for three external shunts, a system clock generator, an internal reference power voltage and connections to a host microcontroller. The controller provides accurate closed loop speed control in both directions of rotation while eliminating the need for sensors and software programming.

In operation the TC7600FNG outputs a complete full-wave sine wave PWM drive without the need for additional processing. Sinusoidal current waveforms provide for smoother BLDC motor operation when switching between positive and negative polarities in the driver circuit. This ensures lower electrical and acoustic noise and less vibration than conventional PWM outputs, while still allowing designers to realise the full benefit of PWM efficiency.

The TC7600FNG operates from a supply voltage of 4.5V to 5.5V and incorporates lead angle control and selectable dead time settings (from 0 to 2µs). These features allow the designer to optimise efficiency by tuning the delay between current and voltage phases and ensure safe operation of power FETs in a push-pull configuration.