When a BLDC motor is driven with a sine wave, changes in the RPM of a motor due to the effect of its impedance cause a phase difference between its voltage and current. This difference decreases drive efficiency. Because of this difference, a phase adjustment is necessary to improve efficiency. Intelligent Phase Control technology compares the relationship between the current phase (current information) and the voltage phase (Hall-effect signal). It then provides feedback to the motor current control signal to align the voltage and current phases automatically. As a result, Intelligent Phase Control technology provides high efficiency.