Provided is a motor driving circuit which transmits a driving signal to a motor, including a gate driver generating the driving signal corresponding to a pulse width modulation signal, a pulse width modulation signal generator generating the pulse width modulation signal according to Hall sensor signals received from Hall sensors mounted in the motor, a current sensor measuring a link current provided to the gate driver, a low pass filter outputting a filter current that high frequency components are removed from the measured link current, and a minimum power consumption estimating unit generating a lead angle according to a start signal with reference to the filter current, wherein the pulse with modulating signal is changed according to the lead angle.