The present invention relates to an electronic device for a motor, the motor is used for driving a display device, the electronic device comprises a computing unit capable of generating a signal for representing a practical intensity, the motor comprises a rotor in a magnetic circuit, a positive terminal and a negative terminal, the computing unit controls the motor through the two terminals, the electronic device further comprises at least one shock detection circuit connected between the computing unit and the motor terminals and used for detecting an external shock applied to the motor, the motor has a first stable equilibrium position arranged at a reference angular position and a second stable equilibrium position arranged 180 degrees from a first stable angular position, and a maximum angular position for each rotation direction, and the motor rotor is no longer possible to return to an anterior angular position from the maximum angular position. The computing unit can detect the rotation direction of the rotor by analyzing an induction voltage detected by the detection circuit after the shock by employing the algorithm and cause a blocking pulse having an inverse sending polarity of that of induction voltage.