Motor control device, and optical scanning device, image forming device and printed circuit board including the same

An optical scanning device comprising:

• a light source;
• a mirror configured to deflect light emitted from the light source;
• a motor configured to rotate the mirror;
• a first detector element configured to detect the light deflected by the mirror and to output a first detection signal;
• a second detector element configured to output a second detection signal by the motor rotating;
• and
• a rotation direction determination unit configured to determine a rotation direction of the motor in a state of the motor rotating at a speed lower than a target speed, wherein the rotation direction determination unit determines that the motor is undergoing a forward rotation when a time difference between an output timing of the first detection signal and an output timing of the second detection signal falls within a predetermined range, and determines that the motor is undergoing a reverse rotation when the time difference does not fall within the predetermined range.

An image forming device comprising:

• an image carrier;
• and
• an optical scanning device configured to form a latent image by irradiating the image carrier with light,
• wherein the optical scanning device includes:
• a light source;
• a mirror configured to deflect light output from the light source;
• a motor configured to rotate the mirror;
• a first detector element configured to detect the light deflected by the mirror and to output a first detection signal;
• a second detector element configured to output a second detection signal by the motor rotating;
• and
• a rotation direction determination unit configured to determine a rotation direction of the motor in a state of the motor rotating at a speed lower than a target speed, wherein the rotation direction determination unit determines that the motor is undergoing a forward rotation when a time difference between an output timing of the first detection signal and an output timing of the second detection signal falls within a predetermined range, and determines that the motor is undergoing a reverse rotation when the time difference does not fall within the predetermined range.

A printed circuit board comprising:

• a motor of which a rotation axis thereof is fixed at the printed circuit board;
• and
• a semiconductor integrated unit including a detector element and a control unit to control the motor in accordance with a signal from the detector element,
• wherein the detector element is configured to detect a position of a rotor of the motor, and
• wherein the semiconductor integrated unit is mounted obliquely with respect to the printed circuit board so that a distance from a center of a rotation shaft of the motor to the detector element is maintained at a predetermined distance.

A printed circuit board on which a motor is mounted, comprising:

• an integrated circuit (IC) including:
• a detector element configured to detect information concerning to a rotational position of the motor;
• and
• a drive circuit configured to drive the motor based on a detection result of the detector element;
• wherein the IC is mounted on the printed circuit board such that the detector element of the IC is located in a space between the motor and the printed circuit board.