A haptic engine includes a gap-closing actuator having a double-wound driving coil in which the two windings can be activated with two driving sources, respectively. Or, the two windings double-wound driving coil can be activated with a single driving source when the two windings are connected with each other either in series or in parallel. By using the double-wound driving coil in the gap-closing actuator as described, an instant inductance of either of the two windings can be determined without having to measure in real time a resistance of the corresponding winding.

A haptic engine includes a linear resonant actuator having a double-wound driving coil which is used for sensing a back electromotive force (EMF) voltage independently of the coil resistance, thus minimizing the back EMF voltage's sensitivity to temperature.

Provided are an automatic advance angle control system and method for a brushless linear direct current (BLDC) motor. The automatic advance angle control system for the BLDC motor includes a current controller configured to generate an anti-windup output for compensating for accumulated errors of an output voltage provided to the BLDC motor; a voltage headroom calculator configured to generate a voltage headroom from a counter-electromotive force and the output voltage provided to the BLDC motor; and an advance angle controller configured to generate an advance angle for controlling a phase of a phase current of the BLDC motor by performing proportional integration on a difference between the anti-windup output and the voltage headroom when the anti-windup output is generated and configured to ignore the generation of the advance angle when the anti-windup output is not generated.

Provided are an automatic advance angle control system and method for a brushless linear direct current (BLDC) motor. The automatic advance angle control system for the BLDC motor includes a current controller configured to generate an anti-windup output for compensating for accumulated errors of an output voltage provided to the BLDC motor; a voltage headroom calculator configured to generate a voltage headroom from a counter-electromotive force and the output voltage provided to the BLDC motor; and an advance angle controller configured to generate an advance angle for controlling a phase of a phase current of the BLDC motor by performing proportional integration on a difference between the anti-windup output and the voltage headroom when the anti-windup output is generated and configured to ignore the generation of the advance angle when the anti-windup output is not generated.

A linear drive mechanism which moves a detector having sensitivity in a first axial direction, relatively to a workpiece in a second axial direction orthogonal to the first axial direction, the linear drive mechanism includes: a drive shaft extending in the second axial direction; a mover which is supported in a non-contact fashion by the drive shaft and configured to move along the drive shaft integrally with the detector or the workpiece; a guide provided at a position deviated relative to the drive shaft in a third axial direction orthogonal to both the first axial direction and the second axial direction, the guide parallel to the drive shaft; and a resistance force generator which is provided on one of the mover and the guide, and is in contact with the other of the mover and the guide, the resistance force generator generates a resistance force which resists against movement of the mover.

A camera module actuator includes, a magnet, a coil, a driver, and a position estimating processor. The coil is disposed to face the magnet. The driver is configured to move the magnet by applying a driving signal to the coil. The position estimating processor is configured to estimate a position of the magnet from an oscillating signal. A frequency of the oscillating signal varies according to a movement of the magnet.

A camera module actuator includes, a magnet, a coil, a driver, and a position estimating processor. The coil is disposed to face the magnet. The driver is configured to move the magnet by applying a driving signal to the coil. The position estimating processor is configured to estimate a position of the magnet from an oscillating signal. A frequency of the oscillating signal varies according to a movement of the magnet.

A ringing peak detector circuit includes an input buffer receives a pair of differential feedback signals indicating a drain-source voltage of the at least one low side electronic switch. The input buffer generates shifted differential feedback signals having a common mode voltage that is equal to approximately one half of the supply voltage. A peak detector circuit is coupled to the input buffer to receive the shifted differential voltage signals. The peak detector circuit detects a peak value of an oscillation on the inductive electric load and to generate an output signal indicating the detected peak value. A circuit generates a control signal based on the detected peak value and a maximum value, with the control signal being applied to the inductive electrical load driver to control switching of the at least one low side switch.

A ringing peak detector circuit includes an input buffer receives a pair of differential feedback signals indicating a drain-source voltage of the at least one low side electronic switch. The input buffer generates shifted differential feedback signals having a common mode voltage that is equal to approximately one half of the supply voltage. A peak detector circuit is coupled to the input buffer to receive the shifted differential voltage signals. The peak detector circuit detects a peak value of an oscillation on the inductive electric load and to generate an output signal indicating the detected peak value. A circuit generates a control signal based on the detected peak value and a maximum value, with the control signal being applied to the inductive electrical load driver to control switching of the at least one low side switch.

A control device for a linear motor includes a speed controller that calculates a current command value by an integration operation using a first integral value of a difference between a moving speed of a movable element provided in the linear motor and a speed command value calculated on the basis of a position command value, a current controller that applies a voltage to the linear motor on the basis of the current command value, and a correction value storage unit that stores the first integral value of the speed controller when the movable element remains at a position indicated by the position command value. When resuming control of the linear motor, the speed controller sets the first integral value stored in the correction value storage unit as an initial value for the integration operation before the brake controller turns off the brake device.