Abstract: A method and apparatus for automatic resonance detection is disclosed for a motor-driven mechanical system such as a voice coil motor (VCM) in which a resonance detector and driver are provided. The automatic resonance detector is implemented on the same integrated circuit as the driver, and dynamically determines the natural resonant frequency of the VCM driven by the driver. The resonant frequency is determined by measuring the back electromotive force (BEMF) of the VCM, detecting the slope of the BEMF signal, and determining the resonant frequency from the slope of the BEMF signal.

Abstract: An apparatus and method for determining characterizing attributes of an actuator is provided. An actuator may be moved to a maximum capacitance position. At the maximum capacitance position, an initial measurement of the actuator capacitance is made. The actuator is moved a predetermined increment toward a first extreme position, and the actuator capacitance is again measured. If the capacitance changed by a threshold amount, the signal preceding the signal that caused the actuator to move is recorded as an approximate response curve end point, or the first extreme position. The actuator is again moved a predetermined increment toward a second extreme position. After each move, the capacitance is measured. If it is determined the capacitance did change by a threshold amount from the previously measured capacitance, the signal related to the previously measured capacitance is recorded as an approximate response curve end point, or the second extreme position.

Abstract: A method and apparatus for automatic resonance detection is disclosed for a motor-driven mechanical system such as a voice coil motor (VCM) in which a resonance detector and driver are provided. The automatic resonance detector may be implemented on the same integrated circuit as the driver, and dynamically determines the natural resonant frequency of the VCM driven by the driver. The resonant frequency is determined by measuring the back electromotive force (BEMF) of the VCM, detecting the slope of the BEMF signal, and determining the resonant frequency from the slope of the BEMF signal.

Abstract: An apparatus and method for determining characterizing attributes of an actuator is provided. An actuator may be moved to a maximum capacitance position. At the maximum capacitance position, an initial measurement of the actuator capacitance is made. The actuator is moved a predetermined increment toward a first extreme position, and the actuator capacitance is again measured. If the capacitance changed by a threshold amount, the signal preceding the signal that caused the actuator to move is recorded as an approximate response curve end point, or the first extreme position. The actuator is again moved a predetermined increment toward a second extreme position. After each move, the capacitance is measured. If it is determined the capacitance did change by a threshold amount from the previously measured capacitance, the signal related to the previously measured capacitance is recorded as an approximate response curve end point, or the second extreme position.

Abstract: An apparatus and method for determining characterizing attributes of an actuator is provided. An actuator may be moved to a maximum capacitance position. At the maximum capacitance position, an initial measurement of the actuator capacitance is made. The actuator is moved a predetermined increment toward a first extreme position, and the actuator capacitance is again measured. If the capacitance changed by a threshold amount, the signal preceding the signal that caused the actuator to move is recorded as an approximate response curve end point, or the first extreme position. The actuator is again moved a predetermined increment toward a second extreme position. After each move, the capacitance is measured. If it is determined the capacitance did change by a threshold amount from the previously measured capacitance, the signal related to the previously measured capacitance is recorded as an approximate response curve end point, or the second extreme position.

Abstract: Embodiments of the present invention provide improved accuracy of displacement control by using a multi-segment transformation of an actuator's non-linear response. The present invention may set intermediate points to effectively divide the actuator response into multiple segments. Each segment may be assigned a transform function that represents the actuator's response in that particular segment. The present invention may operate in two modes, a calibration mode and a normal operations mode. During calibration mode, the intermediate points and the segment transforms may be set. During normal operations mode, a drive signal may be generated according to the calibrated set values.

Abstract: An apparatus, system and method for controlling drive patterns is disclosed. A digital engine for controlling drive patterns may include a profile controller to program characteristics of one or more drive patterns for one or more piezoelectric actuators. The digital engine may further include a register array to store profile information for the one or more drive patterns. Each drive pattern may comprise a plurality of pulses with each pulse having a slope. The digital engine may also include a digital pattern generator to generate the one or more drive patterns based upon the profile information stored in the register array. The digital engine may further include a slope shaping circuit to modify one or more signals based upon an input from the digital pattern generator.

Abstract: Embodiments of the present invention provide improved accuracy of displacement control by using a multi-segment transformation of an actuator's non-linear response. The present invention may set intermediate points to effectively divide the actuator response into multiple segments. Each segment may be assigned a transform function that represents the actuator's response in that particular segment. The present invention may operate in two modes, a calibration mode and a normal operations mode. During calibration mode, the intermediate points and the segment transforms may be set. During normal operations mode, a drive signal may be generated according to the calibrated set values.

Abstract: An apparatus and method for determining characterizing attributes of an actuator is provided. An actuator may be moved to a maximum capacitance position. At the maximum capacitance position, an initial measurement of the actuator capacitance is made. The actuator is moved a predetermined increment toward a first extreme position, and the actuator capacitance is again measured. If the capacitance changed by a threshold amount, the signal preceding the signal that caused the actuator to move is recorded as an approximate response curve end point, or the first extreme position. The actuator is again moved a predetermined increment toward a second extreme position. After each move, the capacitance is measured. If it is determined the capacitance did change by a threshold amount from the previously measured capacitance, the signal related to the previously measured capacitance is recorded as an approximate response curve end point, or the second extreme position.

Abstract: An apparatus, system and method for controlling drive patterns is disclosed. A digital engine for controlling drive patterns may include a profile controller to program characteristics of one or more drive patterns for one or more piezoelectric actuators. The digital engine may further include a register array to store profile information for the one or more drive patterns. Each drive pattern may comprise a plurality of pulses with each pulse having a slope. The digital engine may also include a digital pattern generator to generate the one or more drive patterns based upon the profile information stored in the register array. The digital engine may further include a slope shaping circuit to modify one or more signals based upon an input from the digital pattern generator.