The present disclosure provides a feedback control system and method for a bidirectional VCM. The system employs an analog core that is common to both the PWM and linear modes of operation. The analog core includes a feedback mechanism that determines the error in the current flowing through the motor. The feedback mechanism produces an error voltage that corresponds to the current error, and applies the voltage to a control driver. The control driver then controls the motor, based on the error voltage, in either a PWM or linear mode. By sharing a common core, the switching time between modes is improved. Furthermore, the output current error between modes is reduced.

The present disclosure provides a feedback control system and method for a bidirectional VCM. The system employs an analog core that is common to both the PWM and linear modes of operation. The analog core includes a feedback mechanism that determines the error in the current flowing through the motor. The feedback mechanism produces an error voltage that corresponds to the current error, and applies the voltage to a control driver. The control driver then controls the motor, based on the error voltage, in either a PWM or linear mode. By sharing a common core, the switching time between modes is improved. Furthermore, the output current error between modes is reduced.

Some embodiments include a camera voice coil motor (VCM) actuator configured to shift a lens and/or an image sensor along multiple axes. The VCM actuator may include a bottom flexure and a top flexure that connect one or more dynamic members to one or more static members. The VCM actuator may include stationary magnets and coils held by dynamic members. In some cases, the VCM actuator may be configured to move the image sensor along an optical axis, to move the image sensor in directions orthogonal to the optical axis, and/or to tilt the image sensor relative to the orthogonal axis. In some examples, the VCM actuator may be configured to move the image sensor in directions orthogonal to the optical axis, to move the lens along the optical axis, and/or to tilt the lens relative to the optical axis.

Some embodiments include a camera voice coil motor (VCM) actuator configured to shift a lens and/or an image sensor along multiple axes. The VCM actuator may include a bottom flexure and a top flexure that connect one or more dynamic members to one or more static members. The VCM actuator may include stationary magnets and coils held by dynamic members. In some cases, the VCM actuator may be configured to move the image sensor along an optical axis, to move the image sensor in directions orthogonal to the optical axis, and/or to tilt the image sensor relative to the orthogonal axis. In some examples, the VCM actuator may be configured to move the image sensor in directions orthogonal to the optical axis, to move the lens along the optical axis, and/or to tilt the lens relative to the optical axis.

A method for operating a magnetic actuator comprises: ascertaining a mathematical model of the actuator which describes a change in a motor constant of the actuator as a function of the electrical drive power supplied; driving the actuator with a first electrical drive power as a function of a predetermined target force; ascertaining the change in the motor constant of the actuator on account of driving the actuator with the first electrical drive power via the mathematical model; ascertaining a correction value for the first electrical drive power as a function of the ascertained change in the motor constant; and driving the actuator with a second electrical drive power as a function of the first electrical drive power and the ascertained correction value.

A method for estimating actuator parameters for an actuator, in-situ and in real-time, may include driving the actuator with a test signal imperceptible to a user of a device comprising the actuator during real-time operation of the device, measuring a voltage and a current associated with the actuator and caused by the test signal, determining one or more parameters of the actuator based on the voltage and the current, determining an actuator type of the actuator based on the one or more parameters, and controlling a playback signal to the actuator based on the actuator type.

Certain aspects of the present disclosure generally relate to methods and apparatus for driving haptic actuators. An example actuator driver circuit generally includes a driver and calibration circuitry. The driver has at least one output for coupling to at least one input of an actuator. The calibration circuitry is configured to: detect a phase of a voltage signal at the at least one output of the driver, detect a phase of a current signal at the at least one output of the driver, determine a phase difference between the phase of the voltage signal and the phase of the current signal, and adjust a frequency of an oscillating signal for the driver, based at least in part on the phase difference.

Certain aspects of the present disclosure generally relate to methods and apparatus for driving haptic actuators. An example actuator driver circuit generally includes a driver and calibration circuitry. The driver has at least one output for coupling to at least one input of an actuator. The calibration circuitry is configured to: detect a phase of a voltage signal at the at least one output of the driver, detect a phase of a current signal at the at least one output of the driver, determine a phase difference between the phase of the voltage signal and the phase of the current signal, and adjust a frequency of an oscillating signal for the driver, based at least in part on the phase difference.

A haptic system includes a haptic engine in which a reluctance motor is driven by a driver controller operated in conjunction with an impedance-estimator that uses amplitude-modulated calibration signals. An enveloped-calibration signal is superimposed on a haptic-drive signal to quickly, and accurately, estimate the driving coil's impedance, while minimizing power penalty.

A voice coil motor driving device and a method for providing control signals of the same are provided. The voice coil motor driving device includes a control module, a current driving module, and an input module. The current driving module outputs a plurality of digital current signals according to a driving signal, each of the plurality of digital current signals includes a plurality of current unit signals, and each of the plurality of digital current signals is arranged in a first time period, each of the plurality of digital current signals includes a plurality of reverse current unit signals, and the plurality of reverse current unit signals are arranged in a second time period, which is at a beginning of the first time period, or arranged in a third time period, which is at the end of the first time period.