Abstract: An actuator of a camera module including a magnet, a driving coil facing the magnet, a driving apparatus including a driving circuit configured to apply a driving signal to the driving coil to move the magnet, and a position calculator configured to generate a feedback signal based on a current position of the magnet, wherein the driving apparatus is further configured to calculate an error value by comparing an input signal with the feedback signal, and to determine a control gain of a control signal provided to the driving circuit according to the error value, and wherein the control gain is reduced in response to an increase in the error value, and the control gain is increased in response to a decrease in the error value.

Abstract: An actuator of a camera module including a magnet, a driving coil facing the magnet, a driving apparatus including a driving circuit configured to apply a driving signal to the driving coil to move the magnet, and a position calculator configured to generate a feedback signal based on a current position of the magnet, wherein the driving apparatus is further configured to calculate an error value by comparing an input signal with the feedback signal, and to determine a control gain of a control signal provided to the driving circuit according to the error value, and wherein the control gain is reduced in response to an increase in the error value, and the control gain is increased in response to a decrease in the error value.

Abstract: An actuator includes a magnet, a driving coil, a driver, and a position detector. The magnet is disposed on one surface of a lens barrel. The driving coil is disposed at a proximity of the magnet. The driver is configured to apply a driving signal to the driving coil to move the lens barrel along an optical axis. The position detector is configured to generate an oscillation signal of which a frequency is changed based on movement of the magnet and configured to compare oscillation signals generated in a first position and a second position of the lens barrel to detect a present position of the lens barrel.

Abstract: A digital frequency measuring apparatus includes a frequency divider dividing an input frequency signal and providing a divided frequency signal; a period counter counting clock cycles in a period of the divided frequency signal using a clock signal and providing a period count value for each period; and a digital filter amplifying the period count value using an accumulated gain, converting an amplified period count value into a frequency, and providing a first digital output value. The digital filter determines the accumulated gain using a predetermined stage number and a predetermined decimator factor.