In a feedback control mechanism for active damping of slider air bearing
vibrations in a hard disk drive slider, a filter is used to filter a
velocity signal from a slider to acquire a vibration signal. A
phase-shifter, electrically coupled with the filter, shifts the phase of
the vibration signal. An amplifier, electrically coupled with the
phase-shifter, adjusts the amplitude of the phase-shifted vibration
signal to achieve an amplitude adjusted vibration signal. An electrical
coupler couples the amplitude adjusted vibration signal to the slider for
actively damping air bearing vibrations in the slider.