A biopsy device having a translating and rotating cutter is disclosed. The assembly includes a circuit board on which a plurality of bare power components is arranged. The compositions are useful in various surfactant applications. The power control interface can also use its energy storage capacity to provide voltage support at the point of injection into the power transmission system, as well as fault clearance capability for \u201criding out\u201d transient fault conditions occurring on the power transmission line.