A buck regulator for converting an input DC voltage, V+, into an output DC voltage level includes a coupled inductor for outputting the DC voltage level, and an error amplifier for sensing an error in the outputted DC voltage level and a pulse width modulator providing a pulse waveform having a duty cycle responsive to the error. The sheath slides lengthways along the handle alternating between a blocking position in which the sheath covers the blade, and a ready position in which the blade is exposed and the sheath forms part of the grip. The silicon substrate can include at least one doped region a dielectric layer formed over the doped region. The plural lamp connectors are serially connected with each other, and have respective positive terminals and respective negative terminals connected with corresponding lamps, thereby outputting respective output voltages and respective output currents to corresponding lamps.