Abstract: Described is an apparatus which comprises: a plurality of transistors coupled to an input power supply and to a load; a first comparator with a first node coupled to the load, and a second node coupled to a first reference; a second comparator with a first node coupled to the load, and a second node coupled to a second reference, the second reference being different from the first reference; and a logic unit to receive output of the first comparator and output of the second comparator, the logic unit to turn on or off transistors of the plurality of transistors according to outputs of the first and second comparators.

Abstract: The present invention provides a method for soldering components to a printed wiring board. In one embodiment, the method comprises applying a substantially lead-free solder to the printed wiring board, placing an electronic component having lead-free terminals on the solder, and heating the printed wiring board in a substantially oxygen-free atmosphere to a temperature sufficient to reflow the solder. In an alternative embodiment, the method may further comprise applying a tin-based solder. In a particularly advantageous embodiment, the method includes applying a solder alloy of tin and a metal selected from the group consisting of: silver, antimony, copper, and gold.