Patent ID: 8508182

Claim:
A system comprising: an alternating current-to-direct current (AC-to-DC) power supply having a first stage providing a first DC voltage and a second stage providing a second DC voltage, the second DC voltage less than the first DC voltage; and, a blower electrically connected to the first stage of the AC-to-DC power supply to receive the first DC voltage from the AC-to-DC power supply to power the blower, wherein the first stage is to be directly connected to an AC signal and is to convert an AC voltage of the AC signal to the first DC voltage, wherein the second stage is directly connected to the first stage, is not to be directly connected to the AC signal, and is to convert the first DC voltage to the second DC voltage, wherein the AC-to-DC power supply has a first power-conversion efficiency at the first stage and a second power-conversion efficiency at the second stage, the second power-conversion efficiency less than the first power-conversion efficiency, such that electrical connection of the blower to the first stage of the AC-to-DC power supply instead of to the second stage of the AC-to-DC power supply wastes less power and is more efficient, wherein the first power-conversion efficiency is defined as a first stage output power that is output by the first stage divided by an input power that is input to the first stage from the AC signal, and wherein the second power-conversion efficiency is defined as a second stage output power that is output by the second stage divided by the input power that is input to the first stage from the AC signal.