Alimentation à découpage (SMPS), also known as switch mode power supply or switch converter, is a high-frequency electrical energy conversion device and a type of power supply. Its function is to convert a precise voltage into the voltage or current required by the user through different forms of architecture. The input of a switching power supply is mostly an AC power supply (such as mains power) or a DC power supply, while the output is mostly a device that requires a DC power supply, comme un ordinateur personnel, et l'alimentation à découpage convertit la tension et le courant entre les deux.