Switch Mode Power Supply (SMPS), also known as switch mode power supply or switch converter, er hátíðni raforkubreytingartæki og tegund aflgjafa. Hlutverk þess er að umbreyta nákvæmri spennu í þá spennu eða straum sem notandinn þarfnast í gegnum mismunandi gerðir arkitektúrs. 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, such as a personal computer, and the switching power supply converts the voltage and current between the two.