A switched-mode power supply (switching-mode power supply, switch-mode power supply, SMPS, or switcher) is an electronic power supply that incorporates a switching regulator to convert electrical power efficiently. Like other power supplies, an SMPS transfers power from a source, like mains power, to a load, such as a personal computer, while converting voltage and current characteristics . A switch-mode power supply (switching-mode power supply, switch-mode power supply, SMPS, or switcher) include control logic and oscillator. SMPS is in different types for 1phase, 2 phase , 3 phase. special features of switched-mode power supply: – Short circuit protection – High efficiency – Parallel connection in order to get more output power.