Switched-mode power supply
A switched-mode power supply (SMPS), also called switching-mode power supply, switch-mode power supply, switched power supply, or simply switcher, is an electronic power supply that incorporates a switching regulator to convert electrical power efficiently.
An adjustable switched-mode power supply for laboratory use
This charger for a small device such as a mobile phone is an off-line switching power supply with a European plug, mainly consisting of an opto-coupler, a rectifier and two active components.
Zero voltage switched mode power supplies require only small heatsinks as little energy is lost as heat. This allows them to be small. This ZVS can deliver more than 1 kilowatt. Transformer is not shown.
Switched mode mobile phone charger
A power supply is an electrical device that supplies electric power to an electrical load. The main purpose of a power supply is to convert electric current from a source to the correct voltage, current, and frequency to power the load. As a result, power supplies are sometimes referred to as electric power converters. Some power supplies are separate standalone pieces of equipment, while others are built into the load appliances that they power. Examples of the latter include power supplies found in desktop computers and consumer electronics devices. Other functions that power supplies may perform include limiting the current drawn by the load to safe levels, shutting off the current in the event of an electrical fault, power conditioning to prevent electronic noise or voltage surges on the input from reaching the load, power-factor correction, and storing energy so it can continue to power the load in the event of a temporary interruption in the source power.
A simple general-purpose desktop power supply used in electronic labs, with power output connector seen at lower-left and power input connector (not shown) located at the rear
Interior of high-end linear power supply with toroidal mains transformer.
A rackmount, adjustable regulated DC power supply
Electronic bench power supply unit with "banana connector" output