Power supplies

A switched-mode power supply (switching-mode power supply, switch-mode power supply, switched power supply, SMPS, or switcher) is an electronic power supply that incorporates a switching regulator to convert electrical power efficiently.

A solar cell, or photovoltaic cell (in very early days also termed "solar battery" – a denotation which nowadays has a totally different meaning, see here), is an electrical device that converts the energy of light directly into electricity by the photovoltaic effect, which is a physical and chemical phenomenon.

A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.

In electronics and electrical engineering, a fuse is a type of low resistance resistor that acts as a sacrificial device to provide overcurrent protection, of either the load or source circuit.

A power inverter, or inverter, is an electronic device or circuitry that changes direct current (DC) to alternating current (AC).

The Tesla coil is an electrical resonant transformer circuit designed by inventor Nikola Tesla around 1891 as a power supply for his "System of Electric Lighting".

In electricity generation, a generator is a device that converts mechanical energy to electrical energy for use in an external circuit.

An electric battery is a device consisting of one or more electrochemical cells with external connections provided to power electrical devices such as flashlights, smartphones, and electric cars.

The terms atomic battery, nuclear battery, tritium battery and radioisotope generator are used to describe a device which uses energy from the decay of a radioactive isotope to generate electricity.

A power supply unit (or PSU) converts mains AC to low-voltage regulated DC power for the internal components of a computer.

Power over Ethernet or PoE describes any of several standardized or ad-hoc systems which pass electric power along with data on twisted pair Ethernet cabling.

A watch battery or button cell is a small single cell battery shaped as a squat cylinder typically 5 to 25 mm in diameter and 1 to 6 mm high—like a button on a garment, hence the name.

A joule thief is a minimalist Armstrong self-oscillating voltage booster that is small, low-cost, and easy to build, typically used for driving small loads.

A DC-to-DC converter is an electronic circuit or electromechanical device that converts a source of direct current (DC) from one voltage level to another.

An analog signal to discrete time interval converter (ASDTIC) is a specialized kind of an analog-to-digital converter, which converts the analog input signal (e.g. voltage or current) to time intervals between pulses.

An AC adapter, AC/DC adapter, or AC/DC converter is a type of external power supply, often enclosed in a case similar to an AC plug.

A compensated pulsed alternator, also known by the portmanteau compulsator, is a form of power supply.