Constant current

A constant current (steady current, time-independent current, stationary current) is a type of Direct Current (DC) that does not change its intensity with time.

If the load is constant, a steady current can be obtained via a constant voltage source. If the load is varying, a steady current can be obtained via a constant current supply source.

An electrochemical cell is a device capable of either generating electrical energy from chemical reactions or facilitating chemical reactions through the introduction of electrical energy. A common example of an electrochemical cell is a standard 1.5-volt cell meant for consumer use. This type of device is known as a single Galvanic cell, so an obsolete name for steady current was galvanic current. A battery consists of two or more cells, connected in either parallel or series pattern.

A homopolar generator is an electrical generator comprising an electrically conductive disc or cylinder rotating in a plane perpendicular to a uniform static magnetic field. A magnetohydrodynamic generator directly extracts electric power from moving hot gases through a magnetic field, without the use of rotating electromagnetic machinery.

AC generators can be used as sources of steady current with a rectifier and a good ripple filter. Pulsed DC generators can be used as sources of steady current with a good ripple filter.

In electronics, a constant current system is one that varies the voltage across a load to maintain a constant electric current. When a component is indicated to be driven by a constant current, the driver circuit is, in essence, a current regulator and must appear to the component as a current source of suitable reliability.

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