Current Regulators

A current regulators, or current source, is a device that can supply a constant current without the associated voltage across its terminals having an impact. All current regulators are non-ideal, meaning they have limitations under which they must be operated. This can be a limitation in the current range it can provide, and the load, or resistance, which can be driven by that said current.
A regulators can either be classified as an independent or a dependent regulators. Independent current sources will provide a predetermined amount of current without the influence of any outside factors (within specifications of the device). Dependent current sources are designed to change the current based on an external factor, often the voltage or current at another location of the device through a feedback mechanism.
Constant current sources are important to have in certain applications. Operational amplifiers have a version of a current regulators called a current mirror. These devices are ubiquitous across the electronics world, as voltage amplification is necessary in the majority of applications. They are also used as protective elements, when the devices downstream would be damaged by a current that was too high. Read more Read less