Voltage regulator
Also: power converter
A circuit that maintains a target output voltage across an allowed input and load range.
Linear regulators dissipate voltage difference as heat; switching converters transfer energy through switched storage elements with finite efficiency and ripple.
Example A 5 V regulator supplies a processor from a battery whose voltage changes during discharge.
Common misconception A regulator's headline current is not guaranteed at every input voltage, temperature, or cooling condition.