A voltage regulator is an electromechanical component used to maintain a steady output of volts in a circuit. It does this by generating a precise output voltage of a preset magnitude that stays constant despite changes to its load conditions or input voltage. The two types of voltage regulators are switching and linear.

Electric components are built to receive a specified amount of volts and can be seriously damaged if the power surges, and low voltages may not be able to power up a component to its full functionality. Regulators ensure the voltage is within a range the electric components can safely receive and use to optimally function. Depending on its design, a regulator can regulate single or multiple DC or AC voltages.