Voltage Regulators

Voltage regulators are components that maintain a consistent voltage output. Electronic components are often made to accept only a low maximum voltage, and can be badly damaged by a power surge. Likewise, a low voltage can fail to provide enough power for the component. Voltage regulators are often responsible for maintaining a voltage within the range that the electronic component can safely accept.

A computer is one example of an electronic device that requires voltage regulators. Voltage regulators are responsible for transmitting the voltage generated by the computer's power supply in a low-voltage flow that won't damage the microprocessor. A computer may require one or two voltage regulators, depending on the system; some computers use special "voltage ID programmable" voltage regulators, which interface with the microprocessor to ensure a specific voltage level.

Cars also use voltage regulators in the system that maintains the battery's charge. Voltage regulators are usually part of the car's alternator, although many cars, particularly older cars and modern American models, have exterior voltage regulators. Alternators or generators are used to generate power, which is fed into the car's battery in order to maintain a full charge. The power generated by the car's charging system is also used to run the car's electrical systems, such as headlights, radio, power windows and locks, and ventilation systems.

An alternator or generator has a pulley on one side that is turned by one of the engine's drive belts; the force of the engine is therefore used to run the alternator or generator. Because the engine's speed varies during acceleration and shifting gears, voltage regulators are necessary to control the output produced by the alternator or generator. An excessively high voltage output, caused by the engine's higher speeds if the alternator or generator is unregulated, could send a surge through the system, overcharging the battery and damaging the car's electrical systems. A very low voltage output will fail to produce enough power to maintain the battery's charge and run the car's electronic systems, creating a load on the battery and potentially reducing the battery's life.

When voltage regulators stop working, they need to be replaced. Voltage regulators for computers or other basic household electronics are available through dealers that specialize in electronics. For cars, voltage regulators are available from the dealership or aftermarket parts stores. Some cars may have external voltage regulators, in which case the voltage regulator may be purchased separately and easily replaced. However, most cars' voltage regulators are located inside the alternator, requiring the owner to either buy a new alternator or rebuild the existing alternator with a new voltage regulator.