If you were one of those curious students during your electronics classes’ days, you will remember the transistor and its capability to regulate currents and voltages. But remembering those transistor operation principles is not necessary to understand why a maintained voltage regulator of your car’s alternator or computer power supply is important. It would be good enough to remember that the proper regulation of the voltage in the chargers that we use everyday on our electronic gadgets and appliances will avoid defects.
How it Works
Voltage regulator is a part of almost any power supply system that operates on DC voltage. The alternator of our car is a good example. Inside it, the generated AC voltage is converted to DC voltage (via the AC to DC Conversion process) which in turn will be supplied to the SLI battery. Now, the battery is not designed to accept DC voltage that is higher or lower than 12 volts (It is important to note that other SLI battery charging system operates on 13.8V, 14.5V and 16V). What the voltage regulator does is that it maintains the output DC voltage of the alternator to a constant 12 volts.
Image Source: Electronics Project Circuits Website
From the above basic circuit diagram, you can see that from 12-14V input, the output is regulated to stable 12V. This system uses a transistor. The car’s alternator (as shown below) has a voltage regulator circuit system designed to output 12V, assembled to fit with the mechanical system, and withstand the environmental situation of the engine.
Image Source: Auto Shop 101 Website
Common Applications
There are different types and constructions of voltage regulators depending on the application. The most common application of a voltage regulator is on battery charging systems. These are the chargers that we use everyday for our mobile phones, laptops and other portable devices that rely on battery power. One excellent type of rechargeable battery of vast applications is the SLI battery. We will discuss the ways of charging it in the next post.
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