He uses them every day on his laptop; you use them on your mobile phone and even on your printer and other network devices. But what exactly are they and why do you need them?
Why can’t I just plug my laptop directly into the power outlet? Why does he have to have this extra device that I keep dragging around with him? If you’ve asked these questions, you probably don’t really understand the importance of AC adapters.
An AC adapter, simply put, is a type of power supply. It is a device that provides power to another device, yes, but why the redundancy?
Your DC device, your laptop, your cell phone, needs an AC adapter because it runs on direct current. Think of DC as a different “kind” of electricity. DC is generally associated with low voltage devices. Remember, the electricity in your home is 120 volts AC (if you live in the US and most other countries). Your microwave oven, television, and air conditioner need 120 volts to operate. Your laptop only needs 20 volts or less.
In this sense, an AC adapter is a power source that converts one form of electricity into another. Therefore, we can safely say that it is also a power converter.
DC devices, or things that run on direct current, are usually those that use batteries as their power source (batteries provide electricity in the form of DC). Because DC devices can work independently with the use of batteries, it is the electricity choice for mobile applications, even your car is DC powered.
Also, due to the nature of DC (current only runs in one direction), a low-voltage DC device can have a battery, charge it, and provide power to the device in a single circuit (starting from the adapter). So in this sense, an AC adapter is also a charger.
Other adapters take advantage of the fact that they are first in the circuit by providing some form of surge protection. If something unexpected happens to your AC electricity, the adapter shuts off the power before it destroys your precious device, which means they can also double as surge protectors.
So there you have it. An AC adapter is many things: a power supply, a power converter, and it can also be a charger and a surge protector. That is so important. So, don’t take your adapter for granted because your device relies heavily on it.