What is an AC Adapter?
An AC adapter is an external power source that changes the direct current (DC) required by an electronic device from the alternating current (AC) supplied by a wall outlet. So, it is also called a charger or an AC/DC converter. AC adapters are used with equipment that needs a reasonably consistent voltage to convert higher voltage alternating current to lower direct voltage current. It is an extra power source for gadgets that are battery-operated or have no other power source. It is also correct to call it a charge when it gives power to battery-operated devices.

An AC adapter is composed of a central unit powered by an AC outlet. The computer uses DC power, which is converted by the device, and a second cord plugs into the device. AC adapters are necessary for electrical gadgets like laptops and cell phones because the direct current is also needed to recharge batteries. Older AC adapters waste a lot of electricity as standby power; however, more current legislation and related advancements have significantly decreased this waste. By eliminating the necessity for a power supply of a specified size, AC adapters make laptop computers smaller.
If a device doesn't have its power source, it must utilize an AC adapter to connect to the building's electricity mains. An adapter is needed when using a power source, such as a gaming system's power cord or a cell phone charger. Adapters are a sort of power supply. The power supply, which transforms AC power into the right kind of power for the device, is the big block that plugs into the wall. This converter is also known as a plug pack or a wall wart.
How does an AC Adapter work?
A transformer, a rectifier, and an electronic filter make up a basic AC adaptor. The transformer initially reduces an electrical outlet's relatively high voltage alternating current to a lower voltage that is adequate for powering the appliance. Next, a rectifier changes the alternating current into a direct current. Three different rectifier unit types are frequently utilized for ac adapters.
- Half wave Rectifier
- Full wave Rectifier
- SMPS Rectifier
1. Half-wave rectifier:
The half-wave rectifier successfully restricts current flow in one direction by employing a diode. A pulsing direct current result from this. This results in a loss of energy that lowers the mean voltage of half-wave rectified power to that of full-wave rectified power since half of the current are blocked.

2. Full-wave rectifier:
The full-wave bridge rectifier is a popular variety of full-wave rectifiers. These rectifiers reverse the direction of the electric current instead of blocking it in one direction, producing an output of continuously pulsing direct current. Full-wave rectifiers come in many different varieties.

Smoothing:
The two rectifiers mentioned above still have a wide range of output voltage. The majority of direct current devices, however, need a constant voltage to function. It is accomplished with a capacitor or a smoothing circuit. At the rectifier's output, a circuit component known as a smoothing capacitor is situated. When the rectifier does not produce any voltage, it releases stored energy. A reasonably constant voltage results from this. However, certain AC voltage ripples remain.

3. SMPS Rectifier(Modern AC adapter rectifier):
Input filter and rectifier MOSFETs and other switching components make up an inverter, Transformer, Output filter, and rectifier Based on their circuit topology. A switching regulator is included in a switched-mode power supply (SMPS), also known as a switch or switch-mode power supply. The Switched Mode Power Supply is the adaptor that is most frequently used nowadays (SMPS). These offer definite advantages over linear controlled power sources but are significantly more sophisticated. The primary benefit of SMPS is that it offers DC supplies that can deliver more power for a given adapter's size, price, and weight.

Advantages of AC Adapter
It is common practice to utilize external AC adapters to power small or portable electronic equipment. The benefits comprise:
- Safety
- decrease of heat
- reducing electrical noise
- reduction in size and weight
- simple replacement
- Variability in configuration
- Inventory, distribution, and certification of products are all made simpler.
- A particular kind of adapter used for laptops and PCs generates constant voltage. Eliminators are a frequent name for these kinds of adapters.
Disadvantages of AC adapter
- Cost increases when special specifications are needed.
- The equipment and adaptor must be transported together.
- It is important to replace or fix each gadget when the power supply malfunctions.
- Power supply requirements require model management.
Applications of AC Adapter
- Battery Charger
- Laptops
- ESP( Electrostatic precipitator) power supplies.
- Vehicles
- LED lighting and other consumer electronics.