ACadapter

An AC adapter, also known as a power adapter or power supply, is an external power supply used to convert alternating current (AC) from a wall outlet into direct current (DC) required by electronic devices. These devices are common for laptops, mobile phones, routers, and many other consumer electronics. They are designed to be portable and replace the need for internal power supplies within the device itself.

The primary function of an AC adapter is voltage transformation and conversion. It typically contains a transformer to step down the mains voltage to a lower, safer level, and a rectifier and filter circuit to convert the AC into DC. The output voltage and current are specific to the device it is intended to power, and using an adapter with incorrect specifications can damage the device.

AC adapters come in various shapes and sizes, with common connector types like barrel connectors, USB-A, USB-C, and proprietary connectors. The rating of an AC adapter is usually indicated in volts (V) for voltage and amperes (A) or milliamps (mA) for current. The combined power rating, measured in watts (W), is also important. Many modern AC adapters are "universal" and can operate across a range of input voltages, making them suitable for international travel. They are an essential component for the operation and charging of a vast array of electronic gadgets.