When it comes to laptop AC adapters, there are a wide variety of connectors that connect the adapter to the laptop’s power supply. Manufacturers specifically try to make their adapter unique for each model, and even compared to other manufacturers, to avoid a user plugging an adapter into the wrong machine, which could cause damage. Here we will look at a few of the most common types of connectors.
Barrel Connectors
Most modern laptop AC adapters use a “barrel” type of connector. It consists of a cylindrical shaft that is hollow inside. When the barrel is connected, a pin (tip) goes inside the barrel, and the outer portion of the barrel makes contact with a different part of the power supply. The tip usually carries the positive pole while the barrel carries the negative pole. Barrel connectors come in a wide variety of sizes to avoid confusion between different manufacturers and models. For example, HP laptop parts often use a different pin and barrel size than another manufacturer such as Acer.
3-Pin and 4-Pin Connectors
Some laptops and AC adapters use a 3-pin or 4-pin type of connector, also referred to as a “Snap and Lock” type. These connectors use a large cylindrical connector with 3 or 4 pins inside. Snap and lock connectors are particularly useful in laptops that are designed for durability, as they are very stable and secure, and not prone to breakage.
Oval Connectors
Oval connectors are similar to barrel connectors, but utilize and oval shape to prevent connecting them to standard barrel connections, since connecting an adapter to the wrong laptop could cause damage to the system board or other components, requiring a costly laptop repair. They are not used frequently.
Octagon Connectors
Octagon connectors are similar to snap and lock connectors, but they utilize 8 pins that give even more stability and a more solid connection.