A D-sub connector is a type of electrical connector that is used mainly in computing. It is most commonly used for video connections, such as those between a monitor and computer. The D-sub connector uses a series of pins that slot into a socket, with the plug usually screwed into place to prevent it coming loose.
D-sub is short for D-subminiature. This form is no longer used, as these connectors are no longer considered miniature in computing terms; indeed they are among the largest plugs used in computing. The D does not stand for digital. Instead, it comes from the connector's creators, ITT Cannon, who used the D to indicate that the pins are housed in a D-shaped shell. This D is then followed by another letter denote the size of the plug and socket in terms of the capacity of pins that can be housed, then a number showing the number of pins used.
There are a wide range of past and present uses for D-sub connectors. These include printer cables, computer game joysticks and external floppy disk drives. They are also used in some multi-channel audio recording systems.
The most common use of the D-sub connector is as a video connector. This is in a plug and socket known as DE15, meaning it is D-shaped, size E in ITT Cannon's system, and has 15 pins. These are arranged in three rows of five.
The DE15 is better known as a VGA connector. It is for analog video connections between computers and monitors, but is also used on some television sets as a way to display a computer image. There is a mini version of this socket, which is used on some laptop computers.
The D-sub connector is becoming much less popular in general computing. This is partly because it is comparatively bulky and thus unsuitable for portable devices. It also requires some system for locking into place, usually through adjustable screws. This makes it more expensive than other plug types.
The specific use of a D-sub connector for monitors is also falling from favor. It is being replaced with the DVI and HDMI systems. HDMI has the advantage of being a simple flat plug with no pins. DVI is physically more similar to D-sub but is less bulky and has 24 pins. Both DVI and HDMI carry digital signals, which a D-sub connector cannot do. HDMI is also able to carry audio signals as well as video.