AS9120B, ISO 9001:2015, AND FAA AC 0056B ACCREDITED

What are D-Sub Connectors and Their Types?

Connectors are essential for most electrical devices and systems, serving to establish connections for the transfer of audiovisual and power signals alike. Depending on the application in question, one may take advantage of various electrical connector types, as each will tend to vary in its design, capability, and space restrictions. One common type of electrical connector is the D-sub type, that of which is known for its D-shaped metal shield that protects the contacts. D-sub connectors may be male or female, depending on whether they have pins or sockets. Nevertheless, the two types will always be designed in such a way that they can mate with one another to ensure signal transfer.

D-sub connectors trace back to their initial introduction in 1952, and the prefix “D” is used for the whole series of components while a letter such as A, B, C, D, or E will denote the size of the shell. After the shell size denotion, a number will be used to signify the amount of pins or sockets available, a P or S following that number for the gender of the connector. In most cases, the shell size can be used to determine the amount of pins or sockets, “A” connectors having 15, “B” connectors having 25, “C” connectors having 37, etc. With this basic system, one can understand that a DB-25 connector is a D-sub connector with a 25-position shell size and a 25-position contact design. While many connectors utilize the letter P or S to denote gender, some may use M for male and F for female instead.

For more compact applications that cannot take advantage of standard D-sub connectors, special connectors known as microminiature D (micro-D) and nanominiature D (nano-D) variations may be used. The micro-D connector is about half the length of a conventional D-sub connector, while the nano-D connector is about a quarter of the length of a standard D-sub connector. These connectors are regularly relied on for military and space-grade technology alike, often being available with MIL-SPEC specifications.

With their varying designs and layouts, there are a few applications that D-sub connectors regularly serve, including communication ports, network pots, computer video outputs, game controller ports, and more. The most common application is for RS-232 serial communications, such connectors being used for IBM and Macintosh computers alike. Additionally, a variety of uninterruptible power supply units utilize DE-9F connectors so that signals can be sent to a computer via an RS-232 interface. 

Many computers utilize D-cub connectors as well, using them for monitors to display a video output. While many modern systems now utilize HDMI connectors and technology, D-sub connectors are still common for MDA, Hercules, CGA, and EGA ports alike. If one has a D-sub connector port but wishes to use an HDMI connector for compatibility, a D-sub to HDMI adapter may be used.

If you are in the market for reliable D-sub connectors, connector cover components, and other such products, look no further than National Stock Number Parts. Owned and operated by ASAP Semiconductor, we present customers access to over 2 billion new, used, obsolete, and hard-to-find items that have been sourced from top global manufacturers that we like. Take the time to peruse our offerings as you see fit, and our online RFQ forms can help you secure competitive quotes for your comparisons with ease. With team members readily available for customers around the clock, we guarantee responses to quote requests within 15 minutes of receiving and reviewing a submitted form. If you have any questions or concerns regarding our offerings or services, give our team members a call or email at your earliest convenience, and we would be more than happy to assist you however we can! 


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