3.5 mm Audio

Posted on March 7, 2016 by KVMGalore   |  0 comments

3.5 mm TRS plug3.5 mm connectors (jacks and sockets) are the most commonly used audio connectors for headphones or audio output signals on MP3 players, smartphones and computers.

3.5 mm audio connectors are also termed stereo plug, mini-stereo, mini jack, headphone jack and microphone jack.

The connector is cylindrical in shape, typically with two, three or four contacts. Three-contact versions are known as TRS connectors, where T stands for "tip", R stands for "ring" and S stands for "sleeve". Similarly, two- and four-contact versions are called TS and TRRS connectors respectively.

This type connector was invented for use in telephone switchboards in the 19th century, AKA phone connector. In its original configuration, the outside diameter of the "sleeve" conductor was ¼ inch. The 3.5 mm (approx. ⅛ inch) version is also known as the miniature (or mini) version of a phone connector.

The most immediately recognizable 3.5 mm (⅛") connector is the version often seen as the plug on the end of a pair of headphones.

The 3.5 mm (miniature) size was originally designed as a two-conductor connector for earpieces on transistor radios. The 3.5 mm connector, which is the most commonly used in portable application today, has been around at least since the Sony EFM-117J radio which was released in 1964. It became very popular with its application on the Walkman in 1979.

3.5 mm TRRS connector plugThree- four- and five-conductor versions of the 3.5 mm plug are used for certain applications.

A three-conductor version is often used in MP3 music players, iPods and smartphones, providing stereo sound.

A four-conductor version is often used in compact camcorders and portable media players, and sometimes also in laptop computers and smartphones, providing stereo sound plus a video signal.

Proprietary interfaces using both four- and five-conductor versions also exist, where the extra conductors are used to supply power for accessories. The four-conductor 3.5 mm plug is also used as a speaker-microphone connector on handheld amateur radio transceivers and on mobile phones.

The most common arrangement remains to have the male plug on the cable and the female socket mounted in a piece of equipment: the original intention of the design.

A considerable variety of line plugs and panel sockets is available, including plugs suiting various cable sizes, right-angle plugs, and both plugs and sockets in a variety of price ranges.