Circular Connectors in Electronics

What are Circular Connectors?

Circular connectors are, quite simply, connectors for electronic devices that have a circular shape on one or both ends. These connectors can be of many different varieties, and they are often found used in heavy industrial and military applications. They are also common around the house, however, being used in applications as mundane as the coaxial cable connectors utilized to connect cable television lines to the back of the TV.

Circular connectors are prized because of their durability. Many circular connectors have either threaded components on the ends or lock in other ways that prevent them from being forcibly pulled out of their socket when they are connected. This makes them ideal solutions for situations where force may be applied to the cable that they terminate or where the environment may be one where it's likely that some sort of contaminant could be introduced into an open connection.

Circular connectors can be difficult to differentiate by looking at the connector itself. Looking at the type of pin arrangement in the connector can reveal which type it is and, in some cases, common forms of connectors are available in circular varieties for particularly rugged applications.


What Types of Circular Connectors exist?

There are many different types of circular connectors. They can be differentiated by the number of pins they have in them, the arrangement of the pins and even the specifications to which they are built. For example, the circular connectors used by hobbyists to connect simple devices to one another and the circular connectors used by musicians to hook instruments and other equipment together don't need to be built up to the specifications of the military, but there are mil spec connectors on the market available for those latter applications.

Some circular connectors are designed to work specifically in very tough environments. The connectors themselves are, in those cases, provided with accessories such as seals, back shells and other enhancements that make them more durable and better able to hold up to tough environmental pressures and, in some environments, a lot of accidental pulling that would likely detach the cable from its receptacle were it not so protected.

Circular connectors include an enormous range of different devices. From the RCA plugs on the back of a stereo receiver to the connectors that hook together the most sophisticated and expensive military equipment in the world, there is plenty of variety among these devices.

One other significant advantage of circular connectors is that they tend to take up a lot less space than do other types of connectors. With rectangular connectors, each connector may take up a different amount of space on a control board or the back of the computer and each may have a different shape to it, sometimes making it easy to get confused when hooking connections together. While there may be many types of circular connectors available on the market, what they all have in common is the fact that their circular design makes them unusually rugged and able to hold up to a lot of abuse.

Described below are some of the most common types of circular connectors and their applications.


What are DIN Connectors?

DIN connectors take their names from the Deutsches Institut für Normung. This organization sets the standard for electronic devices in Germany. There are many different types of connectors that fall under this classification. In fact, this particular classification doesn't necessarily specify any type of connector without a number accompanying it.

DIN connectors are most often associated with audio connectors, one of their first applications. They have expanded out to be used in many different types of connectors, however, in many different environments. For example, the connector that connects keyboards to computers has typically been a circular DIN connector. Now USB is very popular for keyboard connectors as well. Other versions of these connectors are much sturdier than keyboard connectors.

DIN connectors will generally have a number printed immediately after than that specifies what type of connector they are. For example, a DIN 41524 connector is different than a DIN 41612 connector.


How Do They Work?

A DIN connector works by ensuring that only one plug and one socket can come together when the connector is hooked up properly. They have a tab on the bottom of them that ensures proper alignment. Around the pins on the connector – which may be arranged in several different configurations – there is a metal shield. This metal shield prevents improper orientation of the connector and it also keeps the pins safe from harm.

The versatile nature of these connectors makes them among the most popular in use.


What Are They Used For?

As stated above, DIN connectors are very much associated with the music world. They are quite commonly seen on microphones and other PA equipment, where the connector provides excellent protection from damage and from being pulled free accidentally.

DIN connectors can be outfitted with so many different pin arrangements that their usages are incredibly broad. They are utilized in and tennis, on some computers they're utilized for serial port connectors and they are often used in home audio equipment, as well.


Field RJ45 Connectors

RJ-45 connectors are among the most common in the telecommunications world. These are modular connectors that make it quick and easy to hook up telephones to wall sockets. At one time, these connectors were also used for data connections, though they have been supplanted by different connectors over time.

RJ-45 field connectors are designed to be rugged and hold up to a great deal of abuse, much more than any home phone would ever be likely to experience. They often have circular designs that provide them with the same advantages that other circular connectors have.


How Do They Work?

RJ-45 connectors are utilized to carry telecommunications data. RJ-45 field connectors are designed to hold up to very strenuous conditions. They are often outfitted with a very sturdy plate that allows them to be mounted in a wall or, in some cases, they have a threaded circular connector design that allow shielding to be placed over the junction, protecting it from harm.


What Are They Used For?

Field connectors are the workhorses of the RJ-45 connector family. These are designed to ensure that the telecommunications equipment is prevented from becoming detached and, in some cases, to prevent the junction from being exposed to environmental contaminants. These are very common pieces of equipment, particularly in industrial settings.


Industrial & Automation Circular Connectors

Circular connectors designed for industrial automation and control are very sturdy devices. They typically have more screws affixing them to whatever surface they are mounted to and are designed to keep out contaminants. Industrial and automation circular connectors come in many different types and, of course, because there are so many different types of circular connectors, this is a necessity. Some circular connectors are designed to project a bit from the surface to which they are mounted and others are designed to remain flush or be recessed somewhat.


How Do They Work?

The main thing industrial and automation circular connectors provide is security. These are designed so that a system of locks or a threaded connection prevents the cable from being pulled free. This also provides a seal, eliminating the threat of environmental contaminants entering into the connections and causing problems with machinery.


What Are They Used For?

These connectors will generally be seen in factories, at work sites where conditions are very dirty and trying and in other settings where the security of the connection needs to be maintained but where the environment, to some extent, makes that a very difficult thing to do.


Mil Spec Circular Connectors

Militaries are heavy users of circular connectors, owing to the strength of the devices and to the particularly difficult challenges that the military puts electronic equipment through. Mil spec circular connectors are built to the standards of the military, allowing them to be used in military grade applications. They are generally sturdier, more weatherproof and better insulated against contaminants than other industrial connectors. These connectors come in a variety of different designs and configurations.


How Do They Work?

Tough materials and good designs make mil spec circular connectors suitable for the rugged jobs that they are tasked with. These connectors are often extremely tough, and the methods by which the connectors are fastened together ensures that there is a very low likelihood of a cable being pulled free accidentally. The design also ensures that solid connections are always made when components are joined together by the connector.


What Are They Used For?

Mil spec connectors, of course, are used for military applications. They may be used in the electronics on the battlefield or they may be used in electronics that are located in very comfortable offices in a military's home nation. Either way, these connectors are designed so that they conform to the specifications that the military expects and, because of that, they are able to be used in any application that the military has a need for.


What Types of Circular Connector Accessories Exist?

The strength and reliability of circular connectors is often enhanced by adding accessories to the connections. Circular connector accessories provide insulation from the environment, they provide protection from mechanical force exerted against the connector and more. Often, the accessories also simply make it easier to connect devices together that may not actually have the same type of circular connectors or which may have a combination of circular and other types of connectors on them.


Circular Connector Adapters

Circular connector adapters are often used to extend the available length of a cable or to simply join two pieces of equipment together. These connectors will be specified as having a male or female gender on either and will be differentiated by size. They also have various body orientations. Some of them are designed to join two cables together in a straight line and others are designed to create a curved or bent junction.


Circular Connector Backshells

Circular connector backshells provide an extra layer of protection for circular connectors. They are placed on the end of the cable, providing a threaded device that can be screwed into a connector or simply providing a metal connector that can be slid over the top of the connection to provide additional protection for the connection itself. These are available in a wide variety of different materials and, like adapters, they can be purchased in designs that are straight or angled to some degree, to comedy different cabling arrangements.


Circular Connector Contacts

Circular connector contacts provide the means by which data and electrical signals can be transmitted between the two connected devices. The connectors are available separately so that they can be installed by people with the requisite engineering skills and so that customized devices can be made easily. These can be ordered to replace broken pins in a circular connector or they can be ordered to create a circular connector from scratch.


Circular Connector Inserts

Circular connector inserts provide the interior of a circular connector, designed in one of the standardized types. For people who are making circular connectors on their own, these provide either the receiving end of the circular connector or the end that is provided with the actual pins into which the receiving end of the connector is plugged. These range in complexity from multi-pin inserts to simple coaxial receivers and RCA plug receivers. They are differentiated by gender, the number of pins and what type of cable they are intended to be used with.


Circular Connector Seals

Some environments are rugged enough that circular connectors need to be further sealed against damage. This is where circular connector seals come into play. They are added to the devices to provide some extra protection against contaminants and can make a connection much more durable than it would be otherwise. These include gaskets that are added to the panel where the connector is bolted down, backshells that are designed to provide sealing capability and more. In certain applications, these types of seals may be called for to protect equipment from accidental damage.