All About D-Sub Connectors

D-sub connectors, or d-subminiature connectors is a group of plugs and sockets that are commonly used in the communications area of older PCs. For instance, the analog VGA monitor interface uses a d-subminiature 15-pin plug and socket. D-sub con connectors are also called DB connectors and d-subs. D-sub connectors come in 9, 15, 25, 37, and 50 pin variations. The D-sub designation doesn’t describe the purpose of each line, it defines the physical structure of the connector itself.

Widely used as a printer port for PCs was the female DB-25. When serial ports were still popular on PCs the second serial port was the male DB-25. The male DB-25 is still commonly used for RS-232 communication devices.

The DB-9 male connector otherwise known as the DE-9 was commonly used for the first serial port on older PCs. They were also used on other communication devices.

The DB 15, DA-15 and DE 15 are widely used connectors. The bigger two-row female DA-15 connector is used as the game port on a PC. The smaller three-row connectors is a female high density DE-15 connector that is used for a VGA port.

D-sub connectors are named for their signature d-shaped metal shield. When they were introduced they were some of the smallest connectors that were used on computer systems. D-sub connectors have two or more parallel rows of sockets or pins that are surrounded by a d-shaped metal shield. The part tht has the pin contacts is called the male connector or plug. The part that contains the socket is the female end.

D-sub connectors were invented by ITT Cannon in 1952. They used D as the prefix for numbering the whole series of connectors. The D was followed by A,B,C,D or E to note the shell size. That was followed by the number of pins or sockets on the connector.

Cannon also made combo D-sub connectors with larger contacts instead of some of the normal contacts that were used for high-current, high-voltage or coaxial inserts. One common variation was the DB-13W3. It was commonly used for high-performance video connections.

All About M24308 Connectors

Formerly known as the MIL-C-24308, the M24308 is a military connector that is sometimes termed the MIL-DTL-24308, the MIL-PRF-24308. This connector is the United States Military version of a D-subminiature connector it must meet very specific requirements. It has to be small enough to fit into small spaces and it has to be reliable enough to have a long use life. These connectors are often used for important and difficult tasks.

M24308 connectors are standard D-sub connectors. Military connectors are available in a wide variety of styles and formats. They also have variety of options when it comes to their mounting as they can be rigid or standard. They can also have different contacts including crimp, pin, socket, solder or insulation displacement. M24308 connectors can also be non-environmental, polarized shell, miniature, rack and panel. M24308 connectors have a wide temperature range and they can function between -55 degrees Celsius to +125 degrees Celsius.

These connectors are compact and they are efficient in the way they use space. These connectors are ideal for use with high density packages. These connectors can be used for everything from information technology to aircraft missiles and satellites. They are rather versatile.

When space and weight are an issue that needs to be considered and there are a lot of circuits that need to be accommodated the M24308 is a great connector to choose. The size of the m24308 makes it perfect for use with aircrafts and missiles along with related ground support systems. These connectors are frequently used for applications like military equipment, ground support devices, modems, information systems, computer peripheral equipment, communication systems, space flight equipment and industrial instrumentation.

These connectors are designed to primarily be used in rack and panel applications. If you use accessories and cable clamps they can be adapted for other cabling uses. M2308 connectors have solid, machined contacts that have the option for non-magnetic properties along with high-density layout plus it can be non-outgassing.

M24308 Connectors can be divided into variety of classes:

Connectors that are intended for use in applications where the temperature ranges from -55 degrees Celsius to +125 degrees Celsius are class G and N connectors.

When residual magnetism must be kept at low levels they are class N connectors.

When atmospheric pressures must be contained across walls or panels where connectors are mounted they are class H connectors.

When high reliability space applications are needed you can use class D. K, and M connectors.

About Modular Connectors

Originally designed for telephone wiring a modular connector is a type of electrical connector that is used for telephones and variety of other purposes. Some applications that once used larger more expensive connectors were converted to modular connectors. It is likely that the most known use of modular connectors are for telephone and Ethernet jacks.

Once known as registered jacks, modular connectors were originally accepted by the Federal Communications Commission in 1976.  The specifications of a registered jack defined the wiring patterns of the jacks instead of the physical dimensions of gender of the connector. They were covered by ISO standard 8877 used in the first ISDN system. Modular connectors have been used to provide low-voltage AC and DC power, but no clear standard exists for this application.

There are other names for modular connectors. Sometimes they are referred to as modular phone jack/plug. They are also known as RJ connector and Western Jack/plug. Modular connectors are called that because their original use was a novel system of cabling that was designed to make telephone equipment more modular.

General Cable Corp developed and patented modular connectors in 1974. They were made to replace the hard-wired connectors that were used on most Western Electric telephones at the time. They replaced screw terminals and bigger 3 and 4 pin telephone jacks that were used in buildings.

Modular connectors do have a gender. Male connectors are known as plugs. Female connectors are known as jacks, or sockets. Plugs are designed to terminate loose cords and cables. Jacks are used in fixed locations most commonly on the wall. It is not common to find a modular connector that has one end with a modular connector and the other end with a jack. Most of the time cables are connected with a male to male adapter that has two female jacks wired back to back.

Modular connectors are made to latch together. They have a spring-loaded tab that is on the plug and snaps into a jack which makes it so the plug cannot be pulled out. Most jacks are installed on a wall or pane with the tab side facing down. This makes it so it is easier to use the tab when your remove the plug.

About Press-Fit Connectors

There are many advantages to press-fit connectors. They are easily repaired, they are more environmentally friendly and they are more cost effective. Press-fit connectors are pressed through adequately dimensioned plated-through holes on a printed circuit board. This method is used as an alternative to soldering. There are a number of advantages to press-fit connectors versus soldered connectors. With press-fit connectors you get rid of a bunch of negative aspects that go along with soldering including thermal stress of PCB, cold solder joints, shorts, and the elimination of lead-free solder.

Manufacturers can avoid soldering when they use press-fit technology to assemble PCB electronics. To create press-fit connection a pin is pressed into a fitted plated-through hole in a PCB.  The connection is more secure than a soldered PCB.

There are a variety of different press-fit connectors that are made. There are press-fit connectors with solid pins that don’t contort when they are inserted. There are compliant pins that compress when they are inserted. The technology for solid press-fit connectors was developed first, but designers and manufacturers were worried that there would be board damage from the solid press-fit contacts. To fix the problem developers created compliant press-fit technology. Now, compliant pins are usually preferred because they require less demands on the PCB, they use less force when they are inserted and they have more reliable results and less damage. That being said, both types of press-fit connectors are still used.

There are also bi-spring power press-fit terminations. Despite the improved technology there is still a risk of damaging PCBs and backplans because of the extreme force required for proper insertion. Bi-spring power press-fit connectors limit these insertion forces. Mounting screws are added for increased stability during shock and vibration environments. Some bi-spring power press-fit connectors reduce the need for more expensive press-in equipment. When properly used press-fit connectors give you a strong and reliable connector.

Press-fit connectors are used in a variety of applications from data and communication to mechanics and transportation. They are dependable, functional and efficient which gives them a variety of more advantages over similar connectors. Press-fit connectors are very popular.