25-Pin D-Sub Connector

25-Pin D-Sub Connector, Size 20 Contacts, Insert Arrangements

25 pin D Sub-miniature Connector, Standard Density

This connector may be terminated using any of the following terminal styles; Crimp, Solder, Insulation displacement contact (IDC), or Printed wiring board (PWB).
There are three general types; Standard density (size 20 contacts), High density (size 22D contacts), and Standard density (size 20 IDC contacts)

D-Sub Connector Insert Arrangements [D-Subminiature sizes]

Refer to MIL-DTL-24308; [Connectors, Electric, Rectangular, Non-environmental, Miniature, Polarized Shell, Rack and Panel]. The signal assignments are shown for the male connector, the female connector would have its pin outs mirrored.

D-Sub Connector Dimensions [D-Subminiature Case Out-line]
Military D-Sub Connector Manufacturers [MIL-C-24308 Vendors]

The 25-pin D-sub connector together with the 9-pin D-sub are the two most common connector sizes used with personal computers. The 25-pin DB connector was used as the PC Parallel Port connecting to printers or other devices before they started using smaller connectors. Like many connectors used on the back of PCs the connectors were color coded to assist in making interconnections. The red DB26 connector to the left is color coded to the standard color used for the 25-pin connector. A 25 pin Dsub connector is also used for a number of applications. The EIA-530 calls out a DB25 connector. In addition the RS232 specification [EIA232] calls out a 25 pin DSub. A common DB25 pin panel mount connector used as a serial port is shown to the left. The signal assignments for either of the two standards are provided on the electrical interface pages.

Of course 25-pin D connectors can be made to carry any type of signal including analog signals. Many devices use 3 terminal audio XLR connectors, as a positive and negative signal and ground. The two 25-pin D connector pin outs shown below each carry eight XLR signal pairs and is another example of the usage of a DB25 connector.

Unlike the other electrical standards listed above, the usage of the 25 pin connector shown above is undocumented. That is, there is no released specification that covers the pin assignments.