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D Connectors

By Ajish Alfred February 15, 2013

D connectors are common electrical connectors especially found in the communication ports of the personal computer. The name is due to its ‘D’ shape itself. The D connector has two or more parallel rows of contacts surrounded by a ‘D’ shaped metal frame. The polarization is automatically achieved in this connector due to this ‘D’ shape. The D connectors were designed by the ITT Cannon in 1952. The D connectors have both male and female connectors and the pin numbers are available from 9 pin to 25 pin contacts.

Image of a male D connector

 Fig. 1: Image of a male D connector

The specifications of the D-standard connectors are defined by international standard, IEC 60807-3 / DIN 41652. Four different standard connectors are defined under this IEC standard. These connectors primarily differ from each other by their shell size and number of pins. They are named as DA, DB, DC, DD and DE connectors followed by their number of pins. For example the 15 pin standard A connector is named DA-15, the 25 pin standard B connector is named DB-25, the 37 pin C standard connector is named DC-37, the 50 pin D standard connector is named DD-50 and the recently introduced 9 pin E standard connector as DE-9 connector. Many manufactures refer the DE-9 connector as DB-9 since it came as a replacement for the DB-25 connector of the computers RS232 port.

The drawing of different D-standard connectors is shown in the following image.

Image showing standard D connectors

Fig. 2: Image showing standard D connectors

Most of these connectors are found as the peripheral connectors of PC. In the following image you can find a few D-standard connectors mounted on a PC cabinet.

Image showing D connectors mounted on a PC cabinet

            Fig. 3: Image showing D connectors mounted on a PC cabinet

The D connectors which do not follow the above discussed standard are also available like DE15 connectors usually found in VGA cables and High Density (HD) connectors like DB26HD, DB44HD, DB62HD, and DB78HD connectors etc. The D connectors are available with a maximum current rating of 40A and maximum voltage ratings up to 13,500 V.

Now let us go through the common applications and pin-out of some of the D-standard connectors.

DA-15 and DA-25 Connector

DA-15

The DA-15 pin is a 15 pin D-standard connector commonly used as game port of the computer. The game boards and joysticks are available which can be attached with this connector. The female connector is mounted on the PC cabinet and the male connector is found in the gaming device. The pin position of a DA-15 male connector is shown in the following figure.

Image of DA-15 connector

Fig. 4: Image of DA-15 connector

The pin-out of the 15 pin DA-15 connector for gaming device

PIN 1 ——————-+5V DC

PIN 2 ——————-BUTTON 1

PIN 3 ——————-X AXIS JOYSTICK 1

PIN 4 ——————-GROUND BUTTON 1

PIN 5 ——————-GROUND BUTTON 2

PIN 6 ——————-Y AXIS JOYSTICK 1

PIN 7 ——————-BUTTON 2

PIN 8 ——————-+5V DC

PIN 9 ——————-+5V DC

PIN 10 ——————BUTTON 4

PIN 11 ——————X AXIS JOYSTICK 2

PIN 12 ——————GROUND BUTTON 3 & 4

PIN 13 ——————Y AXIS JOYSTICK 2

PIN 14 ——————BUTTON 3

PIN 15 ——————+5V DC

DB-25

The DB-25 pin is a 25 pin D-standard connector commonly used in applications like RS-232 serial port, parallel port, parallel printer connector, multi-channel analog audio and AES digital audio etc. In PCs Female DB-25 connectors are used in parallel port and male DB-25 connectors are used in serial ports. The pin position of a DB-25 male connector is shown in the following figure.

Image of DB-25 connector

Fig. 5: Image of DB-25 connector

The pin-out of the 25 pin DB-25 connector for parallel port

 

PIN 1 ——————-STROBE

PIN 2 ——————-DATA 0

PIN 3 ——————- DATA 1

PIN 4 ——————- DATA 2

PIN 5 ——————- DATA 3

PIN 6 ——————- DATA 4

PIN 7 ——————- DATA 5

PIN 8 ——————- DATA 6

PIN 9 ——————- DATA 7

PIN 10 ——————ACK

PIN 11 ——————BUSY

PIN 12 ——————PAPER OUT

PIN 13 ——————SELECT

PIN 14 ——————LINE FEED

PIN 15 ——————ERROR

PIN 16 —————— RESET

PIN 17 ——————SELECT PRINTER

PIN 18 ——————GROUND

PIN 19 ——————GROUND

PIN 20 ——————GROUND

PIN 21 ——————GROUND

PIN 22 ——————GROUND

PIN 23 ——————GROUND

PIN 24 ——————GROUND

PIN 25 ——————GROUND

The pin-out of the 25 pin DB-25 connector for serial port

PIN 1 ——————-PROTECTIVE GROUND

PIN 2 ——————-TXD

PIN 3 ——————- RXD

PIN 4 ——————- RTS

PIN 5 ——————- CTS

PIN 6 ——————- DSR

PIN 7 ——————- GROUND

PIN 8 ——————- DCD

PIN 9 ——————- NOT CONNECTED

PIN 10 —————— NOT CONNECTED

PIN 11 —————— NOT CONNECTED

PIN 12 —————— NOT CONNECTED

PIN 13 —————— NOT CONNECTED

PIN 14 —————— NOT CONNECTED

PIN 15 —————— NOT CONNECTED

PIN 16 —————— NOT CONNECTED

PIN 17 —————— NOT CONNECTED

PIN 18 —————— NOT CONNECTED

PIN 19 —————— NOT CONNECTED

PIN 20 ——————DTR

PIN 21 —————— NOT CONNECTED

PIN 22 ——————RI

PIN 23 —————— NOT CONNECTED

PIN 24 —————— NOT CONNECTED

PIN 25 —————— NOT CONNECTED

DE-9 and DE-15 Connector

DE-9

This 9 pin DE-9 standard D connector is mostly referred to as DB-9 connector, but it is totally different in shell size and pin number of DB standard connector. They are applied as a replacement for the large DB-25 serial port in modern PCs. They are also used in token ring network, computer network, CAN etc. The pin position of a DE-9 male connector is shown in the following figure.

 

Image of DE-9 connector

 Fig. 6: Image of DE-9 connector

 

The pin-out of the 9 pin DE-9 connector for serial port

PIN 1 ——————- DCD

PIN 2 ——————- RXD

PIN 3 ——————- TXD

PIN 4 ——————- DTR

PIN 5 ——————- GROUND

PIN 6 ——————- DSR

PIN 7 ——————- RTS

PIN 8 ——————- CTS

PIN 9 ——————- RI

Pin description:

DTR: Data Terminal Ready, Indicates presence of DTE to DCE

DCD: Data Carrier Detect, DCE is connected to the telephone line

DSR: Data Set Ready, DCE is ready to receive commands or data

RI: Ring Indicator, DCE has detected an incoming ring signal on the telephone line

RTS: Request To Send           DTE requests the DCE prepare to receive data

CTS: Clear To Send, Indicates DCE is ready to accept data

TXD: Transmitted Data, Carries data from DTE to DCE

RXD: Received Data, Carries data from DCE to DTE

DE-15

This 15 pin connector is not actually a DE standard connector since its shell size and pin numbers are different from that of a DE standard connector. This connector is widely used as a connector for the VGA port of PC, monitors etc. The pin position of a DE-15 male connector is shown in the following figure.

Image of DE-15 connector

Fig. 7: Image of DE-15 connector

The pin-out of the 15 pin DE-15 connector for VGA port

PIN 1 ——————- RED

PIN 2 ——————- GREEN

PIN 3 ——————- BLUE

PIN 4 ——————- NOT USED

PIN 5 ——————- GROUND

PIN 6 ——————- RED GROUND

PIN 7 ——————- BLUE GROUND

PIN 8 ——————- GREEN GROUND

PIN 9 ——————- POSITIVE

PIN 10 —————— GROUND

PIN 11 —————— ID BIT 0

PIN 12 —————— DATA

PIN 13 —————— HORIZ SYNC

PIN 14 —————— VERT SYNC

PIN 15 —————— DATA

Sample specification:

Insulation Resistance ——————– 1,000M? min.

Dielectric Strenght ———————– 1,000 V AC min. for 1 minute

Voltage Rating —————————-  300V DC

Withstanding Voltage ——————-  500V AC for 1 Minute

Contact Resistance ———————–  20m? max.

Current Rating —————————–  1.5A

Summary

{C}{C}{C}{C}{C}·         {C}{C}{C}{C}{C}The name D connector is due to the ‘D’ shaped metal frame surrounding the contact pins

{C}{C}{C}{C}{C}·         {C}{C}{C}{C}{C}The D-shape automatically makes it polarized connector

{C}{C}{C}{C}{C}·         {C}{C}{C}{C}{C}The basic D-standard connectors are DA-15, DB-25, DC-37, DD-50 and DE-9 connectors.

{C}{C}{C}{C}{C}·         {C}{C}{C}{C}{C}DA-15 is used for gaming devices, DB-25 is used as parallel and serial port of PC, DE-9 is used as serial port in PC.

{C}{C}{C}{C}{C}·         {C}{C}{C}{C}{C}DE-9 connector when used as serial port in PC is otherwise referred to as DB-9 since it replaces large the DB-25 serial connector.


Filed Under: Tutorials
Tagged With: connector, d, da 15, da 25, de 15, de 9
 

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