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Insight - How PS2 Connector Works

Written By: 

Abhimanyu Mathur

A gamer’s motion, a programmer’s voice, a DJ’s instrument and a designer’s brush; a single keyboard plays multiple roles in a computer. Similar is the case of a computer mouse that can make clicks to move a card in solitaire or open a web browser. For a computer buff of the current times, imagining a computer without these input accessories is impossible. Hence, it is utterly needed for these gadgets to tightly connect to the computer 24 x 7. Enabling a good connection are the PS2 connectors that have been in trend since a long time. 

Invented by IBM PCs, PS2 or personal station 2 connectors have reigned as sole connectors for keyboards and mouse for a long time. Easy manufacturing, ability to link tightly and fewer chances for connection error make it interesting to explore the insides of these connectors. 

Image of Mouse PS2 Connector with Six Input Ports

Fig. 1: Image of Mouse PS2 Connector with Six Input Ports


Figuring out whether a PS2 connector is for a keyboard or mouse is pretty easy. A mouse connector has a green plastic molding while that of a keyboard has a purple molding. Hence, the one in the image is a mouse connector.

Metal Box

This female PS2 connector has a boxed metal casing inside which the plastic molding is placed.  The six input ports of the connector are shown in the image above and corresponding to the input are six output pins placed at the bottom of the connector.
Bottom of Connector with Six Output Pins Projected Out
Fig. 2: Bottom of Connector with Six Output Pins Projected Out
Image Indicating Pin Pattern of Connector
Fig. 3: Image Indicating Pin Pattern of Connector 

Pin Diagram

Pin Diagram: Aforementioned, PS2 is a 6 pin connector. Its pin pattern has been mentioned below:
·                     Pin 1: Data
·                     Pin2: Not Connected
·                     Pin3: Ground
·                     Pin4: +5V (Vcc)
·                     Pin5: Clock
·                     Pin6: Not connected.
Pin 2 and pin 6 serve as mouse data and mouse clock splitter in some computer, respectively. The rectangular slot helps in ensuring correct orientation of the male connector when it is connected. This helps in protection of the pins from getting damaged.
Plastic Molding on Left and Metal Casing on Right
Fig. 4: Plastic Molding on Left and Metal Casing on Right 

Inside the metal box

Inside the metal box: The plastic molding can be seen after the outer metal casing is separated. Almost a cubical structure, it is made of light weight but sturdy material that can tolerate certain levels of stress.
Pin Layout in Plastic Molding
Fig. 5: Pin Layout in Plastic Molding


Pins: The face adjacent to the input ports has the metal contact pins extending out. They emerge out from a black colored platform which limits the soldering and protects the junction from where the pins come.

The pins are quite thin in their structure and are spaced sufficiently apart for easy connections. The pins can either be soldered or folded and attached to the PCB.
Pin Structure and Layout
Fig. 6: Pin Structure and Layout
Pin Extension: The pins come out from the opposite face of the input and then bend to extend from the face adjacent from the input port. The pins are not of same length but they do terminate at same point.
Image Showing Structure of Pins
Fig. 7: Image Showing Structure of Pins 

Structure of Pins

Structure of Pins: The structure of the pins is interesting to understand as it has a couple of bends that changes the orientation of its output pin. The first bend places it correctly over the platform and second band orients the pin in a vertically downward manner.
Also a bridge like structure is there which narrows down to a small opening from which input of a male connector is inserted.
Image Indicating Input Region of PS2 Connector Pin
Fig. 8: Image Indicating Input Region of PS2 Connector Pin
The image above shows the input region of a PS2 connector pin. A narrow opening ensures that input pin tightly adheres itself to the connector.