An Introduction to VGA and its pinout

An Introduction to VGA

VGA was introduced in 1987 and is abbreviated for “Video Graphics Array” this system was introduced as an interface between a computer and its corresponding monitor. Since its introduction several other standards have been introduced offering greater resolutions; i.e. SVGA, XGA SXGA & UXGA.
For an understanding of these resolutions and corresponding pixels and scan rates - see Understanding Resolutions, Pixels & Scan Rates.
As The AV Guide is an “Easy Guide for the Home User” we do not wish to go into depth on the subject of VGA – only where it is applicable to Plasma’s, LCD’s and Projectors.

It is important to understand that all Plasma Screens, LCD’s and Projectors were actually designed to receive computer images and they are therefore basically computer monitors. The first Plasma’s, only used to offer a 15pin D-Sub (VGA) input for a VGA - RGBHV signal only.

Due to the fast technology advancement, these display devices were quickly introduced into the Home Theatre Market. Today most Plasma Screens, LCD’s and Projectors offer standard A/V connections which means that they have a built in scaler that converts from the standard AV signal to a higher grade signal; although the quality of these scalers differ vastly.
See page on Understanding Scalers.
Please Note: there is common misunderstanding of the term VGA – VGA is a RGBHV type video signal that is sent from a PC to any monitor and is strictly speaking not a connector type.

The actual connector is called a 15pin D-Sub

VGA is carried via a 15pin D-Sub Connector.

i.e.

The common Scart can carry composite, S-Video & RGB providing the scart sockets on both the sending & receiving devices have been wired for either S-Video / RGB or both. Likewise; the 15pin D-Sub Connector is the same in context – it can carry the standard VGA- RGBHV video signal plus RGBS, RGB sync on green and Component Video (Y/Pb/PR) providing the 15pin D-sub connector sockets have been wired for the purpose. REMEMBER - all signals delivered via a 15pin D-Sub (VGA) connector will be analogue only.

15-pin D-Sub (VGA) Connector Pinout

1. Red out	6. Red return	11. Monitor ID 0 in
2. Green out	7. Green return (ground)	12. Monitor ID 1 in or data from display
3. Blue out	8. Blue return (ground)	13. Horizontal Sync out
4. Unused	9.	14. Vertical sync
5. Ground	10. Sync return (ground)	15. Monitor ID 3 in or data clock

From the chart above, the 15pin D-Sub Connector has three separate connectors for the red, green and blue colour signals, and two connectors for the horizontal and vertical sync signals. In a normal standard AV analogue signal – the three colours can be wired together outputting a composite video signal or the colours separated as above but the two Horizontal & Vertical Syncs wired together giving you an RGB signal via scart. The separation of the signals is one reason why a computer monitor can have so many more pixels than a TV set.

Thanks to:
http://www.theavguide.co.uk/view_page.php?cat=8&&page=25#