What is DVI?
DVI stands for Digital Visual Interface.
Designed by the Digital Display Working Group (DDWG) it provides a digital
to digital connection to maximize the quality of high end flat panel monitors
and video cards. When a video signal leaves the computer, it must be converted
to analog for transmission over a VGA cable and then converted again to
a digital signal at the monitor. Each conversion causes signal loss, affecting
the quality of the final image. DVI provides a direct digital connection
eliminating this conversion process.
How does DVI work?
DVI uses transition minimized differential
signaling (T.M.D.S.) protocol for the base electrical connection. The
DVI spec calls for at least one T.M.D.S. “link” which contains
three data channels (RGB) and one clock channel. Two “links”
can be used to increase the available bandwidth.
DVI-D and DVI-I
The DVI spec recognizes two types
of connectors, DVI-D and DVI-I.
DVI-D provides a direct digital
only connection. This Digital connection provides a faster, higher quality
signal than analog.
DVI-I provides a dual Digital/Analog connection.
The combination connector is intended to transition product from analog
to the fully digital connection over time. It can run either a digital
connection or an analog connection, but cannot cross between the two.
Single and Dual Link
Single Link DVI
: A single T.M.D.S. link supports a
maximum bandwidth of 165 Mhz and supports resolutions up to 1920x1080
at 60Hz or 1280x1024 at 85Hz.
Dual Link DVI
: Dual T.M.D.S. links doubles the maximum
bandwidth (2 x 165 Mhz) and supports resolutions up to 2048x1536 at 60
Hz or 1920x1080 at 85 Hz. |
