Digital Visual Interface - Connector

Connector

The DVI connector usually contains pins to pass the DVI-native digital video signals. In the case of dual link systems, additional pins provide increased bandwidth allowing higher resolutions and longer distances. Dual link should not be confused with dual display (also known as dual head), which is a configuration that involves a single computer connected to two monitors.

In addition to digital, the DVI connector includes pins that carry an analog signal, compatible with the RGBHV signals in a VGA connector. This allows a VGA monitor to be connected with a passive plug adapter and offers a universal solution for the DVI interface. The analog pins are the four that surround the flat blade as shown on the left-hand side of the diagrams for DVI-I and DVI-A.

The DVI connector on a device is therefore given one of three names, depending on which signals it implements:

• DVI-D (digital only, single-link or dual-link)
• DVI-A (analog only)
• DVI-I (integrated, combines digital and analog in the same connector; digital may be single- or dual-link)

The DVI-D and DVI-I connector provide (via additional pins) for a second data link. This allows resolutions up to 2560x1600, which are supported by many add-on graphic cards. A connector with these additional pins is sometimes referred to as DVI-DL (dual link).

The long flat pin on a DVI-I connector is wider than the same pin on a DVI-D connector, so it is not possible to connect a male DVI-I to a female DVI-D by removing the 4 analog pins. It is possible, however, to connect a male DVI-D cable to a female DVI-I connector. Many flat panel LCD monitors have only the DVI-D connection so that a DVI-D male to DVI-D male cable will suffice when connecting the monitor to a computer's DVI-I female connector.

DVI is the only widespread video standard that includes analog and digital transmission options in the same connector. Competing standards are exclusively digital: these include a system using low-voltage differential signaling (LVDS), known by its proprietary names FPD-Link (flat-panel display) and FLATLINK; and its successors, the LVDS Display Interface (LDI) and OpenLDI.

Some new DVD players, TV sets (including HDTV sets) and video projectors have DVI/HDCP connectors; these are physically the same as DVI connectors but transmit an encrypted signal using the HDCP protocol for copy protection. Computers with DVI video connectors can use many DVI-equipped HDTV sets as a display, but only computers whose graphics systems support High-bandwidth Digital Content Protection are currently able to play content that requires digital rights management.

USB signals are not incorporated into the connector, but were earlier incorporated into the VESA Plug and Display connector used by InFocus on their projector systems, and in the Apple Display Connector, which was used by Apple until 2005.

The DMS-59 connector is a way to combine two analog and two digital signals in one plug. It is commonly used when a single graphics card has two outputs. Note that this is dual display – it does not have the additional pins for the dual link TDMI signals.

M1-DA connectors are sometimes labeled as DVI-M1; they are used for the VESA Enhanced Video Connector and VESA Plug and Display schemes.

Note also that on the male DVI connector, pin 14 (+5 volts) is shorter than the other pins. This is intended to ensure that this is the last contact to mate when inserting a plug. In practice, it is possible to mate the pins at the opposite end to the analogue signals later if the connector is inserted at an angle.