Apple Display Connector
Encyclopedia
The Apple Display Connector (ADC) is a proprietary modification of the DVI connector that combines analog and digital video signals, USB
, and power all in one cable
. Apple
used ADC for its LCD
-based Apple Cinema Displays and their final CRT
displays, before deciding to use standard DVI connectors on later models.
First implemented in the July 2000 Power Mac G4 and G4 Cube
, ADC disappeared from displays in June 2004 when Apple introduced the aluminum-clad 20", 23", and 30" Apple Cinema Display
s, which feature separate DVI
, USB
and FireWire connectors, and their own power supplies. The ADC was still standard on the Power Mac G5
until April 2005, when new models meant the only remaining Apple product with an ADC interface was the single processor Power Mac G5 introduced in October 2004. This single processor Power Mac G5 was discontinued soon after in June 2005.
, is physically incompatible with a standard DVI connector, as was previously used in the PowerBook G4 and the older Power Mac G4. The Apple DVI to ADC Adapter, which cost $149US at launch but is now available for $99US, takes USB and DVI connections from the computer, together with power, and combines them into an ADC connection, allowing ADC monitors to be used with DVI-based machines.
The initial implementation of ADC on some models of Power Mac G4s involved the removal of DVI
connectors from these computers. This change necessitated a passive ADC to DVI adapter to use a DVI monitor.
The ADC carries up to 100 W of power, an insufficient amount to run most 19-inch or bigger CRTs widely available during ADC's debut, nor can it run contemporary flat panels marketed for home entertainment (many of which support DVI or VGA connections) without an adapter. The power limit was an important factor for Apple to abandon ADC when it launched the 30-inch Apple Cinema HD Display. Power is supplied to the ADC port by a finger connector on the video card, which plugs into a slot on the motherboard between the AGP slot and the back panel of the computer.
On newer DVI-based displays lacking ADC, Apple still opted for a single "ganged cable" that connects the separate signal cables to each other so they cannot tangle. Such cables, however, employ standard DVI, power, USB and FireWire connectors, avoiding drawbacks to ADC. As of 2011, Apple no longer uses a DVI-based interface for any of its displays, preferring the increasingly common DisplayPort
signalling standard.
Universal Serial Bus
USB is an industry standard developed in the mid-1990s that defines the cables, connectors and protocols used in a bus for connection, communication and power supply between computers and electronic devices....
, and power all in one cable
Cable
A cable is two or more wires running side by side and bonded, twisted or braided together to form a single assembly. In mechanics cables, otherwise known as wire ropes, are used for lifting, hauling and towing or conveying force through tension. In electrical engineering cables are used to carry...
. Apple
Apple Computer
Apple Inc. is an American multinational corporation that designs and markets consumer electronics, computer software, and personal computers. The company's best-known hardware products include the Macintosh line of computers, the iPod, the iPhone and the iPad...
used ADC for its LCD
Liquid crystal display
A liquid crystal display is a flat panel display, electronic visual display, or video display that uses the light modulating properties of liquid crystals . LCs do not emit light directly....
-based Apple Cinema Displays and their final CRT
Cathode ray tube
The cathode ray tube is a vacuum tube containing an electron gun and a fluorescent screen used to view images. It has a means to accelerate and deflect the electron beam onto the fluorescent screen to create the images. The image may represent electrical waveforms , pictures , radar targets and...
displays, before deciding to use standard DVI connectors on later models.
First implemented in the July 2000 Power Mac G4 and G4 Cube
Power Mac G4 Cube
The Power Mac G4 Cube was a small form factor Macintosh personal computer from Apple Inc. It was sold from 2000 to 2001. Its cube shape is reminiscent of the NeXTcube from NeXT, acquired by Apple in 1996. The machine was designed by Apple industrial designer Jonathan Ive...
, ADC disappeared from displays in June 2004 when Apple introduced the aluminum-clad 20", 23", and 30" Apple Cinema Display
Apple Cinema Display
The Apple Cinema Display was a line of flat panel computer monitors introduced in September 1999 by Apple Inc. It was initially sold alongside the older line of Studio Displays, but eventually replaced them. In July 2011, Apple replaced it with the Apple Thunderbolt Display...
s, which feature separate DVI
Digital Visual Interface
The Digital Visual Interface is a video interface standard covering the transmission of video between a source device and a display device. The DVI standard has achieved widespread acceptance in the PC industry, both in desktop PCs and monitors...
, USB
Universal Serial Bus
USB is an industry standard developed in the mid-1990s that defines the cables, connectors and protocols used in a bus for connection, communication and power supply between computers and electronic devices....
and FireWire connectors, and their own power supplies. The ADC was still standard on the Power Mac G5
Power Mac G5
The Power Mac G5 is Apple's marketing name for models of the Power Macintosh that contains the IBM PowerPC G5 CPU. The professional-grade computer was the most powerful in Apple's lineup when it was introduced, widely hailed as the first 64-bit PC, and was touted by Apple as the fastest personal...
until April 2005, when new models meant the only remaining Apple product with an ADC interface was the single processor Power Mac G5 introduced in October 2004. This single processor Power Mac G5 was discontinued soon after in June 2005.
Compatibility
The Apple Display Connector, first debuted in the Apple Studio DisplayApple Studio Display
The Apple Studio Displays were a series of displays manufactured by Apple Computer Inc. that both used LCD and CRT as their displays. The Apple Studio Displays used DB-15, VGA, DVI, and ADC as their display output...
, is physically incompatible with a standard DVI connector, as was previously used in the PowerBook G4 and the older Power Mac G4. The Apple DVI to ADC Adapter, which cost $149US at launch but is now available for $99US, takes USB and DVI connections from the computer, together with power, and combines them into an ADC connection, allowing ADC monitors to be used with DVI-based machines.
The initial implementation of ADC on some models of Power Mac G4s involved the removal of DVI
Digital Visual Interface
The Digital Visual Interface is a video interface standard covering the transmission of video between a source device and a display device. The DVI standard has achieved widespread acceptance in the PC industry, both in desktop PCs and monitors...
connectors from these computers. This change necessitated a passive ADC to DVI adapter to use a DVI monitor.
The ADC carries up to 100 W of power, an insufficient amount to run most 19-inch or bigger CRTs widely available during ADC's debut, nor can it run contemporary flat panels marketed for home entertainment (many of which support DVI or VGA connections) without an adapter. The power limit was an important factor for Apple to abandon ADC when it launched the 30-inch Apple Cinema HD Display. Power is supplied to the ADC port by a finger connector on the video card, which plugs into a slot on the motherboard between the AGP slot and the back panel of the computer.
On newer DVI-based displays lacking ADC, Apple still opted for a single "ganged cable" that connects the separate signal cables to each other so they cannot tangle. Such cables, however, employ standard DVI, power, USB and FireWire connectors, avoiding drawbacks to ADC. As of 2011, Apple no longer uses a DVI-based interface for any of its displays, preferring the increasingly common DisplayPort
DisplayPort
DisplayPort is a digital display interface standard produced by the Video Electronics Standards Association . The specification defines a royalty-free digital interconnect for audio and video. The interface is primarily used to connect a video source to a display device such as a computer monitor...
signalling standard.