DisplayPort (DP) is a digital display interface developed by a consortium of PC and chip manufacturers and standardized by the Video Electronics Standards Association (VESA). The interface is primarily used to connect a video source to a display device such as a computer monitor, and it can also carry audio, USB, and other forms of data.
DisplayPort was designed to replace VGA, DVI, and FPD-Link. The interface is backward compatible with other interfaces, such as HDMI and DVI, through the use of either active or passive adapters.
DisplayPort is the first display interface to rely on packetized data transmission, a form of digital communication found in technologies such as Ethernet, USB, and PCI Express. It permits the use of internal and external display connections, and unlike legacy standards that transmit a clock signal with each output, the DisplayPort protocol is based on small data packets known as micro packets, which can embed the clock signal within the data stream. This allows for higher resolution using fewer pins. The use of data packets also makes DisplayPort extensible, meaning additional features can be added over time without significant changes to the physical interface.
DisplayPort can be used to transmit audio and video simultaneously, although each is optional and can be transmitted without the other. The video signal path can range from six to sixteen bits per color channel, and the audio path can have up to eight channels of 24-bit, 192 kHz PCM audio that is uncompressed. A bi-directional, half-duplex auxiliary channel carries device management and device control data for the Main Link, such as VESA EDID, MCCS, and DPMS standards. In addition, the interface is capable of carrying bi-directional USB signals.
The DisplayPort uses an LVDS signal protocol that is not compatible with DVI or HDMI. However, dual-mode DisplayPorts are designed to transmit a single-link DVI or HDMI protocol (TMDS) across the interface through the use of an external passive adapter. This adapter enables compatibility mode and converts the signal from 3.3 volts to 5 volts. For analog VGA/YPbPr and dual-link DVI, a powered active adapter is required for compatibility and does not rely on dual-mode. Active VGA adapters are powered by the DisplayPort connector directly, while active dual-link DVI adapters typically rely on an external power source such as USB.