Displayport will soon be able to run via USB type-c cable

The USB-IF and VESA organizations have announced the ‘DisplayPort Alternate Mode on USB Type-C Connector Standard’. The standard makes it possible to run Displayport video signal over the upcoming USB type-c cables.

The Alt Mode specification describes the transfer of lanes of the USB 3.1 signal from the USB type-c cable. That signal uses four lanes for the USB 3.1 data connection with a maximum theoretical speed of 10 Gbit/s. The displayport signal can take over a single lane, a pair or all four lanes. In the latter case, image transfer with the maximum ‘5k’ resolution of 5120×2880 pixels of displayport 1.3 is possible.

However, the maximum speed of USB 3.1 expires partly or completely when the lanes are seized. For example, if both standards use two lanes, USB 3.1 at reduced speed and a displayport image with 4k resolution can, for example, run side by side over a cable. This is possible, for example, for docking stations for laptops. The USB 2.0 signal is not affected at all and the power transfer remains possible, regardless of Alt Mode use. The displayport aux channel can also run via the usb type-c cable; this channel is reserved for connections other than video, such as audio, touchscreen data, hdcp and even usb.

Manufacturers will also be given the option of making USB type-c to DisplayPort cables, and displayport-side adapters will also be within reach, leading to the appearance of USB-to-HDMI 2.0 cables and variants with DVI and VGA. The DisplayPort Alternate Mode on USB Type-C Connector Standard makes USB the standard that means laptops and tablets only need a single cable for data and multimedia transfer, as well as for charging. The recently announced USB Power Delivery 2.0 specification now offers voltages of up to 5A with 5V, 12V and 20V, with a maximum power of 100W.