Single chip Dockport solution activates DisplayPort and USB over a single cable

Single chip Dockport solution activates DisplayPort and USB over a single cable

DockPort provides a lower cost alternative to today’s proprietary implementations and offers more features than standard USB docking stations. It allows systems designers to build small, more affordable docking stations that connect and synchronize computers with LCD monitors, USB dongles, USB keyboard and mouse, Gigabit Ethernet, USB storage, audio speakers, DVD/Blu-ray media player and smartphone.

Texas Instruments, makers of the very line famous scientific calculator, has recently launched a single chip that delivers audio and video, USB data and power over a single cable between a notebook, ultrabook or tablet PC and a docking station or USB dongle. The HD3SS2521 controller allows DisplayPort, USB 3.0, USB 2.0 and power over a single interconnecting cable, and provides the control logic and automatic switching required on the cable’s host side and dock side.

A bidirectional two/one switch controls DockPort detection, as well as signal and power switching. It allows display, USB, power, and computer docking interface over a single cable, which allows designers to create smaller, more affordable docking stations. The 5 mm by 11 mm package reduces board space by one third and BOM costs by more than 50% compared to competitive implementations that provide data and A/V over a single connector.

Power and charging is delivered over the same cable, reducing the number of connections by enabling upstream charging of host side computers, or downstream powering of one or more dongles. Operating in a two lane mode with USB 3.0 data, the HD3SS2521 supports one monitor with resolutions up to 4K2Kp at 30 fps and 30 bpp, or multiple monitors with resolutions less than or equal to 1920 by 1200p at 60 fps. In four lane mode with USB 2.0, it completely the following configurations:

  • One 4K2Kp at 60 fps and 30 bpp
  • Two 4K2Kp monitors at 30 fps and 30 bpp
  • Four or more monitors with resolutions less than or equal to 1920 by 1200p at 60 fps

If you’re a system designer, you can extend DisplayPort reach, allow multiple video interface, and ass more switching and USB SuperSpeed ports by combing the HD3SS2521 with other Texas Instruments Interface products. Complementary products include the SN75DP130 DisplayPort 1:2 redriver switch, SN75DP126 DisplayPort 1:2 redriver switch, SN75DP139 DisplayPort to TMDS translator, HD3SS212 DisplayPort 1.2 2-to-1 differential switch, TUSB8040A1 four-port USB 3.0 hub, and HD3SS3412 four-channel differential switch.

A reference host side evaluation module (EVM) and dock side EVM are available to accelerate DockPort system development. The HD3SS2521 HSPICE model is also available to verify host and dock signal integrity. The HD3SS2521 is available today in a 56-pin WQFN package for a suggested retail price of US$1.85 in 1,000-unit quantities.

Vincent Clarke

Vincent Clarke is the Universal Serial Bus (USB) Guru for When he's not writing tutorials and catching up on the latest USB news, Vincent is busy preparing his next blog post and answering USB questions from his readers and subscribers.

Leave a Reply

Your email address will not be published. Required fields are marked *