Mobile High-definition Link
The MHL (Mobile High-Definition Link) Consortium was formed to develop a new mobile audio/video interface standard for directly connecting mobile phones and other portable consumer electronics (CE) devices to high-definition televisions (HDTVs) and displays. The MHL standard features a single cable with a low pin-count interface able to support up to 1080p high-definition (HD) video and digital audio while simultaneously charging the connected device.
• The HDTV charges the connected device.
• Uses a single, thin cable to connect the mobile device to the HDTV.
• The HDTV remote will control the connected device with guaranteed mixed manufacturer interoperability.
• 1080p uncompressed HD video.
• 8 channel (e.g., 7.1 surround sound) uncompressed audio.
• Supports High-bandwidth Digital Content Protection (HDCP).
• MHL is connection agnostic (i.e., not tied to a specific type of hardware connector). The first implementations dual-purpose the most popular mobile connection (micro USB) and the most popular HDTV connection (HDMI). Other than the connectors being used, no USB or HDMI technology is being used. It is exclusively MHL signaling through the connectors and over the cable. Other proprietary and custom connections are also allowed.
By transporting the digital content in digital form, the full impact of the picture (whether still images or video) can be seen on HDTVs.
Silicon Image originally demonstrated a mobile interconnect, based on its TMDS technology, at the January 2008 Consumer Electronics Show (CES). This interface was termed "Mobile High Definition Link" at the time of the demonstration, and is a direct precursor of the implementation announced by the MHL Consortium.
The company is quoted as saying it did not ship that original technology in any volume, but used it as a way to get the working group started.
A Working Group was announced in September 2009 to develop a specification based on MHL Technology.
The MHL Consortium was announced by the companies of the Mobile High-definition Working Group on April 14, 2010.Nokia, Samsung, Silicon Image, Sony and Toshiba had been working on a specification since the Working Group announcement in September, 2009.
MHL, LLC is the agent for overseeing the licensing and promotion of the MHL specification.
An abridged version of the specification was made available for download on April 14, 2010 from http://www.mhlconsortium.org/. A nonrefundable fee of US$100 is charged.
The MHL 1.0 Specification was announced on June 30, 2010.
Details on adopter agreement are also available on the MHL Consortium website.
The Compliance Test Specification (CTS) was announced on December 21, 2010.
Almost immediately after the specification was announced, articles appeared highlighting the use of the industry-standard micro-USB connector to send high-definition video and audio, as well as take in power, and use a command bus between the mobile device and the TV. Some writers confuse the origins of MHL with that of HDMI, while also stating that MHL is based on Silicon Image's technology released in 2008.
Silicon Image announced a family of chips supporting MHL including a transmitter, a bridge and a port processor. Samsung announced at the 2011 Mobile World Congress their Galaxy S2 mobile device, with MHL output.
HTC announced at the 2011 CTIA their EVO 3D mobile device, with MHL output, and more recently that the Sensation will also have this capability, which it indeed has, as well as its successor, the Sensation XE.
The following retail products are known to have MHL technology available:
• Samsung Galaxy S II phone
• Samsung Infuse 4G phone (bundled with an MHL to HDMI adapter)
• Galaxy Nexus phone
• HTC Evo 3D phone
• HTC Flyer tablet
• HTC Sensation phone
• HTC Sensation XE phone
• HTC Amaze 4G phone
The Introduction of MHL
Mobile High-definition Link