Silicon Image, one of the founding companies of the HDMI standard, originally demonstrated a mobile interconnect at the January 2008 Consumer Electronics Show (CES), based on its transition-minimized differential signaling (TMDS) technology.

[4][5] 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.

[6] The working group was announced in September 2009,[7] and the MHL Consortium founded in April 2010 by Nokia, Samsung, Silicon Image, Sony and Toshiba.

There are a total of five pins used in MHL rather than the 19 used in HDMI, namely: a differential pair for data, a bi-directional control channel (CBUS), power charging supply, and ground.

This permits a much lighter cable and a much smaller connector on the mobile device, as a typical MHL source will be shared with USB 2.0 on a standard 5-pin Micro-USB receptacle.

The use of the power line in this way differs from HDMI, which expects the source to provide 55 mA for the purpose of reading the EDID of a display.

MHL uses the same Transition-minimized differential signaling (TMDS) as HDMI to carry video, audio, and auxiliary data.

Version 1.0 was introduced in June 2010, supporting uncompressed HD video up to 720p/1080i 60 Hz (with RGB and YCbCr 4:2:2/4:4:4 pixel encoding).

[19] Other features include 192 kHz 24-bit LPCM 8-channel surround sound audio, HDCP 1.4 content protection, and a minimum of 2.5 W (500 mA) power between sink (e.g., TV) and source (e.g., mobile phone) for charging.

[19] Version 2.0 was introduced in April 2012, and raised the minimum charging supply to 4.5 W (900 mA), with an optional 7.5 W (1.5 A) maximum allowed.

[20] Version 3.0 was introduced in August 2013, and added support for 4K Ultra HD (3840 × 2160) 30 Hz video, increasing the maximum bandwidth from 3 Gbit/s to 6 Gbit/s.

The specification increased the speed of the bi-directional data channel from 1 Mbit/s to 75 Mbit/s to enable concurrent 4K video and human interface device (HID) support, such as mice, keyboards, touchscreens, and game controllers.

[21] Other features include support for simultaneous multiple displays, improved Remote Control Protocol (RCP) with new commands, and HDCP 2.2 content protection.

superMHL 1.0 was introduced in January 2015, supporting 8K Ultra HD (7680 × 4320) 120 Hz High Dynamic Range (HDR) video with wide color gamut (Rec.

[2][22][23] Support for object-based audio formats were added, such as Dolby Atmos and DTS:X, with an audio-only mode also available.

The specification introduces a reversible 32-pin superMHL connector, which (along with USB Type-C) supports a higher charging power of up to 40 W (20 V / 2 A), and is designed for future bandwidth expansion.

The first Samsung MHL 1.0 smart adapter released with the Galaxy S III requires external power and is able to work with HDMI TVs at 1080p at 24 Hz.

The USB Type-C port controller functions as a switch and multiplexer, passing the MHL signal through to the external devices.