MHL stands for Mobile High Definition Link, an upcoming connection technology developed by a consortium of partners including Nokia, Samsung, Sony, and Toshiba, amongst others. The goal of the consortium is for MHL to become the new standard for connecting portable electronic devices to external monitors – HD televisions for example. Unfortunately there is a lot of misinformation flying around the internet right now about exactly how it works, so I thought an explanation might help put the record straight.

So what does it do?

An MHL connection will allow you to connect your mobile phone, or other MHL enabled device, to a television via its HDMI input. Whatever is displayed on your mobiles screen will be shown on the television screen (this is called “mirroring” your display). The MHL cable will connect to your phones micro USB connection, so your device won’t need multiple ports for charging and TV Out functions.

Some connection types out there at the moment don’t have mirroring, they will only output certain kinds of content – typically video, images, and music. Mirroring lets you do so much more – play games from the phone on the television for a true portable gaming console experience, read ebooks, browse the web, send texts and emails – anything you can do on your phone is available to you on your’ television. In combination with other technologies like Bluetooth a world of possibilities opens up

But won’t I need a new MHL-capable television to use MHL?

No. This is a common misconception. Any television with an HDMI input will work with an MHL enabled device via an MHL cable. MHL capable televisions are meant to be coming to the market later this year, and they will extend the things that can be done over the MHL connection. Firstly, they will simultaneously charge the connected MHL device while mirroring its display, removing the need for a separate charging cable for the device. Second, the remote for the television will control media playback on the MHL device.

Hold on, so you’re telling me that if my television doesn’t have MHL, my phone won’t be charging while it’s connected? How can I watch a whole HD movie from my phone then? The battery isn’t going to get me through the rest of the day!

While it’s true that your MHL device will not charge over the MHL cable if your television isn’t MHL capable, there is a way around that. You will be able to enjoy simultaneous charging and playback, even with your non-MHL television. In the “How to” video above you’ll see te MHL adapter has a charging input.

In fact, the adapter actually won’t operate without a power source plugged in. Thats somewhat of a downer, since it means having a charger with you anywhere you want to use MHL, but the reality is that you’ll almost always want it – even whilst charging the handsets battery will dip a percentage point every few minutes when you’re doing intensive stuff like watching HD video.

Unfortunately there is currently no solution to allow your non-MHL television’s remote to control media playback on the phone (how would Sony, Toshiba, and Samsung sell you that shiny new HD TV later this year if they give you everything now?).

OK, this is all sounding pretty good, but what if my television is a Sony, but my MHL device is from Samsung?

Remember, this is going to become a connection standard, much in the same way that micro USB connections are standard in phones now across all manufacturers in the EU (Apple shenanigans aside). Your Sony/Samsung/Toshiba/whatever television, will work the same with any connected MHL device, regardless of the devices manufacturer.

Oh, cool, I saw the Galaxy SII has the ability to connect to USB drives – so I’ll be able to watch movies from an external hard drive via MHL, right?

Unfortunately not. The micro USB port detects what kind of cable or device it’s connected to, and goes into that mode, and only that mode. Think of it as throwing a switch, in one direction MHL is on, and USB is off, and in the other direction vice versa. They are mutually exclusive. When the next version of the MHL specification comes out there are a number of additional features they are considering adding, so it is possible we will see this in the future. Whether new features will be backwards compatible for devices with a previous version of the MHL specification, or not, is unknown for the time being.

What other information is out there about MHL?

For a really good video explanation of MHL, from a senior person at the MHL Consortium at this years’ Mobility World Conference, check out this link:

http://www.youtube.com/watch?v=ZtwTcnR0hqA