Apple's Lightning Digital AV Adapter is a Full-Fledged Computer
Panic, the developers behind apps like Coda and Transmit, spent some time disassembling the Lightning Digital AV cable that allows iOS devices like the iPad mini and the iPhone 5 to output HDMI to televisions.
The company discovered that, like its Lightning to 30-pin brethren, the Digital AV adapter is considerably more complicated than it would appear. Among other discoveries, Panic found an ARM chip and 256MB of RAM inside.
There are a lot of questions. What OS does it boot? @jmreid thinks the adapter copies over a “mini iOS” (!) from the device and boots it in a few seconds every time it’s connected, which would explain the fairly lengthy startup time for video out. Why do this crazy thing at all? All we can figure is that the small number of Lightning pins prevented them from doing raw HDMI period, and the elegance of the adapter trumped the need for traditional video out, so someone had to think seriously out of the box. Or maybe they want get as much functionality out of the iPad as possible to reduce cost and complexity.
Panic conjectures that for some reason the Lightning port isn't capable of outputting raw HDMI -- something that should give an extremely high quality image -- and instead uses a form of AirPlay to output video, delivering a lower quality video signal.
Update: Panic highlights this comment from an anonymous reader hinting at being an Apple engineer, which offers more details about how the adapter works and indicating that code updates are being made to improve the video quality.
The reason why this adapter exists is because Lightning is simply not capable of streaming a "raw" HDMI signal across the cable. Lightning is a serial bus. There is no clever wire multiplexing involved. Contrary to the opinions presented in this thread, we didn't do this to screw the customer. We did this to specifically shift the complexity of the "adapter" bit into the adapter itself, leaving the host hardware free of any concerns in regards to what was hanging off the other end of the Lightning cable. [...]
Certain people are aware that the quality could be better and others are working on it. For the time being, the quality was deemed to be suitably acceptable. Given the dynamic nature of the system (and the fact that the firmware is stored in RAM rather then ROM), updates **will** be made available as a part of future iOS updates. When this will happen I can't say for anonymous reasons, but these concerns haven't gone unnoticed.
Popular Stories
While the iPhone 17 Pro and iPhone 17 Pro Max are not expected to launch until September, there are already plenty of rumors about the devices.
Below, we recap key changes rumored for the iPhone 17 Pro models as of March 2025:
Aluminum frame: iPhone 17 Pro models are rumored to have an aluminum frame, whereas the iPhone 15 Pro and iPhone 16 Pro models have a titanium frame, and the iPhone ...
With the second release candidate of iOS 18.4 that Apple seeded out today, the company finally provided us with release notes that give a full rundown on what to expect.
There's an Apple Vision Pro app, new Apple Intelligence features for notifications and additional language support, plus an Apple News Food feature for Apple News+ subscribers, and several updates that should improve the...
Apple is reportedly working on a new Magic Mouse. Below, we recap what to expect.
The two key rumors for the Magic Mouse 3 so far include a relocated charging port, along with a more ergonomic design.
It was briefly rumored that the Magic Mouse 3 would also feature voice control, but that was misinterpreted information.
Relocated Charging Port
While the Magic Mouse switched from...
Apple's big developer event is a little over two months away, and rumors about what we can expect to see in Apple's next major operating system updates are becoming increasingly frequent.
A public release of iOS 18.4 is also imminent with a number of updates and improvements, although we won't be getting the major Apple Intelligence Siri upgrades that had reportedly been planned for this...
We've been hearing rumors about a foldable iPhone for almost a decade now, but it looks like we might finally see the device come to fruition in 2026. We're going to be waiting many more months for the foldable iPhone, but so far we're hearing good things.
Apple wants to make it creaseless. It's taken Apple multiple years to design a foldable iPhone that it's satisfied with because Apple ...
Multiple sources have claimed that iOS 19 will introduce a new design with more translucent buttons, menus, notification banners, and more, and there is now another clue that points towards this glass-like appearance.
Bloomberg's Mark Gurman today said the new design project is codenamed "Solarium" internally. A solarium is a room with glass walls that allow in plenty of sunlight, so this...
In the mid-to-late 2000s, Facebook was all about staying connected with friends and family. However, as the social media platform added new features and grew over time, that core experience began to get drowned out.
That changes starting now, according to Meta, which today introduced a new feature that will "bring back the joy" of classic Facebook.
Specifically, Meta has redesigned the...
Apple's next-generation iPad Pro models with the M5 chip will "launch this year," according to Bloomberg's Mark Gurman.
In his Power On newsletter today, Gurman said the new iPad Pro models have progressed to an "advanced testing" stage, and he expects mass production of the devices to begin in the second half of this year. If that timeframe is met, the new iPad Pro models could launch...
