Apple's Lightning Connector Uses Adaptive Technology to Dynamically Assign Pin Functions

[MacRumors]

With Apple's new Lightning connector on the iPhone 5 dropping to just eight contact pins from the 30 pins seen in the original dock connector and gaining the ability to be inserted in either orientation, many have wondered just how Apple has been able to maintain most of the functions of the original dock connector. Others have wondered why Apple simply didn't shift to micro-USB, an existing standard in a comparable form factor.

Developer Rainer Brockerhoff has been examining Lightning's technical features and over the weekend outlined his thinking on how the "adaptive" nature of the Lightning connector highlighted by Apple during the technology's introduction at the iPhone 5 media event has enabled flexible functionality with a minimum of pins. Brockerhoff notes that the Lightning connector appears able to sense what kinds of devices are being connected and to use chips embedded in the cable to assign pin functionalities appropriate for each situation.

- The device watches for a momentary short on all pins (by the leading edge of the plug) to detect plug insertion/removal.

- The pins on the plug are deactivated until after the plug is fully inserted, when a wake-up signal on one of the pins cues the chip inside the plug. This avoids any shorting hazard while the plug isn't inside the connector.

- The controller/driver chip tells the device what type it is, and for cases like the Lightning-to-USB cable whether a charger (that sends power) or a device (that needs power) is on the other end.

- The device can then switch the other pins between the SoC's data lines or the power circuitry, as needed in each case.

- Once everything is properly set up, the controller/driver chip gets digital signals from the SoC and converts them - via serial/parallel, ADC/DAC, differential drivers or whatever - to whatever is needed by the interface on the other end of the adapter or cable. It could even re-encode these signals to some other format to use fewer wires, gain noise-immunity or whatever, and re-decode them on the other end; it's all flexible. It could even convert to optical.

Double Helix Cables has now shared with AppleInsider a mapping of the pins on the two sides of the Lightning connector, demonstrating that this adaptive assignment of pin functions is required for the reversible nature of the plug.

"Take top pin 2 for example," he wrote in an e-mail to AppleInsider. "It is contiguous, electrically, with bottom pin 2. So, as the plug is inserted into the iPhone, if you have the cable in one way, pin 2 would go into the left side of the jack, flip it the other way and the same pair of pins is going to match up with the other side of the jack (as the electrical contacts in the iPhone's jacks are along the bottom)."

Mapping of pins in Apple's new Lightning connector

The adaptive nature of the Lightning connector may explain to some degree the rather high cost of cables and adapters for the new standard, as the $29 and $39 adapters for connecting 30-pin dock accessories to Lightning-equipped devices are required to contain hardware capable of working with the dynamically assigned pin functions. In addition, the adaptive nature indicates that the same Lightning interface could evolve over time to support new technologies within existing hardware.

Article Link: Apple's Lightning Connector Uses Adaptive Technology to Dynamically Assign Pin Functions

[Andrewdodson]

I don't get it.

[jtp098]

I guess I should cancel my ebay orders for third party adapters

[GeekLawyer]

Originally Posted by jtp098

I guess I should cancel my ebay orders for third party adapters

I'd say that's a reasonable assumption.

[BTGeekboy]

I had a hunch Lightning was this sort of expandable.

It seems as if USB 3 is possible over the connector, given that both the phone and the cable support it (and the device on the other end, of course). This doesn't mean that iPhone 5 will ever be able to, but maybe 5++/5S/6/whatever will, without requiring yet another new connector.

(Or, even better, Thunderbolt, but let's not get ahead of ourselves here.)

[AppleFan115]

Amazing. When does the Samsung version come out?

Note: I do love Samsung TVs but sometimes the things they do just make me laugh. It will be extra funny when they do adopt it because they just bashed it in their printed ad.

[hlfway2anywhere]

oh and all this time i thought they'd changed the connector for NO REASON whatsoever.

/s

[jtp098]

Originally Posted by GeekLawyer

I'd say that's a reasonable assumption.

yea it's totally not worth having to ship them back in the end. Hopefully in a few months this will change

[Gav2k]

Waits for the eu bods to chime in.....

[troop231]

Still holding out for cheaper, longer 3rd party cables.

[swarmster]

Can we get back to how Apple's lazy designers don't do anything now? Please?

Unlike Samsung, which is super busy innovating stunning new ways to silently remote wipe phones with HTML.

[Colman]

So cheap cables should work for charging but nothing else?

[Yr Blues]

I'm hoping they can make the iPad charge faster once it's implemented on the device.

[everything-i]

Originally Posted by AppleFan115

Amazing. When does the Samsung version come out?

Probably about 6 months, Apple have done all the hard work in developing the concept after all

[JuBe]

I mean, wouldn't it be practical to have the same connection across all devices, that can do data and power, like was touted? Or is it not thin enough?

[SockRolid]

Apple was granted a patent on connectors with adaptive pin assignment about a year and a half ago. Lightning appears to be the first implementation of that technology. Nice.

[iParis]

Wouldn't it technically be an 16-pin adaptor, 17 if you count the whole thing as one, since it's reversible and there's pin's on both sides?

[imgmkr]

it's gonna be one for all cable, eh! coolio.
although it is pricy it would be handy and useful more and more later.

[jicon]

Can anyone comment on the length of the adapter included with iPhone5? Is it the same length as the iPad/iPhone4, or is it now capable of being a bit longer? Really looking for a cable another foot or two longer than the standard 30pin to USB adapter.

[H2SO4]

Originally Posted by SockRolid

Apple was granted a patent on connectors with adaptive pin assignment about a year and a half ago. Lightning appears to be the first implementation of that technology. Nice.

I think the problem with the iPhone 5 is that it doesn't feel like a stellar leap. The biggest changes are on the inside and this isn't really that tangible to your average consumer.

[troop231]

Originally Posted by jicon

Can anyone comment on the length of the adapter included with iPhone5? Is it the same length as the iPad/iPhone4, or is it now capable of being a bit longer? Really looking for a cable another foot or two longer than the standard 30pin to USB adapter.

It's the same length, but you can use a USB extension.

[iapplelove]

can't wait for the ipad to get on board,using one cable to charge both devices is so much easier.

[iParis]

Originally Posted by jicon

Can anyone comment on the length of the adapter included with iPhone5? Is it the same length as the iPad/iPhone4, or is it now capable of being a bit longer? Really looking for a cable another foot or two longer than the standard 30pin to USB adapter.

I'm guessing you're talking about the lightning USB cord since it doesn't come with an adaptor. It's the same length as the previous 30-pin cord.

[Dwalls90]

I'm really glad there is more to this switch in connector technology, then just changing the adapter.

[ThatsMrsGeek2U]

this seems amazingly forward thinking, thankfully. it hurts to have to change cables and i figured that there needed to be a better reason than just size and i was really hoping it was not different than a mini usb just for the sake of it. this makes me happy, it shows really thought and real innovation is still going on.
we got 9 years out of the last cable, hopefully in 9 years from now cables will be a thing of the past