We’re quickly learning more about how the new Lightning cable and port on the iPhone 5 interact. A cabling expert told AppleInsider the eight pins on each side of the cable are dynamically assigned. A special chip in the iPhone 5 assigns each pin.
Peter Bradstock from Double Helix Cables said that dynamic assignment by the new iPhone is what allows the cable to be inserted in either direction. The iPhone 5 reads the type of data from the pins and then adjusts according to the orientation that the cable was inserted.
“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).”
Bradstock also was the first to find last week that Apple’s Lightning cable has an authentication chip. With that special chip, it is highly unlikely that other, cheaper Lightning options found on Amazon and eBay will even be functional.
As most iPhone 5 users have noticed, there is a shortage of Lightning cables. Because of the significantly smaller size compared to the legacy 30-pin dock connector, manufacturing yield rates have been decreased.
Apple’s site lists a shipping time of 2-3 weeks, but the cables are apparently in stock at most Apple Stores.