Sources: Apple , , AllThingsD
quote: People keep asking why Apple didn’t opt for the micro-USB connector. The answer is simple: that connector isn’t smart enough. It has only 5 pins: +5V, Ground, 2 digital data pins, and a sense pin, so most of the dock connector functions wouldn’t work – only charging and syncing would. Also, the pins are so small that no current plug/connector manufacturer allows the 2A needed for iPad charging.This takes us back to the sensing circuitry referred to. If one of the pins is reserved for sensing – even if it is the “dumb” sensing type that Apple has used in the previous generation, using resistors to ground – and two pins are mapped directly to the 2 USB data pins, the other 5 pins can be switched at will to whatever function is necessary. For instance, if the USB-to-Lightning cable is used, the data pins can signal whether the USB side is plugged to a charger or to a computer’s USB port, and the other 5 pins can be used for charging current without overloading any single pin.This also explains the size (and price) of the Lightning-to-30 pin adapter. It has to demultiplex the new digital signals and generate most of the old 30-pin signals, including audio and serial transmit and receive.
quote: Apple’s choices came down to:Stick with the existing 30-pin port, despite it being old, ugly, and so thick that it had become the limiting factor for how thin and small devices could be.Switch to an industry standard that, though small, was not as elegant or well-designed as what Apple could do on its own, and would cost Apple its control over the peripheral market. (And we’d still need dongles for existing 30-pin peripherals.)Invent something new and proprietary that looks and works exactly how Apple wants it to.If you think Apple spent much time pondering anything but the third option, you don’t understand Apple. ?