By using an Ion Beam Etcher, it's possible to take layers off a semiconductor and analyse how it's made. So that's what iFixit did, in conjunction with Chipworks. Here are some of the main discoveries:
- First, a biggy: "We have confirmed through early analysis that the device is fabricated at Samsung's Foundry. We suspect we will see Samsung's 28 nm Hi K metal Gate (HKMG) being used."
- The distance between each of the chip's transistors is 114 nm, compared to the A6′s 123 nm.
- That 9 nm difference — from a 28 nm process to a 32 nm process — means the same computational power can be squeezed into just 77 per cent of the original area. But given the A7 is larger than the A6, it's clear where all that poke came from.
- In total, the A7 packs one billion plus transistors onto a 102 square millimetre field.
- Chipworks claims that the M7 section of the silicon is an NXP LPC18A1 — part of the LPC1800 series of high-performing ARM Cortex-M3 based microcontrollers.
- In fact, the M7 packs accelerometer, gyroscope, and magnetometer, and does some fancy maths before neatly passing orientation data to the main chip.
- The Wi-Fi module is exactly the same as that in the iPhone 5.
- The 4G LTE modem uses two chips: a Samsung-fabricated LTE baseband processor and a Samsung DRAM module to retain carrier specific information.