iFixit

Did someone ask for a close-up of the Apple 338S1077 Cirrus audio codec?

What exactly does an audio codec do? In short, it's a single device that acts as both a digital-to-analog and analog-to-digital converter to properly encode and decode audio in and out signals.

Chips on a board. Kinda like ants on a log.

• STMicroelectronics LIS331DLH (2233/DSH/GFGHA) ultra low-power, high performance, three-axis linear accelerometer
• Texas Instruments 27C245I touch screen SoC
• Broadcom BCM5976 touchscreen controller

  • Rather than a single touchscreen controller, Apple went with a multi-chip solution to handle the larger screen size, à la iPad.
• Apple A6 application processor
• Qualcomm MDM9615M LTE modem
• Qualcomm RTR8600 Multi-band/mode RF transceiver, the same one found in the Samsung Galaxy S III

An iPhone with 4G connectivity? It's more likely than you think.

We can now confirm that the Qualcomm MDM9615M is the 4G LTE modem powering this new feature.

• After being teased for over a year by Android bullies, the iPhone faithful finally have 4G LTE on their side. What will they do with this newfound power? Only time will tell.

The Qualcomm MDM9615M is a 28 nm LTE (FDD and TDD), HSPA+, EV-DO Rev B, TD-SCDMA modem.

The MDM9615 allows for multi-spectrums, multi-mode LTE support. It is responsible for transmitting simultaneous voice and data transfer on LTE (provided the carrier has the infrastructure to allow simultaneous voice and data transfer.)

We also find the Qualcomm RTR8600 multi-band/mode RF transceiver. The RTR8600 is paired alongside the MDM9615 to support various bands, including 5 UMTS bands, and over 5 LTE and 4 EDGE bands.

Here's a closer look at the Broadcom BCM5976 trackpad controller.

Apple used this same chip in the MacBook Air to control the trackpad. Here, it's working together with the Texas Instruments touchscreen controller to take care of touch inputs on the Retina display.

After completely dissecting the logic board, we turn our attention back to the rear case.

Not even a healthy heap of adhesive can stand up to our mighty spudger!

The Lightning connector assembly, which includes the headphone jack, loudspeaker, and lower microphone, comes out next.

It appears that the Wi-Fi antenna is also embedded into the assembly. The iPhone 5 now includes support for 2.4 GHz and 5 Ghz.

• Antennas are sized to be fractions of full wavelengths, so the 1.23" of a quarter 2.4 GHz wave is close enough to the 1.18" of a half 5 GHz wave that a single antenna can serve both frequencies.

The first of three microphones comes out of the iPhone 5 along with the Lightning connector assembly.

It is safe to assume that the microphone located at the bottom front of the device is used for voice commands and voice calls.

The other two microphones remain in the device, for now, waiting towards the top of the phone.

The Lightning connector looks like it could be swallowed by the the 30-pin dock connector.

Here we can clearly see the eight leads in the new Lightning connector.

• While there hasn't been any official word on the pin-out for the Lightning connector, we can confidently say that two of them will be used for power and ground. As for the other six, well, that's anyone's guess.
• Update: We now know what the pin-out of the Lightning connector is.

Apple claims that the Lightning connector is all digital. However, they also claim that the iPhone 5 supports analog audio-out and VGA video, indicating that there may be some kind of digital-to-analog conversion going on inside the cable.

Further investigation into the Lightning connector shows a neat array of pins and a clip to hold the cable in place.

Each pin (shown in the third picture) is springy and gold plated on the end to ensure good conductivity between the Lightning cable and the socket.