It was Apple Inc. (Nasdaq: AAPL)'s components suppliers that were responsible for leaking confirmation of a September debut for the thinner, lighter iPhone 5 (or 4S). But what will those components be, and which companies will make their way into the guts of the handset?

Light Reading sister company UBM TechInsights has been doing extensive iPhone investigating -- delving into previous design wins and market technology trends -- and believes, among other things, the next version will feature a Qualcomm Inc. (Nasdaq: QCOM) baseband chip for CDMA and GSM connectivity, a Broadcom Corp. (Nasdaq: BRCM) component and a much simpler system integration design.

And, sources tell The Wall Street Journal that Apple has already ordered these key components for its new iPhone.

Here's a look at what else TechInsights expects was on Apple's order:

Baseband Chipset: Most have given up hope of Long Term Evolution (LTE) support in the phone, but if Qualcomm is the chip supplier with its MDM6600, there's a good chance one model will at least be compatible with both AT&T Inc. (NYSE: T) and Verizon Wireless HSPA+ and 3G CDMA network, respectively. Most expect both carriers to get the device at the same time this year. (See Qualcomm Not Holding Up LTE iPhone and New Networks Hint at an iPhone 5 Timeline.)

Qualcomm's win in the phone is not a given, however. Steve Bitton, TechInsight's senior technology analyst, points out that while a universal phone would make the most sense, Apple did opt for the old Infineon Technologies AG (NYSE/Frankfurt: IFX) (now owned by Intel Corp. (Nasdaq: INTC)) chip in the GSM iPad 2. For this reason, it might make sense for Apple to move to a newer, forward-compatible HSPA+ chip made by Infineon.

Processor: It's fairly certain that Apple's own dual-core processor, the A5, will power the iPhone 5, but it's less clear which company will manufacture it. Many have speculated that Apple will move to a smaller 28-nanometer (nm) manufacturing process from Taiwan Semiconductor Manufacturing Co. (TSMC) (NYSE: TSM). Bitton says, however, that it's more likely to stick with Samsung Corp. 's 45nm processor, which it used in the iPad 2.

The two companies have been warring in the courtrooms over patent infringement allegations, but Bitton says TSMC's difficulty ramping up to 28nm may make Apple reconsider. (See Samsung Tries to Block Apple Sales in the US, Apple Sues Samsung for iCopying and Apple Escalates Samsung Lawsuit.)

Connectivity: Alongside Qualcomm's chip will be the Broadcom BCM4330 for Wi-Fi, Bluetooth and FM connectivity, Bitton predicts.

Accelerometer and Gyroscope: It's not all a new-parts party for the iPhone 5. TechInsights believes that Apple will stick with the same accelerometer and gyroscope combo from ST Microelectronics that it used in the fourth version of the handset. Camera: The camera image sensor will also come from an old supplier, OmniVision Technologies Inc. (Nasdaq: OVTI), but the company will debut a new sensor for the phone just as they did on the iPhone 4. This time, it will be powering an 8-megapixel camera too. Bitton doesn't expect OmniVision competitor Sony Corp. (NYSE: SNE) to be a second source for Apple as some reports have suggested.

Display: Apple has recently filed patents around OLED touch screens, which could suggest iPhone 5 will include a larger, sharper display, also improving visibility in sunlight and reduced power consumption.

Production: The biggest question mark for TechInsights is around the system integration and mechanical design of the new phone. David Carey, VP of technical intelligence at the company, writes that the heritage of the iPhone’s design has been very pretty, but often quite complex, relying on low-cost human capital. Carey writes:

— Sarah Reedy, Senior Reporter, Light Reading Mobile