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3G Cell Data iPhone Now Feasible

Apple CEO Steve Jobs justified the iPhone’s use of so-called 2.5G cell data technology – technology that fills the gap between the very slow second-generation (2G) and relatively fast third-generation (3G) specifications – by noting that 3G chips with the low power consumption and small form factor needed for the innovative phone were perhaps a year away. A year turned into months last week.

Broadcom, a long-time Apple Wi-Fi chip partner alongside its arch competitor Atheros, let slip the veil on its advanced, integrated 3G chip for GSM networks, such as those run by AT&T, Apple’s iPhone partner, as well as most of cellular carriers in Europe and the rest of the world.

The euphoniously named BCM21551 3G Phone on a Chip combines the highest current data rates for both upstream and downstream High-Speed Packet Access (HSPA, often called HSDPA, with D standing for Downlink, because of the downstream focus). The chip is built on a single 65 nanometer die, the smallest current chip scale; 65 nanometer refers to the smallest possible circuit path. The smaller the die, the less power consumed, the less heat generated, and the less space taken up by circuits, which leads to smaller chips relative to what tasks they perform. Comparable HSPA systems use 90 nanometer or larger processes that result in larger chips or require two or more chips to achieve the same functions. Broadcom is using CMOS (complementary metal-oxide-semiconductor) technology for the chips, which is the cheapest way to make integrated circuits.

Although AT&T’s 3G network operates at just 3.6 Mbps and isn’t fully deployed in the United States, European carriers are already using the next flavor that offers 7.2 Mbps downstream and upstream rates that will eventually reach 5.8 Mbps. These are raw data rates shared among users; typical average rates run about 15 to 20 percent of the raw rate.

Broadcom calls their new product a 3G Phone on a Chip, because it includes not just the 3G cell data technology, but two ARM11 processors, which are widely used in handhelds and mobile devices. An ARM processor is on the iPhone’s main logic board.

The Broadcom chip also includes Bluetooth 2.1+EDR, support for 30-frames-per-second video output, an FM radio receiver, an FM radio transmitter (for car stereo playback), and processing for a camera with up to 5-megapixel resolution. A host of other hooks enable low-power output to an LCD display, stereo music with five-band equalization, full speed USB 2.0, and – unless I misread the press release – a built-in trouser press that can handle jeans and khakis.

The chip is shipping in small quantities now – called “sampling” – to Broadcom’s best customers. The price in quantity will be $23 per chip when it ships, at a date not yet announced, but which is typically a range of 3 to 6 months following sampling in the chip industry.

A good half-dozen companies in addition to Broadcom and Atheros compete for cellular and wireless networking equipment manufacturing deals, and thus it’s likely that other chipmakers will make similar announcements within three months.

The ready availability of Broadcom’s 3G Phone on a Chip could mean a Q2 2008 announcement from Apple of a significantly revised iPhone, with support for 3G data, a 5-megapixel camera, and video conferencing, to note just a few of the iPhone’s features that could use improvement and that require hardware support (I want a To Do application as well, but that’s just software.)

This is, of course, pure speculation, but given Steve Jobs’s comment about needing a better chip to enable 3G, you have to assume that Apple has been talking to Broadcom and other chipmakers about the chips necessary to power the second-generation iPhone.

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