Dropped calls plague iPhone 3G, and not just in U.S.

ByLeslie Cauley and Michelle Kessler, USA TODAY

— -- If you're having problems with dropped calls on your new 3G Apple iPhone, you're not alone.

From New York to Stockholm, 3G iPhone owners are complaining loudly about connection failures — sometimes repeatedly — during calls.

The problem typically occurs when the device attempts to move from 3G to another network.

According to people familiar with the matter, the culprit appears to be the 3G chipset provided by Infineon Technologies, a German chipmaker. Sources declined to be identified because they are not authorized to talk about the problem publicly.

According to these sources, AT&T and Apple are working on a software fix. The fix, which will be available remotely via iTunes, could be ready as early as next week, they said.

Infineon "chipsets" — a group of chips designed to work together — allow the iPhone to jump from one network to another. The handoff is supposed to be seamless.

The dropped-call problem is global, says Roger Entner, senior vice president at Nielsen IAG.

"Apple has had the same problem in every market where the (3G) iPhone is sold," he says.

Translation: AT&T's 3G network isn't to blame.

"It's probably the device," Entner says.

The iPhone is sold in more than 20 countries, including Italy, France and Finland. New markets are added constantly.

Apple declined to comment.

Infineon did not respond to e-mail and phone inquiries seeking comment.

AT&T spokesman Mark Siegel declined to say whether the chipset was a problem, saying only that the 3G device "overall is working great."

Siegel says AT&T, as a matter of routine, urges iPhone users to sync often to ensure that they have the latest software.

Francis Sideco, a senior wireless chip analyst at semiconductor researcher iSuppli, says the problem could be in the Infineon chip or it could be something else.

Given the complexity of the iPhone — it's basically a miniature computer — the possibilities are endless. "It could be something as simple as a solder joint," he says.

Cellphones use many components to turn a person's voice into a digital computer signal and transmit it over a network.

These components are typically manufactured by different suppliers, then cobbled together on a circuit board in a factory.

Chipsets are usually subjected to rigorous testing prior to shipping. But Sideco says chips can get damaged in the manufacturing process or in transit.

The good news, he says, is that big carriers such as AT&T have testing equipment that can identify dropped calls and pinpoint the manufacturer of the failed part.

The bad news: If a simple software fix isn't feasible, Apple could be forced to issue a worldwide recall. Such a step would be costly and time-consuming.

It would also leave Apple, inevitably, with a prominent black eye, Entner says.

That said, Entner doesn't think it will come to that.

"In all likelihood, they won't have to do a product recall," he says, adding, "It depends how big the problem is."

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