Mobiles take a great leap forward

Moore's Law dictates that chips will shrink and get more powerful

By Mark Ward Technology Correspondent, BBC News website

Technology legend Gordon Moore may have been working at Intel when he thought up the law that bears his name, but it applies to any and every microprocessor.

Be the chip inside a PC, or mobile phone, the logic of Moore's Law dictates that they will get progressively more powerful thanks to the inexorable progress of the semiconductor industry.

This has led the PC through successive generations - 286, 386, 486, Pentium - and now mobile handsets are about to embark on a generational shift of their own.

More than 80% of the chips inside mobile phones are designed by UK firm Advanced Risc Machines (Arm) and the most versatile phones of 2008, such as Apple's iPhone 3G, have one or more Arm 11 processing cores onboard.

The Arm 11 series debuted in 2003 and now, five years later, the phones and the applications they run are starting to stretch it to the limit.

Rob Coombs, a spokesman for Arm, said the Arm 11 was roughly 11 times the processing power of the Arm 7 chip that debuted in 1993 and is still used today in the most basic phones.

But now, said Mr Coombs, the Arm 11 family is starting to make way for the Cortex range of processors. He claims the Cortex A9 series will have 30-100 times the processing power of those 1993 era chips.

Power plant

The first devices based around the Cortex A9 chips have started to appear. Towards the end of 2008, Archos released the A5 and A7 media tablets. These use a 5- or 7-inch touch-screen that gives an owner access to movies, games and web surfing.

While Cortex A8 processors are found in some phones all have a single-processing core. By contrast, all the chips in the Cortex A9 family are multi-core processors.

The Archos A5 and A7 are the first products to use the Cortex A9 chips

"There are two main advantages to the multi-core approach," said Richard Bramley, manager of architecture activities at chip firm ST NXP Wireless. "Head room and power consumption."

"It's a way to keep going with Moore's Law when you are running out of clock speed," he said. "The other big advantage everyone sees for multi-processing in mobile is power consumption."

"You're able to do much more on one battery charge," he said. "That's very visible to the user."

Multiple cores inside a mobile make it possible to use lower voltages to get roughly the same amount of work done. Instead of one chip running flat out to get a job done two can work half as hard. The advantage is, said Mr Bramley, that the chip runs at a lower temperature.

"A cooler device means a lower clock speed and lower leakage," he said.

Having multiple processing cores should also mean that devices powered by them are much more responsive, said Mr Bramley.

With only a single processor, one job has to complete before another can get started. By contrast with a multi-core chip jobs can be run in parallel. "You can improve real time performance," he said.

Mark Frankel, vice president of strategic marketing at mobile firm Qualcomm, said because Arm chips came from the mobile world they were quite modest in their power consumption.

Multi-core chips would likely extend this and perhaps mean that a device could run all day but let a user do many of the tasks familiar from low-end laptops.

"We see power differences in the several times range between [Intel] X86 and Arm architecture when these devices are in active mode," said Mr Frankel.

"More importantly in standby and sleep modes in X86 you are drawing ten times more power than an inactive state," he said.

Future fun

Many have tried, and failed, to make a portable media device

Brian Carlson, strategic marketing manager at TI, said the advent of Cortex A9 chips would change the way that people thought of what are now known as smartphones.

While gadgets such as the Apple iPhone, Google G1 and Nokia N97 are very versatile they still force people to endure delay while they surf the web, read e-mail or use other applications.

"When you do web browsing on your laptop that's the kind of response times you come to expect," said Mr Carlson.

The greater processing power of the Cortex A9 chips will make any device using them a candidate to take on the netbooks - small web-enabled devices that are currently proving so popular.

Taiwanese firm Asus has led the companies producing netbooks with its Eee PC range of machines. But companies such as Dell, Intel and many others are also now producing small, web-enabled computers - fierce competition for Arm as it enters this market. Intel in particular is targeting the mobile market with its Atom processor.

Whoever dominates the future of the net-connected, voice-capable computer market, all these portable machines will have a great deal more computer power under the hood, said Mr Carlson.

"That," he said, "should enable a whole new class of applications."

For instance, said Mr Carlson, the computer power could be used to create a gesture recognition system that would watch a user's expression and navigate for them through a document, movie or music track depending on whether they were smiling or frowning.

He said: "You are going to be doing things with your phone you cannot imagine."