to create the best technology, it’s better to be lucky
Founder and Chief Technical Officer Mike Muller explains how serendipity combined with the power constraints of a battery has led to ARM developing smart, low-power processors that are now suitable for a broadening range of consumer electronics.
The original ARM processor was developed for a low-cost computer in the late 1980’s. You make a chip low- cost by designing the processor with the least number of transistors to keep the chip small and with high software code density to reduce the amount of memory needed. Both of these characteristics have the added bonus of making the chip very low-power. When I presented our new technology at the Microprocessor Forum in 1992 an engineer from Texas Instruments was in the audience and was looking for a smart and low- power processor for applications from automotive to mobile phones.
Mobile phones have always been very sensitive to the power used by every component within the phone. However, consumers and operators want smarter mobile devices without compromising battery life. ARM has worked closely with semiconductor manufacturers, OEMs and service providers to get the correct balance between:
P - Performance of the processor required to deliver the desired functionality and capability.
P - Power consumed by the chip, both during peak operation and when idle.
A - Area of silicon, which equates to the eventual cost of the chip.
Getting the PPA balance right has been the key to ARM’s success in mobile, but has become just as important in other applications:
- •Mobile computers, such as tablets, need advanced processors that can browse the internet but have similar power constraints as mobile phones.
- •Microcontroller chips in washing machines and toys are very cost sensitive, each costing less than $1 each, but still need to be smart.
- •Servers consume huge amounts of energy. Some of our Partners are working on ARM technology-based chips which they believe can reduce energy by more than half.
Building smart, low-power computers is getting harder. Shrinking geometries used to bring smaller size, faster speed and lower power but below 65nm designers have to work much harder to balance the PPA equation. This requires the type of ongoing innovation that has always driven our business.
- •We have introduced techniques for running separate areas of an ARM processor at different frequencies and voltages reducing dynamic power consumption, and even shutting down part of the processor when they are not being used to further reduce power.
- •ARM’s advanced processors are now combined with optimised physical IP to deliver a predetermined PPA for a particular processor/process combination. This improves performance, lowers power consumption and reduces time to market for our Partners.
Getting the PPA balance right is unlikely to get easier, but every problem is an opportunity. We are now developing new technologies to manage process variability across an individual chip to further save power and increase performance. Each innovation we create makes ARM technology increasingly attractive to a wider number of semiconductor companies who are having to battle increasing cost and complexity in their chips.