Speedy Chip Needs Far Less Juice
Mobile computing devices that need charging once a day would need it just once a month with a new type of chip that uses a thirtieth of the power of conventional chips and is seven times faster by virtue of underlying logic that embraces error in its calculations.
This combination of features makes these chips ideal for battery-powered devices and running applications that don't require 100% accuracy, according to researchers at Rice University who contributed to the technology.
For example, streaming video to a cell phone using one of these application specific integrated circuits (ASIC) would conserve battery life because of its low power consumption. It would be able to generate a sufficient video image as well, given the small size and low resolution of cell-phone screens in combination with humans' ability to fill in gaps in information that is provided from the screen, researchers say.
Using a thirtieth of the power means devices that now need charging every day would need it once a month instead.
Called probabilistic complementary metal-oxide semiconductor (PCMOS), the technology was developed by a team headed by Rice University Prof. Krishna Palem and Prof. Yeo Kiat Seng of Nanyang Technological University in Singapore. The chips were announced at the International Solid-State Circuits Conference (ISSCC) in San Francisco.
Rather than using the Boolean logic of traditional chips, it uses probabilistic logic that is less sensitive to the increased electrical noise generated within chips as they get smaller. The solution with traditional chips was to pump more power through the smaller chips so the signal could be heard over the noise. PCMOS chips use less power and the probabilistic logic takes into account errors that might be introduced by noise intermixed with signal, the researchers say.
So far the teams have made an ASIC dedicated to encryption, a suitable application because the chip logic generates the random numbers required by encryption algorithms.
The chips would be used to power specific tasks rather than performing as the CPU of a device such as a laptop, the researchers say. They would be used within video cards, medical scanners and electronic toys to process specific tasks.
"Our goal is green computing," Palem says. "We're looking for applications where PCMOS can deliver as well as or better than existing technology but with a fraction of the energy."
The chips could be on the market within four years, he says.
Palem said he hopes PCMOS technology will enter the embedded computing market in as little as four years.
The research was funded by the Defense Advanced Research Projects Agency and Intel.