DoE funds energy-efficient chip effort

PORTLAND, Ore.—The U.S. Department of Energy (DoE) has awarded Columbia University $2.8 million in Recovery Act economic stimulus funding to design power converters that efficiently regulate voltage for multi-core processors right on the chip, which could save U.S. data centers billions of kilowatts of energy yearly.

IBM Research and Cornell University will also participate in the program to design on-chip voltage regulator modules using advanced magnetic induction methods.

"What we want to do is bring power onto chips at a higher voltage and down-convert it on the IC itself," said project leader Kenneth Shepard, a professor of electrical engineering at Columbia. "In a multicore processor you are also going to want different cores to operate at different supply voltages. So if you have 128 cores you'll want 128 regulators, which is why we want to do it on the chip."

Voltage regulator modules today are separate chips on the mother board that regulate voltage by working from a reservoir of energy stored in capacitors. The Columbia team, however, thinks that on-chip regulators will work better using inductors as the energy reservoir, which requires magnetic materials to achieve the kind of energy density required.

"To get enough energy density from inductors, you need to employ magnetic materials," said Shepard. "Which is why, for this DoE grant, we needed to bring in materials experts from IBM Research and Cornell University to help us design inductor structures with enough density to provide the energy storage we need with inductors that will fit on an IC."

The two year program, using $2.5 million in stimulus funding matched by $280,000 from the State of New York, is one of 14 recent DoE grants whose aim is to improve the energy efficiency of communications- and information-technology. The DoE estimates that U.S. data centers consumer more that 50 billion kilowatt-hours per year, enabling on-chip voltage regulator modules to reap billions of kilowatt-hours in energy savings from even from a modest 10 percent increase in efficiency.