Last year I bought some Intel (INTC) for its yield and longer term potential for growth. I thought it would eventually get the power equation right so that it could succeed in mobile. Thus far, I've been disappointed on the power progress. The current IEEE Spectrum magazine, however, pointed to some light at the end of the tunnel in a brief piece called "Six Paths to Longer Battery Life."
The article identified and explained what it believed were the six most relevant frontiers for reducing power. Intel was a leading factor in three. This is the first time we've seen Intel at the forefront of power tech since the company sold its ARM business to Marvel.
The Six Technologies
Near-Threshold Computing - operate chips close to minimum voltage to switch a transistor. Intel has a 32 nm Pentium-class processor that can operate with as little as 280 mV. The chip slows dramatically - at 450 mV it only runs at 100 MHz, but consumes only 1/5th the energy.
Razor-Thin Margins - is the idea that chips detect errors and can adjust operating voltage up and down on the fly. The University of Michigan and Harvey Mudd have demonstrated this with an ARM Cortex -M3.
Smaller Transistors - Intel's Ivy Bridge uses 1.4 billion 3-D transistors. These 22 nm chips have an operating voltage 200 mV less than the previous chips.
All-Digital Phase Locking - Historically phase-locked loops were analog components. Digital phase lock loops consume about 1/10th of the power and are easier to build. Intel showed a 22 nm part that consumes as little as 0.7 mw. Samsung's comparable, also digital part, consumes 2.5 mV.
Smart Converters - switched capacitors convert analog to digital. They consume a lot of power. A team at Oregon State substituted a loop of digital inverters to accomplish the same thing. Another team at National Chiao Tung University in Taiwan reduced power by working on signals in two stages rather than one.
Next Generation DRAM - DDR4 memory drops the supply voltage to 1.2V from 1.5 V. Samsung says to look for the parts in early 2013.
Disclosure: I am long INTC.