Over at Real World Technologies, David Kanter writes that Intel’s research on Near-Threshold Voltage (NTV) is particularly interesting because it promises a path to continue scaling voltage and decreasing dynamic power. At ISSCC 2012, the company demonstrated a full x86 microprocessor (Claremont) that consumed as little as 2mW and could run off a solar panel.
The goal of NTV techniques is to enable extremely low supply voltages, by using circuits that are extremely robust; tolerating variability and resilient against errors. While this sounds quite challenging, it is eminently feasible. Consider the problem of dI/dt, where a sudden demand for current (e.g. a floating point unit that wakes up and starts executing) causes voltage to drop across the chip. Chips using NTV tend to use less power, meaning that the current consumed is much smaller. Moreover, NTV circuits at low voltage will run at lower frequencies, meaning that the supply has more time to stabilize before errors start to occur.