Watch for analog *sound* technologies to reappear!

Wired 11.03: Start
[snipped all but this]

   START b.f.d.

   Why Analog Is Cool Again

   Super-sensitive switches etched in silicon? This is not your father's
   solid state.

   By Paul Boutin

   Sharp, vibrant, incredibly detailed: The pictures produced by Foveon's
   X3 image sensor chip are seductive evidence that pixels will displace
   film. The Sigma SD9 - the first commercial camera to use Foveon's
   technology - captures three times more color per pixel than standard
   digital shooters. But here's the thing: This isn't digital technology.
   It's a twist on old-fashioned analog electronics - an array of
   millions of light filters and detectors etched in silicon.

   Weird as it sounds, the road to smaller, cheaper, more
   energy-efficient consumer electronics may be paved with analog
   technology. These circuits are built from the same components as their
   digital counterparts but suck 90 percent less battery power. The
   difference? In an analog device, each transistor acts like a dial,
   with a wide range of readings that depend on the sinuous fluctuation
   of voltage, current, amplitude, and frequency. Digital circuits, on
   the other hand, use the same transistors as simple on-off toggle
   switches. Analog transistors capture far more information, so you need
   fewer of them.

   Advances in the digital realm are powering the technology. Tiny analog
   circuits, sensors, and even radios can be manufactured using the same
   fabrication techniques - microscopic etching on semiconductor wafers -
   that have kept Moore's law chugging along. Devices with analog chips
   in their guts will begin landing in consumers' hands this year in the
   form of high resolution cameras and mobile phones that can go a week
   without recharging.

   Much of the new analog circuitry creeping into consumer gadgets
   springs from the research of Carver Mead, Foveon's founder and chair.
   As a Caltech professor (now emeritus) in the 1970s, Mead sought to
   imitate the analog elegance of the human brain. In 1986, Mead
   cofounded a company, Synaptics, to build high-performance analog
   computers. He understood that solid state circuitry would be ideal for
   connecting computers to the real world of light, touch, and sound,
   which are analog by nature. Synaptics eventually focused on the
   tactile, becoming the leader in laptop touchpads. (It controls about
   80 percent of that market.)

   Next came Foveon, founded in 1997. Its X3 image sensor chip is perhaps
   the most impressive analog electronics application so far. Standard
   digital cameras use filters that permit light sensors to capture only
   one primary color per pixel. From there, a signal processor runs
   algorithms that approximate the missing colors by sampling nearby
   pixels. That guessing game introduces telltale lines and whorls into
   the final picture. Foveon found a way to use standard silicon as an
   analog color separator. One of the optical properties of silicon is
   that different wavelengths of light penetrate it to different depths.
   This allows Foveon chips to stack red, green, and blue sensors at
   every pixel.

   Impinj, another Mead startup, hopes to conquer sound with a technology
   that lets digital logic fine-tune a cell phone's analog transmitter
   midcall, so the overall circuit can be smaller. Impinj claims the
   design draws one-tenth the power of its two-part predecessors. It also
   puts out a more efficient signal, allowing phone networks to carry
   greater call volume. It costs less, too.

   For Foveon chief scientist Dick Lyon, who toiled for decades in the
   shadow of the Digital Revolution, there's a sweet payback to sculpting
   analog parts from silicon: "If you do it right, you can make
   transistors and create devices no one imagined."

   Paul Boutin ([log in to unmask]) wrote about CD-R swapping in Wired