The Phoenix chip's photovoltaic system requires 10 hours of indoor light or 1.5 hours of sunlight to fully charge the battery.

The chip's micro radio automatically tunes into whatever wireless frequency is available in order to download data to a reader. The data can then be used as part of an electronic medical record for treatment.

According to researchers, the micro computers and their wireless networks could one day also be used to track pollution, monitor structural integrity, perform surveillance, or make virtually any object smart and trackable. "Our work is unique in the sense that we're thinking about complete systems in which all the components are low-power and fit on the chip," Sylvester said. "We can collect data, store it and transmit it. The applications for systems of this size are endless."

The researchers presented their papers on the new microcomputers and the networks at the International Solid-State Circuits Conference (ISSCC) in San Francisco. The work is being led by three faculty members in the University of Michigan Department of Electrical Engineering and Computer Science.

University professor David Blaauw said that once the chips reach the nanoscale level, hundreds of the computers could be fitted onto a single silicon wafer to perform multiple monitoring tasks.