January 4, 2010 — University of Virginia engineering faculty members' prize-winning idea for a low-power, inexpensive portable electrocardiograph may one day make assessing a person's risk of heart attack as simple as wearing a small adhesive bandage.
Ben Calhoun, assistant professor of electrical engineering, and associate professor Travis Blalock, together with faculty and graduate students from the Charles L. Brown Department of Electrical and Computer Engineering and the Department of Computer Science, submitted an integrated circuit design in the Low Power Design Contest, sponsored by the International Symposium on Low Power Electronics and Design. At the 2009 symposium in San Francisco, judges awarded the paper first prize.
The paper describes a novel system-on-chip that acquires and processes an EKG signal for wireless monitoring of a patient's heart to determine whether the heart is beating normally.
"The real idea here is to reduce the size, weight and power consumption of current portable electrocardiogram monitors," said Calhoun, who heads the Robust Low Power Very Large Scale Integrated Circuits Group at U.Va.'s School of Engineering and Applied Science.
An existing monitor, for example, is the size of a hand-held tape recorder. It must be worn on a belt (even while the patient is sleeping), is connected to the patient's chest via a web of wires and electrodes, and can be powered for only 24 hours. By comparison, the Calhoun team's low-power EKG would provide the same functionality as the existing monitor, or better, but be small enough to be integrated into a small bandage or a piece of clothing.
What made their paper a winning entry, Calhoun said, is that it not only described state-of-the-art low-power technology, but it also incorporated on the same chip, for the first time, very low-power analog circuits alongside programmable digital microprocessors operating at sub-threshold.
The prize-winning chip was designed and built – under the supervision of Calhoun and Blalock – by electrical engineering graduate students Jonathan Bolus and Stuart Wooters and 2009 electrical engineering graduate Steven Jocke, who now works for Lockheed. Computer science professor Alfred Weaver and his graduate student, Andrew Jurik, also credited on the paper, helped the engineers develop the back-end software and some of the code for the microprocessor.