ICs poised to get under your skin

In the near future, patients equipped with wireless wearable sensors will receive regular checkup re- ports from their doctors without having to visit a hospital, Hyung Kyu Lim, chief executive of the Samsung Advanced Institute of Technology, said in an ISSCC keynote. "Health care devices and service robots are prime examples of emerging consumer products for such new services," said Lim. "However, the system complexity and implementation of these future services will be costly due to the high level of machine intelligence required." For example, startup Toumaz Technology (Abingdon, England) described at ISSCC a custom chip designed to power a wireless monitor that could be worn on a disposable patch. The chip is one of an emerging group of smart wearable devices that help patients and consumers get medical monitoring from the comfort of home. "We not only have an aging society, but one that does not have a healthy lifestyle," said Alison Burdett, director of technology for Toumaz. "There are increasing numbers of people with chronic ailments, and that's putting an enormous burden on health care systems worldwide." A large U.S. health care company is said to be working with Toumaz, aiming to field the silicon-backed patches in a hospital setting before the end of 2009. Companies including GE and Philips are reported to have similar projects in the lab. To keep power down and reliability up, Toumaz developed custom hardware and protocols for the 800- to 900-MHz wireless network the devices use at data rates up to 50 kbits/second. The chip draws 2.5 milliamps when communicating, but its digital control portion dissipates just 100 microwatts. "A custom media-access controller is crucial, because in short-range communications there is always interference, and we have many layers of mitigation," Burdett said. Despite the custom design, the active patch is expected to cost as little as $5 when it hits the market next year. The chip, which measures 16 mm2, will account for a small fraction of that cost. It will be made in a 130-nanometer process by Infineon Technologies.