Moving implant, body nets advance at ISSCC

Better body area nets
Alan Wong, head of IC design for Toumaz, described an 130 nm transceiver that implemented both IEEE 802.15.6 and Bluetooth Low Energy (BLE) radios for a wireless body area network (BAN).

The chip consumed less than 10 milliwatts in receive or transmit modes. The device was one of the first to implement the 802.15.6 standard expected to be formally ratified as a standard in the next few weeks.

Toumaz is about to launch a commercial BAN patch based on its own proprietary low power network using a chip designed three years ago. Following extensive field trials, it got U.S. regulatory approval for the disposable patch late last year.

The new chip is a prototype aimed at demonstrating to medical OEMs and hospitals the potential of standards-based BANs. Wong said consumer devices are expected to adopt BLE or Zigbee while hospitals are more likely to use 802.15.6, in part because it supports data streaming.

The networks could automate tracking of a wide variety of sensors used to monitor patients. “The technology still needs to be proven in commercial use, so we think the first year of sales will be quite slow, but this saves hospitals money and nursing resources,” said Wong.

Texas Instruments and Zarlink are among the other chip makers expected to pursue the opportunity for large medical OEMs such as GE and Philips.

Separately, researchers from the universities of Washington and Virginia showed a wireless sensor node using the 400 MHz medical band that could harvest up to 100 microwatts from human body temperature.

The device included an analog-front end and signal processing blocks to handle ECG, EEG and EMG signals. The 130 nm chip measured 2.5 x 3.3 mm, ran at levels down to 0.3V and consumed just 19 microwatts thanks to ultra low power blocks throughout the design.