Nanoelectronics research centre imec and Holst Centre have developed an ECG readout chip which uses time domain circuit techniques. According to the partners, the device offers consistent beat detection abilities and may pave the way for low cost, low power multisensor SoCs for wearable medical devices.
The chip, which has an area of 0.015mm2, is implemented in 40nm TSMC CMOS process. Consuming 3.3µW from a 0.6V supply, the device is said to handle an AC sigma of up to 40mVpp and DC electrode offset of up to 300mV.
Constant beat detection is supported by the ECG signal being acquired from the noise-stress database, meaning the system does not saturate. The time domain based readout architecture, said to take advantage of technology scaling, avoids the need for analogue circuitry. In imec’s opinion, current analogue circuit techniques don’t scale well enough and analogue front end readout chips face significant challenges in combining a large dynamic range with small size and low power consumption.
“Our breakthrough readout ECG chip paves the way to low cost, low power multisensory systems for ambulatory medical applications,” said Nick Van Helleputte, team leader biomedical circuits at imec. “Furthermore, it opens innovation paths for analogue front end design beyond 40nm, leveraging the power and area benefits of scaled technology in digital architectures.”
Author
Graham Pitcher
Source: www.newelectronics.co.uk