The device includes a system-on-chip (SoC) that is attached to a long-lasting, energy-efficient electrode patch. The patch measures physical activity, the heart’s electrical activity, and bioelectrical impedance monitoring, like body composition, repository activity, sleep apnea, and COPD.
Two electrodes are used to monitor these actions.
“The resulting voltage has an amplitude proportional to the impedance,” says imec. “It is measured at the other two electrodes along with the ECG signal.”
As body composition changes in fluid balance, composition, and lunch volume, bio-impedance changes with it. Specifically, the patch focuses on lung volume as changes can be seen in respiration rate and depth.
“The frequent at which we inject the current for bio-impedance measurements is well above the frequency content of the ECG signal,” according to imec.
All of the functions are integrated on the SoC.
“The SoC combines an unprecedented number of biomedical analog interfaces into a single chip, on-board digital signal processing, high fidelity operation, and multi-day monitoring capability with a single battery,” imec says.
Three ECG channels are integrated on the biomedical analog interface: photo-plethysmography (PPG), galvanic skin response (GSR), and two multi-frequency bio-impedance (BIO-Z) channels used to support stroke volume measurements, body fluid analysis, and three reconfigurable channels.
“imec and Holst Centre’s SoC combines advanced biomedical readouts, supported by an ARM Cortex M0+ controller and accelerators for sample-rate conversion, matrix processing, data compaction, and power management circuitry (PMIC),” says imec. “The PMIC operates from a battery source (2.9- 4.5V) and generates the required voltages for the readout IC. It supports dynamic voltage scaling optimized for, but not limited to, low power and high performance applications, and can be fully customized for specific healthcare applications.”
The health patch can be worn for long periods of time, including in the shower. It connects to a smartphone via Bluetooth and uses a cloud-platform. The chip can also connect to a computer via USB to store information.