Integrated Circuits and Systems for a Fully-Flexible Wireless Ambulatory EEG Monitoring and Diagnostics Headband

This thesis presents the design, development, and experimental characterization of wireless integrated circuits and systems built for ambulatory electroencephalography (EEG) monitoring and diagnostics. Two prototypes are presented.

The first one is a 3x4 mm2 integrated circuit (IC), designed and fabricated in a 130nm CMOS technology, and integrates eight recording channels. A novel analog circuit is employed in each channel that detects and removes motion artifacts during amplification, resulting in a clean EEG prior to digitization. The idea prevents the amplifier saturation and removes the need for post processing of the digitized signals using artifact pattern recognition algorithms.

The second prototype is an integrated system in the form of a fully-flexible wearable wireless medical device. It integrates eight motion-resilient, active-electrode recording channels, with inter-digitated non-contact electrodes embedded into each of them, all implemented on a 4-layer polyimide flexible substrate, yielding the smallest form factor reported for a wearable EEG device. The flexible main board is connected to a 13x17 mm2 rigid printed circuit board that hosts a low-power FPGA and a BLE 5.0 transceiver, which add diagnostic capability and wireless operation features to the device, respectively. The entire wearable solution with the battery weighs 9.2 grams.