Low-power CMOS-based epileptic seizure onset detector

In this paper, we present an implantable CMOS integrated device that automatically detects epileptic seizure onsets. By recognizing partial-onset seizures, it can improve epilepsy treatment. The circuit consists of a chopper stabilized preamplifier, comprising a modulator, an amplifier, a high-pass filter with low cut-off frequency, and a voltage span detector. The proposed low-power detector extracts seizure onset information from neural signals and monitors the signals over a time period to capture seizure events. Signals are analyzed and the mathematical model is validated in Matlab. Circuits are implemented in a CMOS 0.18-µm process. Total power consumption of the preamplifier and detector are 6.72 uW and 55.51 nW, respectively. Detection performance was verified using intracerebral electroencephalographic recordings from epileptic patients, and the detector accurately identified seizure onsets.