An integrated low-power asynchronous epileptic seizure detector

In this paper, we present a new asynchronous seizure detector that is part of an implantable integrated device intended to identify onset seizure and trigger focal treatment to block seizure progression. The proposed system eliminates the unnecessary clock gating during normal neural activity monitoring mode and reduces the total power consumption. The proposed detector includes analog and digital building blocks with a variable time frame and four concurrent variable voltage window detectors to extract seizure onset information. The algorithm is validated in Matlab and the system is implemented in standard 0.13 μm CMOS process. Based on post-layout simulation results, the input referred noise of bioamplifier and the total power consumption of system are 4.4 μVrms and 7.1 μW, respectively. An accurate detection is achieved and no false alarms are recorded during analyzing the iEEG signals of two patients. The average detection delay of 9.5 sec is obtained after seizure onset.