Nikas, A.A.NikasJambunathan, S.S.JambunathanKlein, L.L.KleinVoelker, M.M.VoelkerOrtmanns, M.M.Ortmanns2022-03-142022-03-142018https://publica.fraunhofer.de/handle/publica/40725910.1109/BIOCAS.2018.8584687In this paper an architecture for a continuous time sigma delta modulator used in a neural recording channel is proposed. The instrumentation amplifier based input structure of the converter exhibits a high input impedance and linear behavior. Properties making its use interesting in analog frontends for direct application on sensor elements. Circuit linearity is achieved solely by negative feedback. A prototype was developed as a 2 nd order single bit modulator in a cascade of integrators feedforward form and was taped-out in a 180nm technology. Simulations show an input impedance of >1GO and a THD of 0.012%. The input referred noise is 2.2mV at an average current consumption of 14mA occupying an area of 0.07mm2.en621006conference paper