Development of signal conditioning system for biosensor applications

Abstract

This signal conditioning circuit design is a micro-power, three terminal electrochemical cell amplifier that uses less than 1-μA total supply current for battery-powered or energy-harvested sensor applications. Electrochemical cells necessitate constant bias, which requires the amplifier circuit to be powered continuously to eliminate sensor start-up and settling times. The design is assembled on a dotted board compatible with the development Kit platform to allow testing with an MSP430 ultra-low-power processor to utilize the launchpad processor analog to digital converters (ADCs) and liquid crystal display (LCD) for stand-alone operation. The whole design consideration is done after taking into consideration of three-terminal screen printed electrode that can have several applications as verified by experimentations and results. The design canbe used for agricultural applications as a wide range of sensor current has been taken into design consideration. This needs simple modification based on sensitivity and response time of sensor.