Design of Low Power Bio-Sensor Read-Out Circuit Schemes for Implantable Systems

This paper presents two low-power sensor read-out circuit schemes for implantable biosensor applications. The proposed work presents the design of ASK and FSK schemes in bulk CMOS technology. Either scheme consists of a data generator block and modulator block. The first version of the circuit is designed in a 0.35μm CMOS process and it can generate an amplitude-shift-keying (ASK) signal while consuming 400 μW of power with a 1.5-V power supply. The second version of the readout circuit is designed in a 0.5μm CMOS process and produces a frequencyshift-keying (FSK) signal while consuming 1.675 mW of power with a 2.5-V power supply. The prototype circuitries has potential applications in the monitoring of blood glucose level, lactate in the bloodstream, and pH or oxygen in a physiological system/ environment.