Integrated constant voltage constant current readout interfacing circuit for EGFET electrochemical sensing

Integrated constant voltage constant current (CVCC) readout interfacing for EGFET electrochemical sensing is presented. Development of integrated CVCC readout circuit is lead to single chip smart sensor system with the low cost production. CVCC technique is commonly used in investigation of ionic activities solution. The design architecture of CVCC has been targeted to Silterra 0.13um technology with the size of area include the IO pads design is 873μm × 811μm. the functionality of sub modules in this design included the three stage operational amplifier, current source and voltage reference circuit have been proved via the simulation results. Furthermore, the minimum input voltage from the ion sensing membrane for this readout circuit is approximately 0.73V.