An integrated CMOS potentiostat for miniaturized electroanalytical instrumentation

Two major limiting factors in mass production and field use of electroanalytical instruments have been the size and cost of potentiostats. This monolithic CMOS potentiostat has performance comparable to bench-top instruments at a fraction of the size, power consumption and cost. A block diagram of the potentiostat chip is shown. An integrating DAC sets the voltage between the working electrode, where the electrochemical reactions of interest take place, and a chemically stable reference electrode. The control amplifier regulates this voltage using feedback to drive a third (counter) electrode. The working electrode current is measured with a current-input dual-slope ADC.<>