Design of logarithmic current amplifier for micro-PCR EC detection

A Logarithmic Current Mode Amplifier (LGCMA) is designed and verified by 0.5 μm process aiming at electrochemical signal detection in the miniaturized polymerase chain reaction (μPCR) chip for the quantitative analysis of deoxyribonucleic acid (DNA) concentration. Fully electronic integrated front end detection system is concepted to readout electrochemical signal using the LGCMA as a pre-amplifier. This paper has a insight to the stability, logarithmic property, bandwidth and dynamic range (DR) and noise level of the LGCMA. The post simulation result shows the operation current ranges six orders of magnitude from 5 pA to 5 μA. Considering that noise presented in the circuits the minimum current resolution is InA.