A low noise readout detector circuit for nano-ampere sensor applications

Abstract

A readout detector integrated circuit (IC) has been developed which is capable of detecting nano-ampere photo-current signals of interest in a high (micro-ampere) background illumination or DC noise level (SNR=92 dB). The readout detector sensor IC processes transient signals of interest from a separate photodiode pixel array chip. Low noise signal conditioning, filtering, and signal thresholding implement smart sensor detection of only "active pixels". This detector circuit can also be used to perform signal conditioning for other sensor applications that require detection of very small signals in a high background noise environment.