A Fast Current Sensing Front-End IC Design for Nanopore-Based DNA Sequencing

Abstract

This paper presents a fast sensing front-end integrated circuit for nanopore-based DNA sequencing. Single-stranded DNA passes through the nanopore on the cell membrane to generate an ultra-small current on the electrodes. Therefore, a trans-impedance amplifier and a voltage-to-time conversion circuit are designed and optimized in this work to realize the current detection. This front-end IC reduces the single base detection time to $\mathbf{10}\ \boldsymbol{\mu}\mathbf{s}$ at minimum. The whole circuit is implemented in 180-nm CMOS process. The results show that the implemented IC can detect the minimum current of 10 pA and can measure the current through nanopores ranging from 10 pA to 150 pA. Its power consumption is $\mathbf{42}.\mathbf{8}\ \boldsymbol{\mu}\mathbf{W}$, and the input reference noise of the input stage is 1.93 pV2/Hz.