A high dynamic range ultralow-current-mode amplifier with pico-ampere sensitivity for biosensor applications

摘要

A novel ultralow-current-mode amplifier (ULCA) serving for on-chip biosensor signal pre-amplification in the integrated biosensing system (IBS) has been presented and verified in SMIC 0.18 μm CMOS technology by elaborately considering gain, bandwidth, noise, offset, and mismatch. The proposed ULCA solved the noise, bandwidth, and current headroom dilemma in the reported works, and can completely satisfy the specifications of IBS. It provides a current gain of 20 dB, 3 dB bandwidth of 7.03 kHz and input dynamic range of 20 bit, with only 1 nA of DC quiescent current, while the input offset current and noise current are less than 16.0 pA and 4.67 pArms, respectively. Keywords Integrated biosensing system (IBS) - Ultralow-current-mode amplifier (ULCA) - Subthreshold - Noise - Mismatch