An Asynchronous CMOS Current Readout With 124-dB Dynamic Range for Bioluminescence Sensing

Abstract

This letter presents a photocurrent readout for bioluminescence detection. The design incorporates an asynchronous architecture employing a proposed capacitive feedback transimpedance amplifier (C-TIA) with a self-timed reset network and an all-digital reconfigurable time-domain quantization scheme. It eliminates the need for a periodic reset signal required in conventional C-TIAs and offers a wide dynamic range (DR) of 124 dB, a nonlinearity of 1.7%, and a 1-pArms input-referred noise while drawing only $210~\mu $ A from a 1.8-V supply. Fabricated in a standard 180-nm CMOS technology, it occupies an area of 0.16 mm2. This design aims to facilitate in vitro NanoLuc (NLuc) luciferase-based bioluminescence sensing for biomolecule quantification at room temperature, with preliminary biological testing presented in this letter.