A Low Noise Current Readout with 124 dB Dynamic Range for Bioluminescence Sensing

This paper presents a lower-power photocurrent measurement system for biomolecule quantification. The designed readout comprises a proposed capacitive feedback transimpedance amplifier (C-TIA) in conjunction with an asynchronous flip switch and a self-timed reset network followed by a reconfigurable time-domain quantization scheme. Unlike conventional C-TIAs, this readout provides frequency output without requiring an external clock to perform a periodic reset. Fabricated in a standard 180 nm CMOS process, the readout achieves a current measurement range of 124 dB spanning from $2 \mathrm{pA} \sim 3.5 \mu \mathrm{~A}$, a 98.3% linearity, and a 1 pArms input-referred noise, while consuming only $378 \mu \mathrm{~W}$. In vitro NanoLuc (NLuc) luciferase-based bioluminescence sensing for biomolecule quantification is demonstrated using this chip.