An Analog Front-End Circuit for CO2 Sensor Readout in 0.18-µm CMOS Process

• DOI: 10.1109/vlsi-dat.2019.8741403
• Publication Date: 2019-06-20T22:19:04Z
• Authors: Deng-Kai Lin; Chih-Chan Tu; Shih-Kai Kuo; Tsung-Hsien Lin
• Keywords: Analog front-end

An analog front-end (AFE) trans-impedance amplifier (TIA) for CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> detector is presented. It senses the current generated from IR detector, which contains information of concentration in air. automatic sensor baseline calibration loop proposed to cancel diode DC and amplify only desired signal. The prototype implemented 0.18-μm CMOS process. measurement performed with an off-chip resistor voltage input, emulating detector. consumes 3.38 mW (including calibration) 62.4-dB SNR over 1-kHz BW achieves 0.16 ppm resolution.