A Chemoresistive Gas Sensor Readout Integrated Circuit with Sensor Offset Cancellation Technique

This study proposes a chemoresistive gas sensor readout integrated circuit (ROIC) with simple and effective scheme for tracking canceling the offset value. Before reading out sensor, proposed ROIC dynamically updates of analog-to-digital (A/D) reference range suitable to offset, enabling accurate A/D conversion within sensor’s dynamic (DR). Therefore, this approach eliminates need additional complex circuitry or compensation algorithms, allowing extract desired amount change effectively. As result, overall DR system is maximized. In addition, maintains compatibility existing environment while effectively alleviating physical limitations sensor. terms commercialization, effectiveness feasibility ROIC, based on single-slope converter structure as technique, have been verified. A prototype was fabricated employing 180-nm standard CMOS process, exhibiting total power consumption 0.5 mW rate 62.5 kSPS. The noise 1 Hz 2 kHz 10.1 μVRMS, corresponding 137 dB. Further, maximum integral non-linearity (INL) -72.24 minimizes scattering LSB full scale, enhancing performance in applications.