A 1-MS/s 64-Channel Data Acquisition System With Full-Scale Input Range for Area-Sensitive Application Achieved 165.3-dB FoMS/Ch

Abstract

This article presents a novel data acquisition system (DAS) designed for area-sensitive applications, including automotive instrumentation, launch vehicles, and satellites, which require efficient area utilization and full-swing input/output capabilities for diverse sensors. Traditional approaches to achieving full swing, such as using CMOS input transistors or generating negative voltage via charge pumps, either result in high harmonic distortion (HD) or complicate chip design. To address these challenges, we propose a complementary analog front-end (CAFE) that shifts the input signal by a fixed voltage, enabling operation in a more linear region while employing feedback to minimize HD. The system incorporates two analog-to-digital converters (ADCs) that convert the input signal and subtract the digital output of the common mode voltage ( $V_{\text {CM}}$ ), facilitating effective data fusion for complete AD conversion. Fabricated using a 180-nm 1P5M BCD process, the DAS consumes 118.81 mW from a 5.0-V power supply, providing 64 channels in a compact area of $4.0\times 3.2$ mm. At a sampling rate of 1 MS/s, it achieves an effective number of bits (ENoBs) of 13.16, with a power consumption of 1.856 mW per channel and a dynamic range of 83.3 dB, resulting in an impressive figure of merit per channel (FoMS/Ch) of 165.3 dB.