1 / 2023-05-22 10:33:19

A High-Precision CMOS Voltage Reference with Curvature Compensated Bandgap for Fluorescence Detection Chip

Bandgap reference, High-order curvature compensation, Temperature coefficient, Low dropout linear regulator

A voltage reference circuit with high stability and accuracy is critical for the performance of the fluorescent optical fiber temperature sensor system. It directly impacts the signal quality of the fluorescence detection circuit and the accuracy of the analog-to-digital converter sampling. Bandgap references (BGR) are widely used in SoC for their stability. To ensure the accuracy of fluorescent optical fiber temperature sensors, it is crucial to implement a BGR with a low temperature coefficient [1-4]. This paper proposes a bandgap reference circuit with high-order curvature compensation (HCC_BGR) based on a standard 0.18μm CMOS process. Measurement results show that the proposed HCC_BGR circuit generates a stable 1.22V reference voltage with a low temperature coefficient (TC) of 5.56 ppm/°C in the temperature range of -20°C to 85°C. Compared to a traditional BGR (TRA_BGR) circuit, the HCC_BGR reduces temperature coefficient by 3.07 times. Moreover, the low dropout linear regulator (LDO) using the proposed HCC_BGR exhibits a low line sensitivity of 1.52%/V from 3.4V to 5V.