A 2.5 V, 2.56 ppm/°C Curvature-Compensated Bandgap Reference for High-Precision Monitoring Applications

• Published in: Micromachines (Basel) Vol. 13; no. 3; p. 465
• Main Authors: Zhu, Guangqian, Fu, Zhaoshu, Liu, Tingting, Zhang, Qidong, Yang, Yintang
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 18.03.2022; MDPI
• Subjects: Accuracy; bandgap reference; battery monitoring; BCD process; Bipolar transistors; Circuits; Curvature; curvature compensation; Design; Electric potential; Energy gap; low temperature coefficient; Monitoring; Temperature; Temperature effects; Transistors; Voltage; curvature compensation; bandgap reference; BCD process; battery monitoring; low temperature coefficient
• ISSN: 2072-666X; 2072-666X
• DOI: 10.3390/mi13030465

This work presents a high-precision high-order curvature-compensated bandgap voltage reference (BGR) for battery monitoring applications. The collector currents of bipolar junction transistor (BJT) pairs with different ratios and temperature characteristics can cause greater nonlinearities in ΔV . The proposed circuit additionally introduces high-order curvature compensation in the generation of ΔV , such that it presents high-order temperature effects complementary to V . Fabricated using a 0.18 µm BCD process, the proposed BGR generates a 2.5 V reference voltage with a minimum temperature coefficient of 2.65 ppm/°C in the range of -40 to 125 °C. The minimum line sensitivity is 0.023%/V when supply voltage varies from 4.5 to 5.5 V. The BGR circuit area is 382 × 270 μm , and the BMIC area is 2.8 × 2.8 mm .