A High-Precision Current-Mode Bandgap Reference With Low-Frequency Noise/Offset Elimination

Abstract

This brief presents a low-noise, low-offset bandgap reference for the biomedical electronic systems application. In order to reduce the low-frequency noise and increase the accuracy, the low-frequency noise/offset elimination technique based on current-mode bandgap reference (BGR) is proposed. Besides, this BGR utilizes a proportional to absolute temperature (PTAT) resistor feedback technique to minimize the low-frequency noise and offset from the current mirrors. The proposed BGR is implemented in a 180 nm deep n-well CMOS process occupying an active area of 0.0725 mm 2. The measured results indicate that the BGR outputs 0.6 V voltage and consumes <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$69~\mu \text{A}$ </tex-math></inline-formula> current under 1.2 V supply voltage. It can achieve <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$3.5~\mu \text{V}$ </tex-math></inline-formula> (rms) noise from 0.1 to 10 Hz and a 0.21% DC accuracy.