-55 degrees C to 170 degrees C High Linear Voltage References Circuitry in 0.18\`im Cmos Technology

TL;DR

This paper presents a high linearity voltage reference circuit in 0.18μm CMOS technology that maintains stability and accuracy over a wide temperature range from -55°C to 170°C, suitable for system-on-chip integration.

Contribution

It introduces a temperature complementation technique combining PTAT and IOAT references to improve linearity and stability across a broad temperature spectrum.

Findings

Linearity with R-squared > 0.999 over -55°C to 170°C

Enhanced stability of IOAT voltage reference

Suitable for integrated temperature sensors in SoC designs

Abstract

High linear voltage references circuitry are designed and implemented in TSMC 0.18$\mu$m CMOS technology. Previous research has proposed the use of MOS transistors operating in the weak inversion region to replace the bipolar devices in conventional PTAT(proportional to absolute temperature) circuits. However such solutions often have linearity problem in high temperature region due to the current leaking devices in modern deep sub micron and nano-scale CMOS technology. The proposed circuit utilized temperature complementation technique on two voltage references, PTAT and IOAT (independent of absolute temperature) references, to enhance the linearity and produce a more stable IOAT voltage reference. Base on the simulation results, the R-squares of both circuitries are better than 0.999 in a considerable wider temperature range from -55 degrees C to 170 degrees C. Thus, a fully integrated temperature sensor with wider temperature range is designed and easily to integrate to modern system-on-chip designs with minimal efforts.