A CMOS Resistor-Based Temperature Sensor with a 10fJ∙K2 Resolution FoM and 0.4°C (3σ) Inaccuracy From −55°C to 125°C After a 1-point Trim

📋 论文概要

提出了一种基于电阻的CMOS温度传感器，采用惠斯通电桥和连续时间ΔΣ调制器读出，通过嵌入return-to-CM DAC和尾电阻线性化OTA，实现了10fJ∙K2的能效指标和0.4°C（3σ）的高精度，覆盖-55°C到125°C的宽温度范围。

💡 主要创新点

• 采用return-to-CM (RCM) DAC技术，提升了连续时间ΔΣ调制器的能效，从而降低整体功耗。
• OTA中使用尾电阻线性化方案，改善了调制器的线性度和噪声性能，有助于提高温度传感精度。
• 将DAC嵌入调制器结构中，进一步优化了系统集成度和能量效率。

🏷 关键词

📄 原文摘要

Energy efficiency and accuracy are important specifications of CMOS temperature sensors. BJT-based sensors achieve state-of-the-art accuracy [1], while Wheatstone-bridge (WhB) sensors achieve lower accuracy but state-of-the-art energy efficiency [2,3]. This paper presents a WhB sensor that is read out by an energy-efficient continuous-time delta-sigma modulator (CTDSM). Compared to [2,3], the modulator achieves better energy efficiency with the help of a returnto-CM (RCM) DAC and an OTA with a tail-resistor linearization scheme. Moreover, better accuracy is achieved by embedding the DAC in the bridge and by using more sensitive silicided-diffusion resistors instead of silicided-poly resistors. Compared to the state-of-the-art [3], the proposed sensor achieves a 2" improvement in resolution FoM (10fJ∙K2), and a 2" improvement in inaccuracy (0.4°C (3σ) from -55°C to 125°C after a 1-point trim).

👥 作者与机构

Sining Pan, Kofi A. A. Makinwa

Delft University of Technology, Delft, The Netherlands