JSSC 2020第2期Data Converters0.16μm CMOS

A BJT-Based Temperature-to-Digital Converter With a ±0.25◦C3 σ-Inaccuracy From − 40◦Ct o +180◦C Using Heater-Assisted V oltage Calibration

一种基于BJT的温度数字转换器，通过加热辅助电压校准实现高精度。

±0.25°C 3σ精度，-40°C至+180°C范围，0.15mm²面积，1.8V供电

温度传感器BJT数字转换器开关电容ADC片上加热器

▸采用双采样电容的开关电容ADC，减少关键采样开关数量

▸集成片上加热器，快速升温至110°C

▸无需温控环境即可完成两点电压校准

Abstract

This article presents a BJT-based temperature-to- digital-converter (TDC) that achieves ±0.25 ◦C3 σ-inaccuracy from −40 ◦Ct o +180 ◦C after a heater-assisted voltage calibra- tion (HA-VCAL). Its switched-capacitor (SC) ADC employs two sampling capacitors and, thus, the minimum number of critical sampling switches, which minimizes the effects of switch leakage at high temperatures and improves accuracy. The TDC is also equipped with an on-chip heater, with which the sensing BJTs can be rapidly ( <0.5 s) heated to about 110 ◦C. This, in turn, enables VCAL at two different temperatures without the need for a temperature-controlled environment. Realized in a 0.16- μm standard CMOS, the TDC, including the on-chip heater, occupies 0.15 mm 2 and operates from 1.8 V .