A compact temperature switch for automotive applications

Master thesis (2022)

Authors

A.M. Buduguppa Electrical Engineering, Mathematics and Computer Science

Contributors

K.A.A. Makinwa Microelectronics (mentor)
Faculty
Electrical Engineering, Mathematics and Computer Science, Electrical Engineering, Mathematics and Computer Science
Copyright: © 2022 Aravind Buduguppa
More Info
expand_more

Published Date

28-01-2022

Language

English

Reuse Rights

Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.

Faculty

Electrical Engineering, Mathematics and Computer Science

Abstract

To prevent microprocessors from getting too hot or too cold, multiple temperature sensors are required to monitor their internal temperatures at different locations. Such sensors should be as compact as possible
to maximize their usage in dense layouts and should be able to cover a wide temperature range. This thesis describes a compact temperature threshold sensor which consists of a BJT-based sensor core, a programmable DAC to set thresholds, and a single amplifier. The sensor operates in two steps, namely the ‘bias mode’ and the ‘comparison mode’. In ‘bias mode’, the amplifier is configured to bias the sensor core, and in ‘comparison mode’, the amplifier is configured to compare a CTAT and a PTAT voltage and output a 1-bit digital signal. The threshold setting is programmable via the DAC, which facilitates the
detection over the automotive temperature range (-40⁰C to 150⁰C). Fabricated in 0.16µm CMOS process, the sensor achieves a threshold detection accuracy of ±2.10⁰C (3σ) after a one-point digital trim at room temperature. The sensor occupies an area of 0.05mm2 and has a current consumption of 15.5µA at 27⁰C.