This paper presents a fully integrated ±4A current sensor that supports a 25V input common-mode voltage range (CMVR) while operating from a single 1.5V supply. It consists of an on-chip metal shunt, a beyond-the-rails ADC [1] and a temperature-dependent voltage reference. The beyond-the-rails ADC facilitates high-side current sensing without the need for external resistive dividers or level shifters, thus reducing power consumption and system complexity. To compensate for the shunt's temperature dependence, the ADC employs a proportional-to-absolute-temperature (PTAT) reference voltage. Compared to digital temperature compensation schemes [2,3], this analog scheme eliminates the need for a temperature sensor, a band-gap voltage reference and calibration logic. As a result, the current sensor draws only 10.9μA and is 10x more energy efficient than [2]. Over a ±4A range, and after a one-point trim, the sensor exhibits a 0.9% (max) gain error from -40°C to 85°C and a 0.05% gain error at room temperature. The former is comparable with that of other fully-integrated current sensors [2-4], while the latter represents the state-of-the-art.

Original languageEnglish
Title of host publication2018 IEEE International Solid-State Circuits Conference, ISSCC 2018
Subtitle of host publicationDigest of Technical Papers
EditorsL.C. Fujino
Place of PublicationLewiston, USA
PublisherIEEE
Pages324-326
Number of pages3
Volume61
ISBN (Electronic)978-1-5090-4940-0
ISBN (Print)978-1-5386-2227-8
DOIs
Publication statusPublished - 2018
Event65th IEEE International Solid-State Circuits Conference, ISSCC 2018 - San Francisco, United States
Duration: 11 Feb 201815 Feb 2018

Conference

Conference65th IEEE International Solid-State Circuits Conference, ISSCC 2018
CountryUnited States
CitySan Francisco
Period11/02/1815/02/18

    Research areas

  • Temperature sensors, Temperature distribution, Capacitors , Temperature dependence, Temperature measurement, Metals

ID: 46986678