Title :
A micropower battery current sensor with ±0.03% (3σ) inaccuracy from −40 to +85°C
Author :
Shalmany, S.H. ; Draxelmayr, D. ; Makinwa, Kofi A. A.
Author_Institution :
Delft Univ. of Technol., Delft, Netherlands
Abstract :
This paper presents a micropower current-sensing system (CSS) for battery monitoring, which consists of a calibrated shunt resistor, a ΔΣ ADC, and a dynamic bandgap reference (BGR). For currents ranging from 0 to 1A over the industrial temperature range (-40°C to +85°C), it exhibits 10μA offset and ±0.03% (3σ) gain error, which is a 3× improvement on systems with off-chip external references [1,2]. This level of accuracy is achieved by the use of dynamic error-correction techniques, digital temperature compensation, and an on-chip dynamic BGR, whose spread is corrected by a single room-temperature trim.
Keywords :
analogue-digital conversion; calibration; compensation; delta-sigma modulation; electric current; electric sensing devices; energy gap; error correction; resistors; ΔΣ ADC; CSS; battery monitoring; calibrated shunt resistor; current 0 A to 1 A; current 10 muA; digital temperature compensation; dynamic bandgap reference; dynamic error-correction technique; industrial temperature; micropower battery current sensor; micropower current-sensing system; off-chip external reference; on-chip dynamic BGR; temperature -40 C to 85 C; temperature 293 K to 298 K; Batteries; Cascading style sheets; Measurement uncertainty; Polynomials; Resistors; Temperature measurement; Temperature sensors;
Conference_Titel :
Solid-State Circuits Conference Digest of Technical Papers (ISSCC), 2013 IEEE International
Conference_Location :
San Francisco, CA
Print_ISBN :
978-1-4673-4515-6
DOI :
10.1109/ISSCC.2013.6487781
