A 2µA temperature compensated mems-based real time clock with ±4 ppm timekeeping accuracy

Author

Gronicz, Jakub ; Pulkkinen, Mika ; YuÌˆcetasÌ§, Mikail ; Halonen, Kari

Author_Institution

Dept. of Micro & Nanosci., Aalto Univ., Espoo, Finland

fYear

2014

fDate

1-5 June 2014

Firstpage

514

Lastpage

517

Abstract

This paper presents a MEMS-based real time clock with a temperature compensation system. The implemented circuit achieves a timekeeping accuracy of ±4 ppm over -40 °C... 85 °C temperature range. It is built using a 27 kHz silicon resonator, differential PTAT temperature sensor with a 2^nd order ΣΔADC, and a DSP block for temperature frequency compensation. The circuit is powered by a 1.8V supply and draws 2 μA current. The system has been implemented using a 0.18 μm CMOS process.

Keywords

CMOS digital integrated circuits; clocks; compensation; digital signal processing chips; low-power electronics; resonators; sigma-delta modulation; temperature sensors; 2nd order ΣΔADC; CMOS process; DSP block; MEMS-based real time clock; current 2 muA; differential PTAT temperature sensor; frequency 27 kHz; silicon resonator; size 0.18 mum; temperature -40 C to 85 C; temperature compensation system; temperature frequency compensation; Clocks; Frequency measurement; Oscillators; Resonant frequency; Silicon; Temperature measurement; Temperature sensors;

fLanguage

English

Publisher

ieee

Conference_Titel

Circuits and Systems (ISCAS), 2014 IEEE International Symposium on

Conference_Location

Melbourne VIC

Print_ISBN

978-1-4799-3431-7

Type

conf

DOI

10.1109/ISCAS.2014.6865185

Filename

6865185