Title :
A fully-differential chopper-stabilized Sigma-delta interface for micro-accelerometer
Author_Institution :
Beijing Microelectron. Technol. Inst. (BMTI), Beijing, China
Abstract :
This paper presents a fully-differential Sigma-delta (ΣΔ) CMOS interface with chopper-stabilization (CHS) for an acceleration sensing system. The Capacitive sensor interface consists of a front-end capacitance to voltage converter (CVC) and a back-end second-order switched-capacitor (SC) ΣΔ modulator. Correlated-Double-Sampling (CDS) techniques and CHS were used in the charge amplifier to remove the parasitic capacitance of MEMS sensor and the noise from the readout electronic circuit. This architecture decouples the MEMS sensor from the optimized-performance ΣΔ modulator. The top-down methodology has been followed for the design of the interface. This work is designed and implemented in a 0.35um CMOS technology with 3.3V supply voltage. Simulation results show sensitivity of 0.55V/g is achieved in the range of ±1g with a 5.12MHz sampling frequency.
Keywords :
CMOS integrated circuits; accelerometers; choppers (circuits); convertors; correlation methods; sigma-delta modulation; CMOS interface; acceleration sensing system; capacitance to voltage converter; chopper-stabilization; correlated-double-sampling; frequency 5.12 MHz; fully-differential chopper-stabilized sigma-delta interface; micro-accelerometer; size 0.35 mum; voltage 3.3 V; Accelerometers; CMOS integrated circuits; Frequency conversion; Frequency modulation; Monitoring; Σ Δ; CHS; MEMS; SC; accelerometer;
Conference_Titel :
Mechanical and Electrical Technology (ICMET), 2010 2nd International Conference on
Conference_Location :
Singapore
Print_ISBN :
978-1-4244-8100-2
Electronic_ISBN :
978-1-4244-8102-6
DOI :
10.1109/ICMET.2010.5598457
