Title :
118-dB dynamic range, continuous-time, opened-loop capactance to voltage converter readout for capacitive MEMS accelerometer
Author :
Kevin, T.C.C. ; Han, Dong ; Ravinder, P.S. ; Duy, D.P. ; Chin, Y.P. ; Jian, W.L. ; Nuttman, David ; Je, Minkyu
Author_Institution :
Inst. of Microelectron., A*STAR (Agency for Sci., Technol. & Res.), Singapore, Singapore
Abstract :
A high performance analog front-end (AFE) interface circuit for capacitive MEMS accelerometer is presented in this paper. The AFE was implemented in a continuous-time (CT), chopper stabilized, capacitance to voltage converter (CVC) topology with a variable gain amplifier (VGA) for greater flexibility and a low pass filter (LPF) which limited the signal bandwidth to 300 Hz. Noise analysis of each building block of the AFE is also presented in this paper. The measured input referred noise density is 27 nV/√Hz. Long term stability results showed that the input offset has an Allan deviation floor of 60 nVrms. The nonlinearity for the AFE was measured at ± 1 %.
Keywords :
accelerometers; amplifiers; capacitive sensors; convertors; detector circuits; low-pass filters; microsensors; readout electronics; analog front-end interface circuit; bandwidth 300 Hz; capacitive MEMS accelerometer; chopper stabilized circuit; continuous time capacitive accelerometer; dynamic range capacitive accelerometer; low pass filter; noise analysis; open loop capactance-to-voltage converter readout; variable gain amplifier; Accelerometers; Capacitive sensors; Choppers; Micromechanical devices; Noise; Resistors;
Conference_Titel :
Solid State Circuits Conference (A-SSCC), 2010 IEEE Asian
Conference_Location :
Beijing
Print_ISBN :
978-1-4244-8300-6
DOI :
10.1109/ASSCC.2010.5716626
