Title :
Sensor impedance spectrum measurement interface with lock-in amplifier
Author :
Ma, ShengQian ; Schröder, Jens ; Hauptmann, Peter
Author_Institution :
Inst. for Electr. & Inf. Technol., Northwest Normal Univ., China
Abstract :
For impedance spectrum measurement of semiconducting oxide gas sensors a wide frequency range and a low AC voltage are required which leads to a lower signal-to-noise ratio. A sensor interface based on an Anderson loop and a lock-in amplifier technique is presented, covering a frequency range from DC to 100 kHz. The calculation of the sensor impedance from measured voltages and the calibration of the interface to overcome unwanted phase shifts and nonlinear effects in the circuit components are described. Simulation and experimental results are given.
Keywords :
calibration; electric sensing devices; frequency response; gas sensors; instrumentation amplifiers; spectral analysers; 0 to 100 kHz; AC voltage; Anderson loop; calibration; frequency range; impedance spectrum measurement interface; lock-in amplifier; nonlinear effects; semiconducting oxide gas sensors; signal-to-noise ratio; unwanted phase shifts; Amplifiers; Frequency measurement; Gas detectors; Impedance measurement; Lead compounds; Low voltage; Phase measurement; Semiconductivity; Sensor phenomena and characterization; Signal to noise ratio;
Conference_Titel :
Sensors, 2002. Proceedings of IEEE
Print_ISBN :
0-7803-7454-1
DOI :
10.1109/ICSENS.2002.1037308
