Title :
A piezoresistive pressure sensor interfacing circuit
Author :
Vlassis, S. ; Siskos, S. ; Laopoulos, Th
Author_Institution :
Dept. of Phys., Aristotelian Univ. of Thessaloniki, Greece
Abstract :
A signal conditioning circuit with digital output for piezoresistive pressure sensors based on CMOS current mode building blocks is presented. The proposed circuit uses an instrumentation amplifier (IA) based on operational floating amplifiers (OFA), adapted for resistive sensors. This IA offers a output current which is independent of tracking and offset errors. Two piezoresistors with current supply are used against four piezoresistors of the basic Wheatstone bridge. A new temperature compensation technique for the pressure sensitivity is described. Also an accurate SPICE model for piezoresistive sensors is introduced. Simulation as well as experimental results are included to demonstrate the performance of the circuit
Keywords :
CMOS analogue integrated circuits; SPICE; bridge circuits; current conveyors; current-mode circuits; digital readout; equivalent circuits; error compensation; feedback amplifiers; instrumentation amplifiers; operational amplifiers; piezoresistive devices; pressure sensors; sigma-delta modulation; signal processing equipment; thin film resistors; CMOS current mode building blocks; Wheatstone bridge; accurate SPICE model; circuit performance; current conveyor; digital output; equivalent circuit; error compensation; feedback configuration; instrumentation amplifier; interfacing circuit; operational floating amplifiers; piezoresistive pressure sensors; piezoresistors; pressure sensitivity; sigma-delta convertor; signal conditioning circuit; simulation; temperature compensation technique; thin film sensing resistor; Bridge circuits; CMOS digital integrated circuits; Circuit simulation; Current supplies; Instruments; Operational amplifiers; Piezoresistance; Piezoresistive devices; SPICE; Temperature sensors;
Conference_Titel :
Instrumentation and Measurement Technology Conference, 1999. IMTC/99. Proceedings of the 16th IEEE
Conference_Location :
Venice
Print_ISBN :
0-7803-5276-9
DOI :
10.1109/IMTC.1999.776766
