Signal conditioning piezoelectric sensors (AAJ) （信号调节压电传感器(AAJ)）.pdfVIP

Amplifiers: Op Amps Texas Instruments Incorporated Signal conditioning for piezoelectric sensors By Eduardo Bartolome Systems Engineer, Medical Business Unit Introduction Figure 1. Sensor under This article explains some of the principles of signal condi- acceleration tioning. Piezoelectric sensors have been chosen to illus- trate these principles because their conditioning requires a mix of traditional tools and because they present some challenges that may not arise with other types of sensors. Piezoelectric sensors The application of piezoelectric transducers for sensing Fint and actuation extends to many fields. This article focuses on the sensing of a group of physical magnitudes—acceler- ation, vibration, shock, and pressure—that from the per- spective of the sensor and its requied signal conditioning can be considered similar.1 In the case of acceleration, Fext sensor sensitivity is usually expressed as a charge propor- tional to an external force or acceleration (many times described as gravitational acceleration, g). Nevertheless, in the strict physical sense, the sensor outputs a charge oscillatory force will produce relatively large displacements that is actually a function of its deformation/deflection. and therefore large output amplitudes. For instance, Figure 1 shows a sensor fixed on the top If the effects of the resonance are ignored, piezoelectric while the bottom is bei