Application Note

Designing Operational Amplifier Oscillator Circuits For Sensor Applications

Source: Microchip Technology Inc.

Operational amplifier (op amp) oscillators can be used to accurately measure resistive and capacitive sensors. Oscillator design can be simplified by using the procedure discussed in this application note. The derivation of the design equations provides a method to select the passive components and determine the influence of each component on the frequency of oscillation. The procedure will be demonstrated by analyzing two state-variable RC op-amp oscillator circuits.