How to Measure Op-Amp Input Capacitance to Minimize Noise (Download)
While measuring op-amp input capacitance, what should you focus on? The answer is that you must ensure the measurement accuracy isn’t degraded by the stray capacitance and inductance of the PCB or test setup. You can minimize these issues by using probes with low capacitance, using short lines on the PCB, and avoiding huge ground planes below the signal traces.
Operational amplifiers are employed in a wide variety of electronic circuits. Their task is to amplify small electrical voltages for further signal processing. Applications such as smoke detectors, photodiode transimpedance amplifiers, medical instruments, and even industrial control systems require the lowest possible op-amp input capacitance. That’s because, among other things, it affects the noise component, which in turn affects system stability, especially for systems with high frequencies and gains.