integrator op amp

The purpose of this lab was to learn how to use an oscilloscope to measure time varying signals. For this lab we used a function generator to produce the signals. We used the function generator to create both periodic sine waves, and square waves to display on the oscilloscope. We then used the divisions on the screen, and the increments per division to calculate the amplitudes, frequencies, and voltages when crossed with a battery. To verify our scope calculations, we measured the output of the function generator with a DMM. Then we used what we learned to calculate two mystery signals.The Syscomp CircuitGear was used to generate the waves and record their integrals as shown in sample shots below.

 The figures below shows the input signals (red) and their integrals (blue):

Using the function generator, we can add an offset to the function, which will be displayed by the oscilloscope. By observing the difference, we can come to understand how step functions apply.

Question Answer:

If there was a DC component in the input waveform and the 10M ohm resistor wasn't present, then charges will eventually build up on the capacitor, and the entire feedback loop would become an open circuit. The 10M ohm resistor prevents this from happening. Integrating a constant would continue increasing the output voltage until the circuit reaches saturation.