25If this is not apparent, imagine a scenario where the +1.7 volt input existed for precisely one second’s worth of time. However much the output voltage ramps in that amount of time must therefore be its rate of change in volts per second (assuming a linear ramp). Since we know the area accumulated under a constant value of 1.7 (high) over a time of 1 second (wide) must be 1.7 volt-seconds, and τi is equal to 3.807 seconds, the integrator circuit’s output voltage must ramp 0.447 volts during that interval of time. If the input voltage is positive and we know this is an inverting opamp circuit, the direction of the output voltage’s ramping must be negative, thus a ramping rate of −0.447 volts per second.