Cascading Op-Amp Lab
In this lab we used a dual input/output op-amp to design a circuit that would sum and invert two input voltages and then perform a second sum and inversion to yield a final result. As seen below, the first op-amp would yield the inverse of the sum of half of V1 and half of V2. With inputs of 1 and 2 volts this would yield -1.5V. The second op amp uses a voltage divider for the non-inverting input to ensure the circuit is below saturation voltage. The output of the first op-amp is connected to the inverting input of the second op-amp to invert the voltage from the first stage and yield a positive output voltage from the second op-amp.
As seen above, the output voltage was different from our anticipated voltage but the sign of the voltage was as expected. The output of the first stage was much closer to the anticipated value from the calculations. When we plugged in the output from the first stage into the calculation with the actual resistances of the resistors used our value agreed with the actual value obtained.
Comments
Post a Comment