11 - Op-Amps

INTRO: The Operational Amplifier is an electronic device that we will be covering today. This device, commonly called an Op-Amp, is capable of amplifying the input voltage. It also has the ability to reverse the polarity of the input voltage and performing mathematical operations. It is this last property that puts the "operational" in the name. The ability of the op-amp to perform many functions comes from the complex inner-workings, as well as the multiple inputs available.


 
We began class by writing down the 5 circuit elements that we have covered thus far. It was a good review to be able to consolidate everything we have worked with down to 5 categories. 

 
This above picture demonstrates the input availability on the bottom diagram. As mentioned above, this is key in allowing the op-amp to perform many functions
  
LAB: Inverting Voltage Amplifier
In this lab we will explore a type of op-amp. The inverting type reverses the polarity of the input voltage, as well as amplifying it. 


Above is our pre-lab where we found a relationship between Vin and Vout. After some work we arrived at Vout equaling -2Vin, which makes practical sense given the ability of the inverting op-amp.

 
Above is a picture of our circuit set up as the diagram requested. A key property of inverting amps is that the output voltage goes back to the inverting input, after going through a resistor of course.

 
 Above is the graph of Vin vs. Vout. As we predicted earlier in the pre-lab, they do have a 2-1 relationship. It is also important to note that just like a transistor, the op-amp experiences saturation, which can be seen in the above diagram.