Wednesday, April 26, 2017

Summing Amplifier

Summing Amplifier

In this lab, we calculate the three resistors and set up a Summing Amplifier Circuit in order to record the amount of Vout. This output voltage will be measured by adjusting Va. 

From the picture below, we calculated that the three resistors will have the same resistance of 2.2KΩ. 



Then after measuring the three resistors, we got the actual amount of resistance and then we set up the circuit as shown below: 


Once the circuit is set up, we then adjust the Va voltage to find the output voltage. As shown below, Vb is a constant 1: 











Inverting Voltage Amplifier

Inverting Voltage Amplifier

In this lab, we designed an inverting Voltage Amplifier circuit using two resistors and an OP 27. This circuit is designed to provide a gain of 2.2 with an input resistor of approximately 2.2 KΩ. To obtain the resistance of R2, it is calculated using the equation:
Gain = R2/R1. Then, we get that the resistance of R2 should be 4.7KΩ. 


In this picture, the actual schematic of the circuit is shown with the actual measurements of the resistance. 


Once the circuit has been set up, we measure the gain from the amplifier of the OP27 and saw that it has close to the gain of 2.2. Then, we measure the amount of output voltage given depending on how much input voltage we put in as shown on the picture below: 









From the fact that our actual gain is very close to the expected gain, there might only be a very small amount of saturation. 



During lecture, we learned about how to calculate gain from the circuit. Then, we also discussed about how to draw the output voltage graph as shown below: 










Summary
For this lecture, we learned about calculating gain and making the output voltage graph. In lab, we design an inverting voltage amplifier and calculate the resistance needed to obtain a gain of 2.2. What we got from making the circuit was a gain of 2.19 after calculating the resistance of the second resistor.