Egr 2105 - Signal Amplification ,Op Amp


© N. B. Dodge 01/12

Op Amp Worksheet

1. Operational amplifiers have several basic characteristics, including high input impedance (~ 1 Mega Ω), low output impedance (typically < 500 Ω),

and a specific gain range. What is a typical gain of an op amp in common devices (you

may need to do some research)?

2. The gain of an amplifier is a measure of its ability to add power to a signal. Based on information in the Lecture and/or Theory portion of lab, write down a simple

gain formula in terms of input signal and output voltage:

3. The formula you develop above gives the gain of the negative feedback amplifier,

allowing you to set the amount of gain that it will provide. Suppose you have two

inverting amplifiers with gains of 𝐾1 = −10 and 𝐾2 = −20, and you connect the output of the first to the input of the second. What is the overall gain of this

“cascaded” set of two amplifiers? Is the result positive or negative? Is the output

from the second output in phase or out of phase with the original signal?