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1. The problem statement, all variables and given/known data:
Find the time constant of an inverting op amp with C = 50uF, Ri = 200 Ohms, Rf = 20 Ohms.
This is a problem I have found in a prep book for the Fundamentals of Engineering Exam (Electrical component). The book gives the answer as time constant = Rf * C. I am not exactly sure what kind of op amp you would classify this as. My first thought is that it is a practical differentiator. But you got that resistor and capacitor on the input side. Surely, Ri on the input side should have some say in the time constant. I tried to go about this question by considering that the current on the input side is equal to the current on the output side. My goal was to try to prove the book's answer by finding a gain equation in terms of just Rf and C but have been unsuccessful. Looking to see if I can get some help on this. I just might be approaching this differently. These questions are supposed to be simple.
Thanks! Dan.
2. Relevant equations
3. The attempt at a solution
Find the time constant of an inverting op amp with C = 50uF, Ri = 200 Ohms, Rf = 20 Ohms.
This is a problem I have found in a prep book for the Fundamentals of Engineering Exam (Electrical component). The book gives the answer as time constant = Rf * C. I am not exactly sure what kind of op amp you would classify this as. My first thought is that it is a practical differentiator. But you got that resistor and capacitor on the input side. Surely, Ri on the input side should have some say in the time constant. I tried to go about this question by considering that the current on the input side is equal to the current on the output side. My goal was to try to prove the book's answer by finding a gain equation in terms of just Rf and C but have been unsuccessful. Looking to see if I can get some help on this. I just might be approaching this differently. These questions are supposed to be simple.
Thanks! Dan.
2. Relevant equations
3. The attempt at a solution
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