But even better, try to figure it out on your own first! As I know that 90% of you will look this up on the internet, you must cite any sources you use, and you must show, using the golden rules and basic circuit analysis, why your circuits are correct. Using an ideal op amp, a resistor, and a capacitor, design (a) a circuit wherein the output voltage is the integral of the input signal, and (b) a circuit wherein the output voltage is the derivative of the input signal (edit on Sep 21: do not worry if the result is inverted, as I know you know how to add a simple inverting stage after the result). If you absolutely cannot resist the temptation, you must cite any sources that you use.ĥ Can an op amp do your calculus homework? Can you design a circuit to use a single op amp and a unipolar supply to add two signals together without inverting the result? Please try to do this without looking it up on the internet, in a book, etc. While you could add a second inverting op-amp stage to bring this back into the positive domain, there are times when this is not possible (for instance, when you have a unipolar supply).

In problem 1 you analyzed a circuit that was designed to add multiple analog signals together, but you may have noticed that it also inverts the signal (or, if you didn't, now you will). Show a schematic and write the expression relating photo-transistor current to output voltage. You have a unipolar +5V supply, but you may assume ideal op-amps. Design a trans-resistive amplifier for a photo-transistor such that the circuit will have an output of 2.5V with no light falling on the sensor and an output voltage that rises with increasing light levels.

Op amp phototransistor circuit