Question

35 point problem 7. An OpAmp has the following open loop gain: AS) where - 4 Hz, and A, -10 5 points a.) What is the absolute low frequency open-loop gain of the OpAmp? 5 points b.) What is the low frequency open-loop gain of the OpAmp in dB? 5 points c.) What is the -3dB frequency of the open-loop Op Amp? 5 points d.) What is the gain-bandwidth product of this OpAmp? 5 points e.) What is the maximum useful frequency of the OpAmp? 10 points 1.) Sketch below a Bode Plot of the gain magnitude vs. frequency for the OpAmp. Label your horizontal and vertical axis carefully and completely. You must indicate items a.) through e.) above on your Bode Plot.

Answer 1

Ans. 7 Ао ginen Alfi - T + j (+ / S The magnitude is Alf) 1 = om where to = 105 fed = 4H3 (a) for low frequency absolute gain is IA (o)l so (1 Aco)! = Ao = 105) gain in dB = 20 log do = 20 log 105= loodB (6) les at -3dB 1441 = to so Vi+17-3dB) 2 7-3d 2= 1+ (1-3 dB) 2

1-3 dB = fed = 4H3) (d) GB Wp = GB WP = Ao Ao far - 10x 4 = 4X10S H₃ / (es as gain decrease above the useful frequency in -3dB fregrency so it open - (f) IA(fil Ao 7 los - (loodB) Тен - + завечн GBWP = UXIOSH3