Fundamentals-of-Microelectronics-Behzad-Razavi.pdf

Using the op amp model depicted in fig 844 compute in

Info icon This preview shows pages 438–441. Sign up to view the full content.

View Full Document Right Arrow Icon
Using the op amp model depicted in Fig. 8.44, compute in terms of and . 34. Consider the voltage adder illustrated in Fig. 8.56, where is a parasitic resistance and the R R X 2 out V F R 1 V 1 V 2 A 0 R P Figure 8.56 op amp exhibits a finite input impedance. With the aid of the op amp model shown in Fig. 8.43, determine in terms of and . 35. Plot the current flowing through in the precision rectifier of Fig. 8.22(b) as a function of time for a sinusoidal input. 36. Plot the current flowing through in the precision rectifier of Fig. 8.23(a) as a function of time for a sinusoidal input. 37. Figure 8.57 shows a precision rectifier producing negative cycles. Plot , , and the R 1 X Y V out in V D 1 Figure 8.57 current flowing through as a function of time for a sinusoidal input. 38. Consider the precision rectifier depicted in Fig. 8.58, where a parasitic resistor has ap- peared in parallel with . Plot and as a function of time in response to a sinusoidal input. Use a constant-voltage model for the diode. 39. We wish to improve the speed of the rectifier shown in Fig. 8.22(b) by connecting a diode from node to ground. Explain how this can be accomplished. 40. Suppose in Fig. 8.24 varies from V to V. Sketch and as a function of if the op amp is ideal.
Image of page 438

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
BR Wiley/Razavi/ Fundamentals of Microelectronics [Razavi.cls v. 2006] June 30, 2007 at 13:42 414 (1) 414 Chap. 8 Operational Amplifier As A Black Box R 1 X Y V out in V D 1 R P Figure 8.58 41. Suppose the gain of the op amp in Fig. 8.24 is finite. Determine the input/output character- istic of the circuit. 42. A student attempts to construct a noninverting logarithmic amplifier as illustrated in Fig. 8.59. Describe the operation of this circuit. R X in V 1 out V Q 1 Figure 8.59 43. Determine the small-signal voltage gain of the logarithmic amplifier depicted in Fig. 8.24 by differentiating both sides of (8.66) with respect to . Plot the magnitude of the gain as a function of and explain why the circuit is said to provide a “compressive” characteristic. 44. The logarithmic amplifier of Fig. 8.24 must “map” an input range of 1 V to 10 V to an output range of V to V. (a) Determine the required values of and . (b) Calculate the small-signal voltage gain at the two ends of the range. 45. The circuit illustrated in Fig. 8.60 can be considered a “true” square-root amplifier. Deter- R X in V 1 out V M 1 V TH Figure 8.60 mine in terms of and compute the small-signal gain by differentiating the result with respect to . 46. Calculate in terms of for the circuit shown in Fig. 8.61. 47. In the noninverting amplifier of Fig. 8.62, the op amp offset is represented by a voltage source in series with the inverting input. Calculate . 48. Suppose each op amp in Fig. 8.28 suffers from an input offset of 3 mV. Determine the maximum offset error in if each amplifier is designed for a gain of 10.
Image of page 439
BR Wiley/Razavi/ Fundamentals of Microelectronics [Razavi.cls v. 2006] June 30, 2007 at 13:42 415 (1) Sec. 8.6 Chapter Summary 415 R X in V 1 out V M 1 Figure 8.61 V in A 0 out V R 1 R 2 V OS Figure 8.62 49. For the inverting amplifier illustrated in Fig. 8.63, calculate if the op amp exhibits an A 0 R 1 R 2 in V out V Figure 8.63 input offset of . Assume .
Image of page 440

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 441
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern