11.25For the amplifier described in Exercise 11.24, rather than introducing a new dominant pole, we can use additional capacitance at the circuit node at which the first pole is formed to reduce the frequency of the first pole. If the ...

11.24A multipole amplifier having a first pole at 1 MHz and a dc open-loop gain of 100 dB is to be compensated for closed-loop gains as low as 20 dB by the introduction of a new dominant pole. At what ...

11.23For the amplifier whose open-loop-gain frequency response is shown in Fig. 11.38, find the value of β that results in a phase margin of 45°. What is the corresponding closed-loop gain? 10−4; 80 dB

11.22Find the closed-loop gain at ω1 relative to the low-frequency gain when the phase margin is 30°, 60°, and 90°. 1.93; 1; 0.707

11.21Consider an op amp having a single-pole, open-loop response with A0 = 105 and fP = 10 Hz. Let the op amp be ideal otherwise (infinite input impedance, zero output impedance, etc.). If this amplifier is connected in the noninverting ...

11.20Consider a feedback amplifier for which the open-loop transfer function A(s) is given by

11.19An amplifier with a low-frequency gain of 100 and poles at 104 rad/s and 106 rad/s is incorporated in a negative-feedback loop with feedback factor β. For what value of β do the poles of the closed-loop amplifier coincide? What ...

11.18An op amp having a single-pole rolloff at 100 Hz and a low-frequency gain of 105 is operated in a feedback loop with β = 0.01. What is the factor by which feedback shifts the pole? To what frequency? If ...

11.17If in the circuit in Fig. 11.30(a), R2 is short-circuited, find the ideal value of Af. For the case Rs = Rid = ∞, give expressions for Ri, Ro, A, β, Af, Rin, and Rout. Af = −1 A/A; Ri = ...

11.16For the amplifier in Example 11.10, find the values of Af, Rin, and Rout when the value of μ is 10 times lower, that is, when μ = 100. −9.91 A/A; 921 Ω; 101 MΩ