*9.110 Figure P9.110 shows a bipolar op-amp circuit that resembles the CMOS op amp of Fig. 9.37. Here, the input differential pair Q1–Q2 is loaded in a current mirror formed by Q3 and Q4. The second stage is formed by the current-source-loaded common-emitter transistor Q5. Unlike the CMOS circuit, here there is an output stage formed by the emitter follower Q6. The function of capacitor CC will be explained later, in Chapter 11. All transistors have β = 100, |VBE| = 0.7 V, and ro = ∞.
(a) For inputs grounded and output held at 0 V (by negative feedback, not shown) find the emitter currents of all transistors.
(b) Calculate the gain of the amplifier with RL = 1 kΩ.
0.2 mA, 0.2 mA, 0.2 mA, 0.2 mA, 0.25 mA, 0.5 mA; 1.61 × 105 V/V
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