*10.85 The transistors in the circuit of Fig. P10.85 have β0 = 100, VA = 100 V, and Cμ = 0.2 pF. At a bias current of 100 µA, fT = 200 MHz. (Note that the bias details are not shown.)
(a) Find Rin and the midband gain.
(b) Find an estimate of the upper 3-dB frequency fH. Which capacitor dominates? Which one is the second most significant?
(Hint: Use the formulas in Example 10.10.)
–2.5 MΩ, –4000 V/V; 107.6 MHz
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