Question

11.41 O The circuit of Fig. P11.41 represents the inter- nal circuitry of a simple BJT operational amplifier. In answering the following questions, use appropriate en- gineering approximations where required. Assume the BJTs in the circuit to be matched and to have the fol- lowing parameters: Cli = 1 pF, VA 00, VBE = 0.7 V, Vsat 0.2 V,尾= 200, and η = 1 . Find the bias currents through each BJT and the bias voltages of nodes A, B, C, D, E, and voUT. Compute the midband gain, small-signal output resistance, and differential-mode input resistance of the amplifier.

Answer 1

BE DC ii) oc 8.3k Rtdz 20.2 K 435 2-3.3c v 5.05 V BEON オ E ν' Dc. 39

2 Ez -3.361 vdd CM v Vout m d band pip ank.dmoed, tina- thee etbedne sitnikad AYん Ao

amg in So, at Gn フ) 込. 0.2 474 Sicmy 2.5

2. 52,So.S7 = 944dB RS, 2S 21 R. 0 R G 25 mv Rid id 200 = 100 z 20.2.1 rur