Question: 910 for the circuit in fig 918 let i ...
9.10 For the circuit in Fig. 9.18, let I = 1 mA, VCC = 15 V, RC
= 10 k, with α = 1, and let the input
voltages be vB1 = 5 + 0.005 sin 2π × 1000t, volts, and vB2 = 5 − 0.005 sin 2π × 1000t, volts. (a) If
the BJTs are specified to have vBE of 0.7 V at a collector current of 1 mA, find the voltage at the
emitters. (b) Find gm for each of the two transistors. (c) Find iC for each of the two transistors. (d)
Find vC for each of the two transistors. (e) Find the voltage between the two collectors. (f) Find the
gain experienced by the 1000-Hz signal.
Ans. (a) 4.317 V; (b) 20 mA/V; (c) iC1 = 0.5+0.1 sin 2π × 1000t, mA and iC2 = 0.5 – 0.1 sin 2π ×
1000t, mA; (d) vC1 = 10 – 1 sin 2π × 1000t, V and vC2 = 10 +1 sin 2π × 1000t, V; (e) vC2 – vC1 =
2 sin 2π × 1000t, V; (f) 200 V/V
CAN YOU SHOW THE WORKING?