Calculate the Small Signal Voltage Gain
a) Calculate the small signal voltage gain av = vo/vi , input resistance Ri , and output resistance Ro for the circuit below. Assume the circuit is biased such that VO = Vcc/2.
Note: since RL -> ∞ in this example, the approximation ro >> RL does not hold! See the textbook or posting "Approximations" on the course web for more on this.
b) Verify your result with a circuit simulator. Submit a printout of the schematic diagram(or netlist), the output from the operating point analysis (mark the bias point values with a red box), and the output from the DC transfer function analysis. Comment on any discrepancies in excess of 10% between your hand analysis and the simulation.
Suggestions: Model IBias with an ideal current source and check "models an active current source" under the advanced tab. This prevents Vo from reaching kV during the DC sweep analysis. The the LTSpice document on the course website shows an example of a DC transfer function analysis.
Use Vcc = 5V, IBias = 100 μA, RE = 2 kΩ, RL -> ∞, Is = 1 fA, β = 100, and VA = 100V.