48.1.9. Input Capacitance and Impedances

Try these first

1. 1.

   What is the formula for calculating voltage gain?

   Hint

   Think about the relationship between output and input voltages.

2. 2.

   What does the term 'input resistance' refer to?

   Hint

   Identify which part of the circuit affects how the input voltage is seen by the signal.

3. 3.

   What is the approximate voltage gain of a common collector amplifier?

   • 0.5
   • 1
   • 2

   Hint

   Think about the typical behavior of amplifiers in this configuration.

4. 4.

   True or False: Input resistance affects the performance of an amplifier.

   • True
   • False

   Hint

   Consider how much of the input signal manages to enter the transistor.

5. 5.

   For a common collector amplifier, if the resistance of R_E is doubled, how does it affect the input and overall gain?

   Hint

   Use the formulas for input resistance as part of your analysis.

6. 6.

   Calculate the upper cutoff frequency for an amplifier with an output resistance of 600 Ω and Cgs valued at 2 pF.

   Hint

   Be sure to apply the cutoff frequency formula appropriately.