61.1.2. Input Impedance

Try these first

1. 1.

   What does input impedance represent in an amplifier?

   Hint

   Think about the relationship between a signal and what it sees in the circuit.

2. 2.

   Name an advantage of using a cascode amplifier.

   Hint

   Consider why certain configurations are preferred in signal processing.

3. 3.

   What is the primary benefit of a cascode amplifier?

   • Higher input capacitance
   • Higher output impedance
   • Lower power consumption

   Hint

   Think about impedance and how it impacts performance.

4. 4.

   True or False: The Miller effect always increases input capacitance.

   • True
   • False

   Hint

   Remember the impact of gain on capacitance.

5. 5.

   Design a cascode amplifier circuit using specific transistor parameters, and analyze how variations in R2 and R3 impact output voltage.

   Hint

   Sketch the circuit and analyze the interaction of resistors systematically.

6. 6.

   In a cascode amplifier, if you wanted to achieve an effective input capacitance of below 5pF with specific transistor configurations, what parameters would you tweak?

   Hint

   Consider the target value and how capacitor values correlate with known equations.