64.6.2. Practical Applications

Try these first

1. 1.

   What is a cascode amplifier?

   Hint

   Think about the arrangement of transistors.

2. 2.

   What does transconductance measure?

   Hint

   It's related to the input-output voltage relationship.

3. 3.

   What is the primary benefit of a cascode amplifier?

   • Lower output resistance
   • Higher gain
   • Higher input capacitance

   Hint

   Consider what is specifically improved in this amplifier type.

4. 4.

   True or False: Increasing output resistance of a cascode amplifier generally leads to higher bandwidth.

   • True
   • False

   Hint

   Reflect on the trade-offs discussed earlier.

5. 5.

   A cascode amplifier shows a gain of 50, but the input capacitance is causing concern. If the output stage resistance is increased, predict the impact on bandwidth and justify.

   Hint

   Use the relationship between capacitance and frequency response.

6. 6.

   Design a cascode amplifier with a target gain of 200 and analyze how varying the input resistance affects overall performance.

   Hint

   Exploit the gain relationship while keeping resistance in mind for your calculations.