63.6.1. Output Voltage Gain Calculation

Try these first

1. 1.

   Define a cascode amplifier.

   Hint

   Think about the structure of the circuit.

2. 2.

   What is the formula for collector current in terms of base current?

   Hint

   β is the transistor's current gain.

3. 3.

   What is the typical function of a cascode amplifier?

   • To decrease voltage gain
   • To improve bandwidth
   • To provide isolation

   Hint

   Consider the advantages of multi-stage amplifiers.

4. 4.

   True or False: The collector current is influenced by the base current and the transistor's beta.

   • True
   • False

   Hint

   Review the relationship between different currents in a transistor.

5. 5.

   Given a BJT cascode amplifier with a supply voltage of 15 V, β for the first transistor is 150, and a load resistance of 2 kΩ, calculate its output voltage if the input voltage is 0.5 V and β for the second transistor is 180.

   Hint

   Start by finding I_C for both transistors first.

6. 6.

   Discuss implications of increasing the Early voltage in a cascode amplifier—how would it alter performance metrics?

   Hint

   Think about how output behavior changes with variations in supply voltage.