5.3. Transfer Characteristics

Try these first

1. 1.

   Define the term 'Current Gain' in the context of BJTs.

   Hint

   Think about how much the small base current can control a larger output.

2. 2.

   What is the primary function of the base current in a BJT?

   Hint

   Relate this to amplification or switching in circuits.

3. 3.

   What is the relationship between base current and collector current in a BJT?

   • They are equal.
   • They are inversely proportional.
   • Collector current is larger than base current.

   Hint

   Consider how small signals control larger outputs.

4. 4.

   True or False: The transfer characteristics of a BJT are linear across all current levels.

   • True
   • False

   Hint

   Think about the amplification behavior graph.

5. 5.

   Design a simple circuit using a BJT as a switch for an LED. Given a 12V supply and a base current of 2 mA, determine the maximum collector current you can expect if β = 120.

   Hint

   Use the relationship between base current and collector current.

6. 6.

   Explain how the transfer characteristics of a BJT would change if it's overheating. What practical steps could you take in circuit design to handle this?

   Hint

   Consider how temperature affects semiconductor behavior.