9.2.3. Equivalent Circuit Models

Try these first

1. 1.

   Define a BJT.

   Hint

   Think of how BJTs are categorized.

2. 2.

   What does the β (Beta) represent in BJTs?

   Hint

   Consider the relationship between input and output currents.

3. 3.

   What does β represent in a BJT?

   • Current gain
   • Voltage gain
   • Power gain

   Hint

   Remember it’s related to current ratios.

4. 4.

   True or False: The I-V characteristics of all BJTs are identical regardless of type.

   • True
   • False

   Hint

   Think about the configuration of the transistors.

5. 5.

   Design a circuit using an n-p-n transistor model where β=100, and I_B is set to 0.1 mA. Evaluate I_C and determine the collector-emitter voltage drop if it is 10V.

   Hint

   Start with applying the formula for current gain, and evaluate the drop accordingly.

6. 6.

   If a p-n-p transistor has a β of 30 and an emitter current (I_E) of 15 mA, calculate the base current (I_B) and collector current (I_C).

   Hint

   Use relationships among I_C, I_B, and I_E to solve.