7.1.2. Revisiting BJT Characteristic

Try these first

1. 1.

   What are the three terminals of a BJT?

   Hint

   Think of the structure and name the parts you see.

2. 2.

   Define forward bias in a BJT.

   Hint

   Consider which direction you want the current to flow.

3. 3.

   What is the primary current flow direction in the BJT when the base-emitter junction is forward biased?

   • From emitter to collector
   • From collector to emitter
   • None of the above

   Hint

   Think about where charge carriers originate.

4. 4.

   True or False: The base-collector junction in a BJT is typically forward biased during normal operation.

   • True
   • False

   Hint

   Consider what conditions are needed for current to flow.

5. 5.

   Analyze a BJT circuit where the base current is 20 µA, and the current gain (β) is 100. What is the expected collector current?

   Hint

   Remember the relation of current gain in BJTs.

6. 6.

   Given a BJT with a V_BE of 0.7V and a collector saturation current (I_S) of 10 nA, calculate the collector current at room temperature (approximately 25°C).

   Hint

   Still using the diode equation, keep an eye on exponential growth!