28.2.5. Saturation Region Discussion

Try these first

1. 1.

   What is the collector current for a fixed bias amplifier when the base current is 20 µA and beta is 100?

   Hint

   Use the formula I_C = β * I_B.

2. 2.

   Define a fixed bias configuration.

   Hint

   Think about how the bias point is determined.

3. 3.

   What is the primary disadvantage of fixed bias?

   • Stable at all times
   • Sensitive to beta changes
   • Economical in design

   Hint

   Think about the impact of beta variations.

4. 4.

   True or False: A cell biased amplifier is less dependent on beta stability than a fixed bias amplifier.

   • True
   • False

   Hint

   Consider how cell biasing works.

5. 5.

   Design a fixed bias configuration for a common emitter amplifier expecting beta to vary between 100 and 200. Discuss how to prevent distortion.

   Hint

   Consider how to account for changing beta in your design.

6. 6.

   Given a BJT's transfer characteristics, predict how changes in the biasing methods will shift the Q point and impact signal amplification.

   Hint

   Reference the graphs of saturation and active regions.