51.1.6. Input Impedance Calculation

Try these first

1. 1.

   Define input impedance in your own words.

   Hint

   Think about how resistance works with electric signals.

2. 2.

   What is the primary role of a common base amplifier?

   Hint

   Consider where the input and output terminals are located.

3. 3.

   What is the main purpose of a common base amplifier?

   • To increase current
   • To increase voltage
   • To decrease impedance

   Hint

   Consider what is typically measured in amplifiers.

4. 4.

   True or False: Input impedance in a common base amplifier is generally high.

   • True
   • False

   Hint

   Remember how this type of amplifier operates.

5. 5.

   Consider a common base amplifier with a source resistance of 10k Ohms, and an input impedance of 26 Ohms. What would be the expected impact on output voltage?

   Hint

   Use concepts from voltage division to guide your analysis.

6. 6.

   Design an amplifier circuit aiming for a gain of 50 with the lowest possible input impedance. What components would you select?

   Hint

   Use the voltage gain formula and consider the importance of bypass capacitors.