75.4.2. Finding Common Mode Gain

Try these first

1. 1.

   What does A_d represent in a differential amplifier?

   Hint

   Think about what differential amplifiers are designed to amplify.

2. 2.

   Why do we want A_c to be as small as possible?

   Hint

   Consider what would happen if noise were amplified.

3. 3.

   What is the ideal relationship between A_d and A_c in a differential amplifier?

   • A_d should be high and A_c should be low
   • A_d and A_c should be equal
   • A_d should be low and A_c should be high

   Hint

   Recall the basic objectives of a differential amplifier.

4. 4.

   The differential mode gain (A_d) is primarily affected by what aspect of the amplifier?

   • True
   • False

   Hint

   Think about what signals A_d serves to amplify.

5. 5.

   A differential amplifier with components not matched leads to unexpected behavior at the output. Propose a solution to ensure performance remains robust despite variations.

   Hint

   Consider methods for stabilizing output against component mismatch.

6. 6.

   An engineer needs to design a differential amplifier achieving A_d of 2000 while keeping A_c under 5. What design considerations may help achieve these goals?

   Hint

   Think about component characteristics and their effects on gain.