75.4.1. Finding Differential Mode Gain

Try these first

1. 1.

   What is differential mode gain?

   Hint

   Think about the definition regarding output and input signals.

2. 2.

   What does common mode gain refer to?

   Hint

   Consider signals that are the same at both inputs.

3. 3.

   What is the primary function of a differential amplifier?

   • To amplify a single input signal
   • To amplify the difference between two signals
   • To provide rectification

   Hint

   Focus on the key function of the device.

4. 4.

   True or False: The ideal differential amplifier aims for both high differential mode gain and high common mode gain.

   • True
   • False

   Hint

   Think about the characteristics discussed in class.

5. 5.

   Design a differential amplifier circuit using BJTs to achieve a targeted differential mode gain of 10. Calculate the necessary component values if the output voltage is expected to be 5V.

   Hint

   Use the formula Ad = Vout / Vin,d.

6. 6.

   Given a common mode signal of 1V at both inputs of a differential amplifier, explain its effect on the output if the common mode gain is found to be significant.

   Hint

   Consider how Ac affects unity output in common signal scenarios.