48.1.3. Calculating Required Values

Try these first

1. 1.

   What is output impedance?

   Hint

   Consider how it affects the load connected to it.

2. 2.

   Define transconductance.

   Hint

   Look for a relationship with inputs and outputs.

3. 3.

   What is the formula for output impedance?

   • R = V/I
   • Output Impedance = 1/gₘ
   • Z = V/I

   Hint

   Look for the formula that includes gₘ.

4. 4.

   True or False: Higher transconductance leads to lower output impedance.

   • True
   • False

   Hint

   Think about the relationship between these two values.

5. 5.

   Design a common drain circuit that can handle an input signal of up to 1V and requires an output impedance of 200Ω. Calculate the necessary transconductance.

   Hint

   Use the output impedance formula to derive gₘ.

6. 6.

   Determine the impact on the cutoff frequency if the load capacitance of a common collector circuit is increased by 50%. What factors play a role in this?

   Hint

   Think about how RC time constant relates to frequency.