August 2020 StudentZone Quiz Solution

Question 1:

Can you name one advantage and one disadvantage for the current mirror circuit with base current compensation?

Advantage:

• Reduce the gain error caused by the finite base currents

Disadvantage:

• Loss in the frequency response of the mirror

Question 2:

Can you name one advantage and one disadvantage for Wilson Current Mirror?

Advantage:

• Eliminate the base current mismatch of the conventional BJT current mirror thereby ensuring that the output current is almost equal to the reference current. It also has a very high output impedance due to the negative feedback.

Disadvantage:

• Minimum allowed input and output voltages are relatively large; drain-source voltages of the two main current mirror transistors are not equal