For what purpose is an active load used in the collector of the difference amplifier of an Op-amp?
For what purpose is an active load used in the collector of the difference amplifier of an Op-amp? Correct Answer To increase the differential gain
In the differential amplifier of an op-amp, when the active load is used in the collector by replacing the resistive load for the following purpose:
i) to increase the differential gain
ii) to improve the common-mode rejection ratio (CMRR)
iii) active load provides large AC resistance
So the correct answer is option 2.
Important points:
Differential amplifier:
A differential amplifier is an arrangement of transistors such that it amplifies the difference between the signal and it is proportional to the output.
It can be operated in three modes:
i) Single-ended mode: only one input is available and the other is grounded.
ii) Differential mode: Signal is applied to both input with the same magnitude and frequency but 180° out of phase
iii) Common mode: Signal is applied to both input with the same magnitude and phase and frequency