Q5Analog Circuits

The efficiency of a Class A amplifier is highly dependent on how close the output voltage swing approaches the supply rails. The maximum theoretical efficiency is $50\%$ for a transformer-coupled load.

Given parameters: - Maximum collector-emitter voltage, $V_{max}=20\text{ V}$ - Minimum collector-emitter voltage, $V_{min}=4\text{ V}$ - Supply voltage, $V_{CC}=25\text{ V}$

The overall efficiency ($\eta$) for a transformer-coupled Class A amplifier based on the peak-to-peak voltage and current swings can be derived as:

Substituting the given voltage values into the formula:

The overall efficiency of the amplifier is 33.33%.