Question Related to Class A Power Amplifier

[sweetchoto]

Dear All,

I have the following question Related to the Class A amplifier. I hope that i will get useful hint, ideas or solutions over here. The question and the conditions are as follows:

The input level of a class A amplifier can be increased further than usual until the current waveform clips on two sides.

•Assume the curent waveform to be a square wave with 50% duty cycle.

•Harmonics are taken care of in a way that both the load voltage and the voltage across the transistor are sinusoidal.

•Calculate the output power and efficiency of this mode of operation in relation to class A operation.


Looking forward to hear from you guys how to Calculate output power and Efficiency in this case.

BR,
SC

 

[BradtheRad]

It's hard to figure out what you're getting at.

Don't know if you mean it hypothetically, turning a square wave into sinusoidal.

Are you hoping to find a way to operate in class A, without heating up the transistor?

Class A operation means the amp runs at average 50% efficiency, whatever the waveform.

There will be a certain point near the center of the operating range where power dissipation is greatest. The curve is bell-shaped. I don't know if the high point is exactly at center of operating range, or above or below.

However you mention driving the amp to clipping. When this happens you're operating it partially as a switch. Sometimes full on, sometimes full off. This reduces power dissipation. But then you don't have sinusoidal waveform coming from the transistor.

Do you mean the input is a square wave but it doesn't drive the amp to clipping? A square wave riding a DC component?