Amplifier efficiency calculations?

AI Thread Summary
Calculating amplifier efficiency using the formula P output/P input x 100 does not yield the same results as using RMS input and output values. Efficiency is defined as the power delivered to a resistive load divided by the DC power supplied to the amplifier, expressed as a percentage. The power into the resistive load is derived from the AC voltage across that load. In contrast, the power supplied to the amplifier is calculated by multiplying the DC supply voltage by the DC current flowing through the transistors. Understanding these distinctions is crucial for accurate efficiency calculations in amplifiers.
MehhShell
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Would the efficiency calculated using the P output/P input x 100 get the same answer as calculating the efficiency using the RMS input and output values? If so why?
 
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No, it isn't the same.

Efficiency is the power out into a resistive load divided by the DC power into the amplifier, multiplied by 100 to get percentage.

The power into the resistive load is usually caused by an AC voltage across the load.

The power into the amplifier is the (DC supply voltage) times the (DC current) supplied to the transistors in the amplifier.
 
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