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I have a very basic doubt. If we have an amplifier with voltage gain A = Vo/Vi , where Vo is output and Vi is input voltages and Ap = Po/Pi which is power gain.

Ap = Po/Pi = Vo^2/Vi^2 = (Vo/Vi)^2

In decibels powergain = 10 log (Po/Pi) = 20 log (Vo/Vi).

In most tech literature 20 log(Vo/Vi) is addressed as voltage gain in decibels and not power gain in decibels. Why is it so?

Actually 20 log(Vo/Vi) is power gain in decibels. Right...

-Devanand T

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# Confusion in Power gain and voltage gain in decibels

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