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Is op amp or any amplifier circuit/device a over-unity device?

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Pagedown
#1
Jan20-11, 11:47 PM
P: 92
Is op amp or any amplifier circuit/device a over-unity efficient device?

The above question has been stuck in my mind, and I can't figure it out, as Vout is greater than Vin which Pin>Pout. So is it?

I heard alot about free energy and aether, thus come to this question.
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yungman
#2
Jan21-11, 12:15 AM
P: 3,883
Do you mean over 100% efficiency? Absolutely not. If there is one, I want one too!!!

Or are you just talking about voltage gain?
Pagedown
#3
Jan21-11, 12:33 AM
P: 92
the efficiency. So how to calculate its efficiency, if it is not Vout/Vin since it is voltage gain?

yungman
#4
Jan21-11, 12:36 AM
P: 3,883
Is op amp or any amplifier circuit/device a over-unity device?

I am confuse how do you define efficiency? I am confused. To me, efficiency means power out divid by power in times 100 percent. Nothing even come close to 100%. Power in include the driving power plus the power input from the power supplies.
Pagedown
#5
Jan21-11, 12:40 AM
P: 92
So power in should be the Voltage IN while power out should be Voltage OUT? I am confused how to calculate it. Maybe although the voltage gain is high, the output current is very low? I do know that is true for transformers, but dunno for any opamp or semiconductor.
berkeman
#6
Jan21-11, 01:18 AM
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Quote Quote by Pagedown View Post
Is op amp or any amplifier circuit/device a over-unity efficient device?

The above question has been stuck in my mind, and I can't figure it out, as Vout is greater than Vin which Pin>Pout. So is it?

I heard alot about free energy and aether, thus come to this question.
I will put this as gently as I can.

The big giant battery or the wall power plug is where the "extra" energy comes from for power amplifiers. There is no free energy.

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russ_watters
#7
Jan21-11, 06:18 AM
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P: 22,234
Quote Quote by Pagedown View Post
So power in should be the Voltage IN while power out should be Voltage OUT? I am confused how to calculate it. Maybe although the voltage gain is high, the output current is very low? I do know that is true for transformers, but dunno for any opamp or semiconductor.
Just to add one thing: voltage is not power. Wattage is power.


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