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How to calculate the efficiency of an amplifier e.g. op-amp? Been thinking about that, and have no answer. It should not be Vout / Vin ?
What vk6kro says is correct, what I think you want is called gain. Voltage gain is, as you suggest, calculated from Vo/Vi.So shouldn't be the audio amplifity efficiency more than 1 since its driving power?(generating greater signals)
I know its not, but just dunno how to prove in mathematically. So usually current output is very low although voltage is high? Something like transformer?
Why? What is the point of your question? What amplifier are you working with? What is its power source, its signal source, and what is the load it is driving?Okay, I have reading on those definitions, but no clue of calculating the efficiency of the opamp yet.
Simply, all I need is just an example calculation of the efficiency of an amplifier circuit.
Incidentally, an opamp with a plus 5 and minus 5 volt supply cannot deliver more than plus 4 volts and minus 4 volts out. It cannot deliver more voltage out than it is supplied with and there are drops in the chip that stop it delivering even those voltages.For an example, a non-inverting op-amp. It has +5v and -5v input power supplies. Thus is 10Vx Iin(input current) in power. Say 100mA max current.Power out should be 1W.
If 1V input is given to the inputs of the opamp, with voltage gain configuration of 100, thus output voltage is 100. Say load is 100 ohm. Thus power out should be 100W.
I know this is wrong, but i duno how to calculate in the right way.
Thanks for the guidance and time you all make for me. =)
P.S - must we use root mean square always when calculating power? It means average power right? Why is it always root mean square, and sometimes square root of 3 for 3 phase.. that is another question popping on my head..