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Power Amplifier Voltage & Current Level

Hi,

How do you calculate the output voltage of a particular power amplifier model? They are most rated in watts such as

750W @ 4 ohm load.

I build a function generator using the IC XR2206. It's current is so low I can't even drive a bulb of light with it. So I plan to boost the voltage and current by plugging it to a power amplifier. I need a voltage

10V or above. I wonder what is the average voltage rating of a power amplifier. Is it dependent on the wattage or power rating? How do I know its respective voltage and current?

Thanks.

Lory

Reply to
Lory
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Do you actually want to vary a light bulb's intensity or are you using that as an example? Since you built the generator you may like to look up some of the amplifier IC's that are available, such as the LM386.

Ken

Reply to
Ken Taylor

The power to a load can be calculated with voltage and resitance values with equation

power = (U * U) / R

Where U is the voltage and R is the resistance

This becomes U = sqrt( power * R) In this case the voltage with 750W @ 4 ohm load would be around 54.8 V. That's the RMS voltage. The peaks go to around +-77V.

That's a good idea. A normal audio amplifier works well with function generator as long as you work within the frequency response of the amplifier.

The amplifier you have can definately give that.

I answered those in the example above.

--
Tomi Engdahl (http://www.iki.fi/then/)
Take a look at my electronics web links and documents at 
http://www.epanorama.net/
Reply to
Tomi Holger Engdahl 

--
Since when is voltage "U"?
Reply to
John Fields

Since Urope started using it. Pretty soon all electrical products shipped to Urope will have to Uoltage ratings specified.

--

    Boris Mohar
Reply to
Boris Mohar

V haue to be kidding!

Ken

Reply to
Ken Taylor

Dependign on what books or other references you read you can see letters U, E and V used to mark voltage on the equations.

--
Tomi Engdahl (http://www.iki.fi/then/)
Take a look at my electronics web links and documents at 
http://www.epanorama.net/
Reply to
Tomi Holger Engdahl

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