- 24th May 2007, 07:58 #1

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## ac power consumption calculation

If I have a number of op-amps on a circuit, how do I calculate the power consumption? Do I consider only the quiescent current?

Thanks,

Eric

- 24th May 2007, 07:58

- 26th May 2007, 11:27 #2

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## how to calculate ac power consumption

it depends on the circuit u r using.... in dc it is easy but when the signal or intermediate signals are ac then the power consumption will vary.... in dc the current supplied by the power supply can be used to easily find the power consumption...

- 26th May 2007, 15:06 #3
## calculate ac power consumption

Connect a ammeter in series with the circuit and measure the current. Measure the supply voltage. Multiply current and voltage to calculate power consumption.

- 26th May 2007, 15:06

- 27th May 2007, 17:55 #4

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## calculate power consumption

dc power dissipiation will be higher than that of ac, since usually the ac voltages are very less even at the output.

to find your output power dissipiated, measure the voltage across which you take the output and multiply it by the current flowing through the output terminal.

- 28th May 2007, 12:00 #5

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## circuit power consumption calculation

If the supplies are same to all the opamps simply measure the voltage and current across the maiin supply. multiply them to get the power. AC part i think u can neglet it.

- 29th May 2007, 09:15 #6

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## how to calculate power consumption of ac

do u know to operate multimeter? Then it is easy to measure. Normally there is ampere measuring included in multimeter. U can then check the operating manual of multimeter & it will show how to measure current.

Then voltage x current = watts.

- 2nd June 2007, 17:50 #7

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## how to calculate power consumption

By measuring the currents and voltages you are not calculating the power consumption. I think the easiest way to calculate the power consumption is by detailed analysis of the various circuit elements. If a simulator is available this might be suitable for your purposes.

Cheers

Slayer