# Micro controller power calculation

Discussion in 'Microcontrollers, Programming and IoT' started by Abhinav, Aug 9, 2016.

1. ### Abhinav

11
0
Aug 8, 2016
I have heard people talking about the power calculation of a device and mostly micro controller.

I haven't obtained much clarity on that.

Please give me an Explain to understand a bit more clearly.

Suppose, I have a microcontroller and few peripherals.
Input to the microcontroller is +5V and there are 3 peripherals which require a voltage and a load current of 3V 5A,5V 3A and 3V 2A respectively.

And by the way, can a device have a high requirement of load current than its input voltage ?
Ex. Can a device have a rating like 2V and 3A load current ( Where the load current is greater than the input supply voltage ? )

2. ### BobK

7,682
1,686
Jan 5, 2010
To get power, multiply the voltage by the current. So, in your example:

3V 5A = 15W
5V 3A = 15W
3V 2A = 6W

A typical microcontroller uses microwatts to milliwatts of power, not as high as 1W.

Can a device take 2V and 3A? Why not? That is like asking if an object 10 inches long can weight more than 10 pounds. You cannot compare Volts to Amps, they are entirely different things.

Bob

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