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Arduino Mega 2560 r3 - Power Consumption
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Arduino Mega 2560 r3 - Power Consumption

by RobertoBomfim on Fri Sep 25, 2015 10:00 am

Hey there!

I couldn't find anything about power consumption of the Arduino Mega 2560 r3.

Where can I find this information? I want to know the power consumption considering that no I/O is being used, just the Microcontroller and the board. Something like MIN/TYP/MAX power consuption would be enough ; ).

Thank you very much!

RobertoBomfim
 
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Re: Arduino Mega 2560 r3 - Power Consumption

by adafruit_support_mike on Fri Sep 25, 2015 2:30 pm

With no pin IO, you can expect a current load between 50mA and 75mA. The chip has an upper limit of 200mA for all processing and IO combined, and there are low-power sleep modes that only draw a few microamps.

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Re: Arduino Mega 2560 r3 - Power Consumption

by RobertoBomfim on Mon Sep 28, 2015 10:11 am

Thanks for your answer Mike!

As you pointed out, session "31. Electrical Characteristics" of the ATmega2560 datasheet establishes this 200 mA of maximum current between VCC and GND (this limit comprises processing + all the I/Os).

I know I haven't explained it in my fisrt post, but my goal is to specify a power supply to be used with the Arduino Mega 2560 r3 board.

So, thinking of the whole board, including anything that could drain power directly from the board's voltage regulator (as a generic shield or an LCD), maybe I should consider the maximum current the voltage regulator is able to output (1000/1500/2200 mA, MIN/TYP/MAX) as a specification to my power supply.

Do you agree with me?

Thank you again!

RobertoBomfim
 
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Joined: Fri Sep 25, 2015 9:50 am

Re: Arduino Mega 2560 r3 - Power Consumption

by adafruit_support_mike on Tue Sep 29, 2015 12:24 am

Spec'ing a power supply without a power consumption table is like trying to estimate gas mileage without deciding what kind of vehicle you'll use or how much load you'll be hauling.

If you want to power the Mega through the USB port, you're limited to 500mA by a polyfuse on the USB-5v line. If you use the DC barrel jack you'll need at least 6.5v for the NCP117's dropout voltage, and will then be limited to 1.5A for power supplies below 12v, but at 12v and up you want to stay below 1A or you'll risk overheating the regulator. If you use an external regulator and connect it to the Mega's 5v pin, you can have any current limit you want, but the board per se will only consume 50ma to 75mA or the microcontroller per se, plus whatever current load the associated shields will have.

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Please be positive and constructive with your questions and comments.