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Topic: Arduino MEGA Pinout Diagram (Read 50 times) previous topic - next topic

xl97

Suggestion:

once you are done.. create a post/thread that has all your work collectively posted?


(maybe even a sticky once done?)  ;)


CrossRoads

Current totals follow the current allowed by the different ports.

3. Although each I/O port can sink more than the test conditions (20mA at VCC = 5V, 10mA at VCC = 3V) under steady state
conditions (non-transient), the following must be observed:

ATmega640/1280/2560:
1.)The sum of all IOL, for ports J0-J7, A0-A7, G2 should not exceed 200 mA.
2.)The sum of all IOL, for ports C0-C7, G0-G1, D0-D7, L0-L7 should not exceed 200 mA.
3.)The sum of all IOL, for ports G3-G4, B0-B7, H0-B7 should not exceed 200 mA.
4.)The sum of all IOL, for ports E0-E7, G5 should not exceed 100 mA.
5.)The sum of all IOL, for ports F0-F7, K0-K7 should not exceed 100 mA.
If IOL exceeds the test condition, VOL may exceed the related specification. Pins are not guaranteed to sink current greater
than the listed test condition.

That totals 800mA. There is nothing that says if you draw 200mA in one group that you then can't draw it in another.
So this thinking of only 200mA total is nonsense.

Similar numbers apply to the 328 & 1284.
Designing & building electrical circuits for over 25 years. Check out the ATMega1284P based Bobuino and other '328P & '1284P creations & offerings at  www.crossroadsfencing.com/BobuinoRev17.
Arduino for Teens available at Amazon.com.

retrolefty

#17
Feb 04, 2013, 03:01 am Last Edit: Feb 04, 2013, 03:06 am by retrolefty Reason: 1
Quote
That totals 800mA. There is nothing that says if you draw 200mA in one group that you then can't draw it in another.
So this thinking of only 200mA total is nonsense.


LOL, we've had this same discussion before.

Quote
There is nothing that says if you draw 200mA in one group that you then can't draw it in another.


There is also nothing stating that you can take the sum, of all those individual port limits, as the maxiumum chip current draw limit. And no where in the datasheet does it state that 800 ma of total current draw is allowed. And of course as I've stated before the absolute maximum section lists the 200 ma figure. Why would they state 200ma there if it only applied to one port? Your assumption, and it is just an assumption, is in error, IMHO.

But that is why I would like others to comment on the subject, as you and I. while still respectful of each other's opinion, have not been able to come to consensus on the matter now or in the past.

Lefty

CrossRoads

They state the Vcc and Gnd PinS are 200mA. Do you suppose they use wimpier wire in a 2560 vs a 328 so that only 200mA is allowed? I think not.
Designing & building electrical circuits for over 25 years. Check out the ATMega1284P based Bobuino and other '328P & '1284P creations & offerings at  www.crossroadsfencing.com/BobuinoRev17.
Arduino for Teens available at Amazon.com.

pighixxx

ATMega 2560 Pinout is on line on first post.
New version of Arduino MEGA.

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