I would like to know the electric current flow in Arduino . It goes from 5V or 3V to gnd?
Regards,
Jorge Monteiro
What you are asking is very unclear. You sound like you need a lot more basic understanding of electronics. If an arduino is operating at 5V, as most are... it will be using 5V at the pins, and be using 5 volts for signaling making complete circuits... like light an LED.
If it is using 3.3V... then 3.3V signalling applies. You CAN use the 3.3V Source to assist in connecting a 5V arduino to a 3.3V logic board. Sadly, it is some what confusing that some things run at 5V and some things run at 3.3V.
Current flows when there is a potential (voltage) difference and a completed circuit path. If there is a valid "closed" path between something at 5V potential and gnd potential... it will be a circuit.
This is a circuit. It doesn't matter if it's 5V or 3V, a closed path exists... so current will flow.
Maybe you need to ask your question 1 more time. Adding more detail.
The arduino by itself draws about 51 mA , running on 5V, so it is equivalent to a 100 ohm load resistor across a 5V battery source. This is approximately P = I*V = 0.051 A * 5V =0.255W ~ 1/4W.
0.255 W /3.3V = 0.0772 A = 77.2 mA @ 3.3V
It goes from 5V or 3V to gnd?
If there's nothing else connected, yes.
But for example if you are running an LED, some of current flowing into the Arduino will come out* of an output pin and through the LED to ground, instead of coming out of the Arduino's ground.
The total current flowing out of the power supply (or battery) has to equal the total current flowing back in. But, there can be many parallel current paths.
*Depending on how the LED is wired, the current may flow onto an I/O pin (and out of the Arduino's ground). In this case, we say the I/O pin is "sinking" current. When current flows out, we say it's "sourcing" current.
P.S.
There's one thing you should be aware of... When you study electronics, you'll learn that "conventional current" flows from positive to negative. But if you study science, you'll learn that electrons actually flow from negative to positive. Conventional current is just a convention or tradition, but it's what everybody in engineering uses. And if you look at a schematic symbol for a diode or transistor, the arrow points in the direction of conventional current flow... The "engineering way".
Thanks all for the information.
If it helps remember that current is the flow of charge, not electrons or anything else that
carries charge. Since the electron charge is by convention negative, electrons flow in the opposite
direction to charge flow.
In an anti-matter world the charge in an anti-wire would be of positrons, which are positively
charged.
MarkT:
... In an anti-matter world ...
Outside of Larry Niven short stories, do those exist?
Yes they do. A few years ago they made an anti molecule of hydrogen. That is about as far as we have done.
Just a tip. If you think the direction of current matters then you are misunderstanding something fundamental.
Grumpy_Mike:
Just a tip. If you think the direction of current matters then you are misunderstanding something fundamental.
I like that.
ChrisTenone:
Outside of Larry Niven short stories, do those exist?
I think we'd know if they (antimatter worlds, not just antimatter molecules) did, because we'd see really freakin' bright flashes of gamma radiation when a chunk of condensed matter hit a chunk of condensed antimatter...
DrAzzy:
I think we'd know if they (antimatter worlds, not just antimatter molecules) did, because we'd see really freakin' bright flashes of gamma radiation when a chunk of condensed matter hit a chunk of condensed antimatter...
Not sure it is anywhere near that simple.
Consider the electron. And the proton.
The electron is negatively charged, the proton is positively charged; they attract each other.
Well, why do electrons not simply lose all their angular velocity and join the proton? But they don't!
Why would things be different with matter and antimatter?
Orbital angular momentum or spin angular momentum? Some orbitals have zero angular momentum.
Antimatter has a high amplitude to react with matter and generate radiation, electrons and protons
generally don't react (just attract) and the orbital size is determined by Heisenberg's principle - confinment in
position requires higher momentum uncertainty, which means more energy - but the electrostatic
attraction can only provide so much energy to stabilise an orbital. See Schroedinger's/Diracs's equations for
a more accurate quantum treatment - atomic orbitals are only really explanable in quantum terms.
Electrons and protons can react in some unstable nucliei via the weak force: Electron capture - Wikipedia
The hall effect can be used to determine the true polarity of mobile charge. In reality, the direction of flow really does matter. For stuff going on in this forum, it doesn't.
In reality, the direction of flow really does matter.
No it doesn't not even in solid state physics. As long as you are consistent direction of current flow is simply irrelevant.
You are mixing up current with flow of electrons and holes, but it really doesn't matter.
Could you give an example of where you think it matters?
Grumpy_Mike:
Could you give an example of where you think it matters?
Hall effect. I am repeating myself. But if you know the polarity of mobile charge there is only one direction for the charge to flow. That is the real physics. You can do a double inversion and say the result is the same but that does not describe the real physics.
Please explain how the direction of current flow does not matter to the polarity of the hall voltage. It does.
That is the real physics.
I would dispute that.
The same thing works if you consider charge moving in the opposite direction and the interaction of charge and a magnetic field.
You can do a double inversion and say the result is the same but that does not describe the real physics.
Yes it does.
Physics is all about making models that match the observations observed.
If everything were inverted, that is we had an antimatter universe, everything would work exactly the same and we would never know.
In fact if I said we were living not in a matter universe buy an antimatter universe there would be no argument that could be made to prove or disprove that. It is all arbitrary, there are no absolutes.
But I suppose you not being a physicist you are going to find that hard to believe.
Grumpy_Mike:
I would dispute that.
The same thing works if you consider charge moving in the opposite direction and the interaction of charge and a magnetic field.
You do not understand the hall effect. You are mistaken.