OK, I was reviewing diodes (Elementary level here ) and I am lost as to what direction electrons actually flow in a DC circuit. Checked out a youtube video and the first video that I decide to watch says + to -. Read the first ten comments and the commentators were ripping the guy apart for showing the electrons flowing in the wrong direction.
Another issue that brought this matter up for review was diodes where I thought they described flow in the wrong direction. My question was how can you push electrons through the diode backwards if they do not flow that direction. Can you just flip the diode around and then they will simply flow in the other direction? Seems silly, but I am no EE.
Hope this is not a point of theoretical contention in the field of EE for a thread of war, but I simply do not know after all of this. I sure thought this matter was EE 101 and already solved. Thanks for any help.
I have seen a lot of folks get wrapped around the axle by the "conventional flow" and "electron flow" methods. I hope I can clarify your understanding.
First of all, you and everyone else should not use the technical slang term "current flow". Current already means charge flow, so that slang term really means "charge flow flow", which is redundant and ridiculous. You should instead say current exists or current is present, and be syntactically correct. Even when everyone knows what you mean, slang obfuscates a meaningful description. You are a student, not a poet.
Realize that there are just as many positive charges in the universe as negative charges. Blaming Ben Franklin, switching the names of the charges, or redefining the direction they move in an electric field is not going to help your confusion.
Although it is not usually not emphasized, the conventional flow method is a
mathematical method or procedure which dictates that positive charges will flow from the positive terminal of the voltage source through a conduction path, and into the negative terminal. It makes no distinction about the polarity of the charge carrier.
You will get yourself into big trouble and confusion if you approach a problem by first asking, "Are the charge carriers positive or negative"? And then start to write Kirchoff's equations based on the answer. The bullet proof method is to first assume that the unknown currents are composed of positive charges. Then, if you need to really know the true direction of the charge carriers, keep the same direction if the carriers are positive, like holes are, and reverse the direction if they are negative, like electrons are. Works every time.
By the way, you have probably observed that semiconductor manufacturers have adopted the mathematical convention to mark their devices. So have manufacturers of ammeters. So when you put a positive voltage on the positive terminal of an ammeter, it is going to deflect the needle to the right indicating a forward direction. But since you know that electrons are negative charge carriers, you can deduce that the physical direction of the electrons are in the opposite direction. Same with a diode. A positive voltage on the arrow will cause a current to exist. Any ammeter will show that. If it is a junction diode, the holes are going to flow in the direction of the arrow, and the electrons are going to flow in the opposite direction.
That is about it. Just follow the above procedure methodically. Ask if you have any questions.
Ratch