In "Bipolar Juction Transitors" -> "Introduction"

Discussion in 'Feedback and Suggestions' started by Dimitrios Kalemis, Sep 24, 2013.

  1. Dimitrios Kalemis

    Thread Starter New Member

    Sep 24, 2013
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    In "Bipolar Juction Transitors" -> "Introduction"
    http://www.allaboutcircuits.com/vol_3/chpt_4/1.html
    all arrows (that denote current flow) in the images point to the wrong direction.

    We may also view this another way: the PNP transistor should be NPN
    and the NPN transitor should be PNP, in the images that have arrows to depict current flow.
     
  2. MaxHeadRoom

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    Jul 18, 2013
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    Electron Flow.
    Versus
    Conventional flow.
    Just as the diode (check valve) symbol is backwards in Electron flow.
    I believe it was Ben Franklin's fault?
    Max.
     
    Last edited: Sep 24, 2013
  3. Wendy

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  4. Dimitrios Kalemis

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    Sep 24, 2013
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    Let me rephrase: The arrows in the two images depict conventional flow, but they are incorrect and someone should fix that.
     
  5. Georacer

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    I'm pretty sure that, in the images, the arrows display the electron flow. In contrast, the arrow at the emitters of the NPN and PNP transistors indicates the conventional flow.
     
  6. Wendy

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    Having double checked I have to agree with Geo.
     
  7. Dimitrios Kalemis

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    Sep 24, 2013
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    You are both correct: "in the images, the arrows display the electron flow. In contrast, the arrow at the emitters of the NPN and PNP transistors indicates the conventional flow."

    But the arrows in the images should display the conventional flow, because the standard is that and the ebook adheres to this standard. Everywhere else, the ebook uses the conventional flow. Only in these two images does the ebook use the electron flow.

    For the ebook to be consistent, the arrows in these two images should use the conventional flow. This is what I am trying to explain.

    I think that you think I do not know the difference between conventional flow and electron flow, and PNP and NPN transistors and emitter arrows. I know all this stuff. This is why I am trying to help.
     
  8. Georacer

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    To my knowledge, the book mostly uses the electron flow direction to indicate current direction.

    Notice the current flow direction in the very beginning of the book, here: http://www.allaboutcircuits.com/vol_1/chpt_1/4.html
    Three quarters of the page down, the first figure with a battery in a circuit. It uses the electron flow.
     
  9. WBahn

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    Mar 31, 2012
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    The ebook claims to consistently use electron flow, but while that is the stated intent it is pretty much impossible to do so when you have multiple people contributing to it, many of whom are naturally going to thing in terms of the flow of charge and not of charge carriers.

    Personally, I think using electron (charge carrier) flow is not the best choice, but the people that own the site control the ebook and that is their right. It is one of the main reasons that I don't attempt to contribute to the ebook because I think it causes needless confusion by using carrier flow and not charge flow, if for no other reason than that no one that tries to use carrier flow (i.e., electron flow) does so consistently since they treat carriers as defacto positive charges in most places without even realizing it, yet don't adjust anything else for the fact that they are doing so.
     
  10. Wendy

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    You obviously did not read post #3. Early in the book it is stated that they will use electron flow theory, and this is the books standard. You may have misspoke yourself, but you did state it was showing conventional flow, it is not.

    If you find examples of conventional flow that are not stated as such, this would be an error. Personally I don't know of any.

    I also disagree with conventional flow, having seen too many processes that depend on electron flow for a valid explination, such as tubes and sputtering machines (which use plasma flow to carry material from the source to the target). With semiconductors it doesn't matter much, but there is more to electronics than semiconductors.

    Just my 2¢.
     
  11. WBahn

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    Conventional flow is about the flow of charge, not charge carriers. It is completely agnostic regarding the nature of the charge carriers and is completely internally consistent with either positive or negative charge carriers.

    But people that use "electron current" seldom make the distinction and so they treat electrons as charge carriers that are negatively charged one instant and as the charge that is flowing the next instant. As a result, they end up with a mishmash of inconsistent results that have to be disentangled piecemeal.
     
  12. Dimitrios Kalemis

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    Sep 24, 2013
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    Thank you very much for your explanations and your patience with me. I am sorry for wasting everyone's time and I truly apologize. I now understand. I thought that the ebook used conventional flow, because this is what everyone else is using.

    I am trying to find an image with conventional flow in the ebook but I am unable to. I cannot understand why I thought that this ebook was adhering to conventional flow. Never mind. My mind played a trick on me.

    But, in my defense, if the ebook used conventional flow, it would be better; it would be easier for people to read. Almost everyone uses conventional flow and they ask the readers to "reverse" the flow (the arrows) in their thoughts when they have to think about electrons flowing. In everyone else's written work, images and diagrams depict the conventional flow. This difference with everyone else's written work is what confused me.

    Again, I am grateful for your clarifications.
     
    Last edited: Oct 4, 2013
  13. Georacer

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    I know that in Greece (assuming that you live there) everyone teaches the conventional flow, but curricula around the world aren't unified nor consistent.

    I suspect that the conventional flow users represent a greater percentage, but I believe there is a great portion using the electron flow as well, especially in the older ages.
     
  14. Wendy

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    Again, it does not explain tubes (diodes or amplifiers) or other devices where the direction of carrier flow is important. Rather than trying to explain the exceptions, I feel it is better to learn the physics of electricity. I did not make the decision about the book, but I support it completely. Separating physics and electronic convention to something different has always struck me as off. Electronics is a subset of physics.

    I have no trouble at all keeping the direction of flow straight, never did.

    Neither of us is going to convince the other though, so I would suggest let it be.
     
  15. Dimitrios Kalemis

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    Sep 24, 2013
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    Yes, I live in Greece and everyone here uses and teaches the conventional flow. But I thought that in the UK and USA this also holds true.

    Anyway, it is the ebook's author's right to use whatever "convention" he wishes.
     
  16. WBahn

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    The use of conventional current in the U.S. is pretty much universal in engineering education. It is nearly universal in physics education as well. You primarily see it in technician-level education just because it long ago became entrenched and much of the focus at that level is applying formulas and following pro-forma procedures and the inconsistencies can be dealt with by internalizing a bunch of adjustments and compensations that are eventually made without even thinking about it whereas engineering and physics education emphasizes a more system-level approach in which internal consistency in the math is critical.
     
  17. MrChips

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    Oct 2, 2009
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    At the university level we teach physics, electricity and electronics using charge flow from positive to negative potential.
     
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