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  1. R

    Diodes, silicon, structures

    OK, got it. It is going to take some time to assimilate this material. I will get back when I finish. Edit: I looked at the link andI would advise you to get another reference to study. The linked material does not systematically build the basic knowledge needed, and refers to terms and...
  2. R

    Diodes, silicon, structures

    I could not download the contents of the above link without going through some silly verification process, which I refuse to do. Ratch
  3. R

    Diodes, silicon, structures

    I don't think any of us in this forum know enough about silicon applications at the quantum level to be of much help to you. Your questions appear to be at the post graduate level in material science. Sorry, but we are mostly skilled in electronic and electrical applications. Ratch
  4. R

    Can someone explain me how a BJT works?

    Bill Beaty's site called Amazing Science, that you reference above is basically correct. One of his virtues is that he does not use the scientific slang lingo of "current flow". Instead, he uses the correct description of "charge flow". One thing does bother me about that site, however, is that...
  5. R

    Can someone explain me how a BJT works?

    I would like to correct some of the statements above. I base my understanding of how a BJT works on the physics of the semiconductor, not on models. Models tell you what a device does, but not how it works. I consider evolution a pseudoscience. The idea that high complexity can come from...
  6. R

    Can someone explain me how a BJT works?

    Abstractions and models are fine for design work, but the subject of this thread is "How a BJT works". Only one of us can be correct about this subject. Both of us are correct in not accepting each other's position, if we believe our own position is correct. I hope to prove my position is...
  7. R

    Can someone explain me how a BJT works?

    There are plenty of books and literature on how diodes and transistors work. Go as deep as you want. I also gave you a thumbnail explanation in post #13 of this thread. Did you read it? Any questions? No one can tell you how to study this subject. No one source has all knowledge on this...
  8. R

    Can someone explain me how a BJT works?

    You picked the wrong subject to aver is true, because it can be proven definitively that a single BJT is a transconductace amplifier. A BJT is not a current amplifier which you and the video presenter seem to think is the case. This means that the Vbe voltage controls the collector current...
  9. R

    Can someone explain me how a BJT works?

    I am not a teacher. Therefore, I cannot advise you on what method you might find better than another. Besides, I don't have those books. Ratch
  10. R

    Can someone explain me how a BJT works?

    OK lets talk about a BJT. We start with a junction diode. The N and P slabs are physically connected together. Immediately the negative electrons from the N slab will diffuse into the P slab because they are attracted by the positive holes and will be neutralized. Simultaneously, the holes...
  11. R

    Can someone explain me how a BJT works?

    Those terms are readily defined in any textbook about semiconductor. OK, a BJT if a bipolar device, in that it uses both holes and electrons as its current carriers. A FET is a unipolar device that uses either holes or electrons, but not both. A BJT controls its collector current by varying...
  12. R

    Can someone explain me how a BJT works?

    Not so great video. The presenter appears to believe that Ib controls Ic, which it does not. Vbe controls Ic. Without some emitter resistor, that circuit will send double the current through the fan if the beta of the BJT happens to be twice what he assumed. I wish I could talk to that...
  13. R

    Can someone explain me how a BJT works?

    What is it that you don't fully underestand? Ratch
  14. R

    Common collector configuraton

    No, it won't. Last time I gave an example where the current in the emitter circuit was 10 ma. That current was "locked" into its value because of the 5 volts on the base terminal, the Vbe, the current limiting resistor, the the voltage across the LED. If you used a transistor with a...
  15. R

    Common collector configuraton

    Why does a Vbe tempco of -2mv/C° justify classifying a BJT as a "current amplifier"? As long as it is operated in its active region, a BJT is a transconductance amplifier. And the point is? Are we talking about operation in the active region? Ratch
  16. R

    Common collector configuraton

    You have good reason to doubt your understanding of BJTs. Your perception of how a BJT works, as described below, is wrong. By the way, the word you want to use is patience, not patients. A transistor is a transconductance device (voltage controls current). The current present in the base...
  17. R

    Common collector configuraton

    Are you referring to whether the transistor is a PNP or a NPN? I was thinking of a PNP. Thanks for the polarity picture. Better yet, I should have said "difference". Ratch
  18. R

    Common collector configuraton

    You are describing a current amplifier above. You are confusing input impedance with amplification. An emitter-follower has a high impedance because the input base voltage source needs to supply or sink a much small current than it would if it were connected directly to the emitter resistor...
  19. R

    Signal is periodic or aperiodic

    Don't you know that all trig functions are periodic? Plot it out and see. Ratch
  20. R

    Resistive voltage dividers and flowing currents.

    Where is the second of three resistors? Where is "R2" marked on the schematic? What is the resistance of the two 1 ohm resistors in parallel? Ratch
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