cumesoftware,
"The voltage applied to the base emitter junction controls the collector current and the base current is a result of the additional hole injection (for an npn BJT) into the emitter as well as the recombination in the base-emitter depletion region and the quasi-neutral base region."
All this extra activity causing base current is inevitable, but not a part of what controls Ic. The base-emitter depletion region changes with the Vbe, and that is the real cause of Ic change. It just happens that Ib, like Ic, is also exponentially related to Vbe, so Ic is proportional to Ib, but not the cause of Ic.
Indeed. You are prudent to be skeptical.My sincere apologies, but my doubt was reasonable, you have to admit.
Will do. I did not even notice that I was automatically writing come instead of cume.However, I've noticed that you write "comesoftware". Please, address me as "cumesoftware" or "cume" next time, if you please.
Well, that is where we disagree. Remember what the professor said?That seems an "egg and chicken" issue here. Indeed, you can control the collector current by controlling the base voltage, because of the emitter diode characteristics. But you can't conclude that a BJT is a voltage controlled device. In order for a BJT to work, it needs to have current drawn form the base, and not a voltage present at the base (BJTs are not FETs). And the collector current is proportional to the base current. Thus, it is more accurate to say that a BJT is a current controlled device.
"The voltage applied to the base emitter junction controls the collector current and the base current is a result of the additional hole injection (for an npn BJT) into the emitter as well as the recombination in the base-emitter depletion region and the quasi-neutral base region."
All this extra activity causing base current is inevitable, but not a part of what controls Ic. The base-emitter depletion region changes with the Vbe, and that is the real cause of Ic change. It just happens that Ib, like Ic, is also exponentially related to Vbe, so Ic is proportional to Ib, but not the cause of Ic.
I did not think he did, and I replied as such. Yes, we were all primed to go.Dave had shown hard evidence on that. However, it seems that this thread is going personal. Partly my fault, I must say. But I've only lit the fuse.
Automatically.Do they have a permit?
Does he back up what he is saying? RatchAs my final note:
If BJTs had selenium cores and gold plated bolts, they could work as voltage controlled devices due to some spiritual turbulence. This idea was proposed by Ivo Shandor in the early 20's, I think.
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