Early

Hi,

I read about early voltage, I did not understand it correctly (just found it is between 50 to 100V and has something to do with base depletion width width and W region). Can somebody explain it to me plz? Do I need to consider it when Designing a circuit? or it is useless?

Thanks

Early voltage, is that like a Baghdad battery?

Oh, well that is not at all what I was thinking, thanks Sceadwian...

See . . . the internet is better than any book or encyclopedia you can find on any shelf.
It’s a pity schools haven’t woken up to it. Kids are still lugging 10kgm of books to school each day to use 15 pages of material.

colin55 said:

See . . . the internet is better than any book or encyclopedia you can find on any shelf.
It’s a pity schools haven’t woken up to it. Kids are still lugging 10kgm of books to school each day to use 15 pages of material.

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In the US, unfortunately, that is all the exercise many of 'em get.
I agree, the internet is truly one of the modern wonders of technology. (Even though it is technically speaking close to 40 years old (the technology) and widespread public access has been around for 20 years.) Wow, to think and entire ADULT generation is coming of age having not known the world without it!

But I will take the warmth and comfort of a good book (I'm a tech, history, and science reader) over an LCD monitor anyday.

As for the Early Voltage thing.

Electronman, I'm certain that Early voltage effect is a fascinating subject, a nuance of electronics that is worth noting. But to be honest, this is the first time I've ever heard of it. Some of these less known phenomenon (generally) are not worth mentioning in practical electronics application. Their effects are only seen at extreme frequencies or highly specialized applications.

I take it from your posts that you are either a student or a very inquisitive hobbyist just starting to learn. You seem to grasp some of the complex concepts, and yet ask many questions about fundamental theory too. This is good, I applaud your tenacity. I would recommend, however, that you shouldn't bog yourself down or focus too much on concepts that aren't fundamental, universal, or broad in scope, or that don't have immediate and noteworthy consequences in circuit analysis or design. In other words, don't hang on every trivial word you read, you'll miss the important stuff.

ke5frf said:

As for the Early Voltage thing.

Electronman, I'm certain that Early voltage effect is a fascinating subject, a nuance of electronics that is worth noting. But to be honest, this is the first time I've ever heard of it. Some of these less known phenomenon (generally) are not worth mentioning in practical electronics application. Their effects are only seen at extreme frequencies or highly specialized applications.

I take it from your posts that you are either a student or a very inquisitive hobbyist just starting to learn. You seem to grasp some of the complex concepts, and yet ask many questions about fundamental theory too. This is good, I applaud your tenacity. I would recommend, however, that you shouldn't bog yourself down or focus too much on concepts that aren't fundamental, universal, or broad in scope, or that don't have immediate and noteworthy consequences in circuit analysis or design. In other words, don't hang on every trivial word you read, you'll miss the important stuff.

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Ke5frf, I agree that the Early effect is sort of a second-order effect. It primarily manifests itself as collector dynamic impedance, and beta change as a function of Vce, which can be important in some amplifier configurations, and in current source/sink designs. A good circuit designer will be aware of it.
There was a thread about 2 years ago that dealt with the Early effect. In it, I posted a spoof graph illustrating the Late effect (see attachment). Definitely engineering humor, possibly only funny to yours truly.

Roff said:

Ke5frf, I agree that the Early effect is sort of a second-order effect. It primarily manifests itself as collector dynamic impedance, and beta change as a function of Vce, which can be important in some amplifier configurations, and in current source/sink designs. A good circuit designer will be aware of it.
There was a thread about 2 years ago that dealt with the Early effect. In it, I posted a spoof graph illustrating the Late effect (see attachment). Definitely engineering humor, possibly only funny to yours truly.

Click to expand...

Actually, it was quite witty. Thanks for posting it and the link. Probably not Leno or Letterman material but we can't all be engineers, right? LOL

And I understand what you are saying, that it is worth being aware of for an amplifier designer. No doubt, if it is in an engineering student's texts it has some significance in some applications. In my way of thinking, however, I see a student here who is asking lots of questions almost daily. He obviously has great interest in learning, which is terrific. But I know. personally, when I'm studying I do my best to prioritize the material in my mind, taking note of things worth reading further in detail. Some things will be footnotes that I don't commit to memory....just familiarity with the terms is enough. I can always pull the books out later for reference.

I think this is the advice I wanted to pass to the OP. I get the feeling from his posts that he sort of spreads his energy out evenly when it comes to his studies, when perhaps attention to detail should be paid to the "bigger things".

The late effect has negative resistance so it will make a good oscillator.
I also have a spoof of the Early effect:

audioguru said:

The late effect has negative resistance so it will make a good oscillator.
I also have a spoof of the Early effect:

Click to expand...

You posted the VI curves of a geranium transistor. I happen to have a rare sample of one. It still works, and probably will as long as I remember to keep it watered.
Attached is a picture, along with the VI curves you posted.

The "geranium" spelling error was part of the spoof.
I also spelled "silicon" wrong but I corrected it.

audioguru said:

The "geranium" spelling error was part of the spoof.

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I figured that was the case. I just wanted to add to it.

You can add the silicone transistor (from Silicone Valley) to the mix.

crutschow said:

You can add the silicone transistor (from Silicone Valley) to the mix.

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Ain't that what they make them electronic breast implants out of?

This is a classic example of a thread drifting off topic, and it was all my fault.
BTW, I created that Late effect plot with an LTspice simulation.

Do the phoney breasts light up in the dark??

Edit:
I have never been near phoney silicon breasts. Do they rectify?