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Trouble finding non-schottky SMD power diode

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MustardMan:
@Zoli
LOL. Yes, I did search digikey. In fact, that was where I got the first of those graphs I posted.

The error I made, and probably not stated very clearly, was I was under the impression that Vf for a silicon PN diode was 0.7 volts at 25C. After looking at dozens (maybe up around a hundred) of datasheets the only one I found that indicated a Vf of about 0.7 (at 10mA - a reasonable current) was that one from MCC. All the others I saw were about 0.6 volts. My (wrong) assumption was manufacturers had simply switched to schottky.

So yes, I was wrong, I had made some wrong assumptions, and I feel embarrassed about them.


But the question I now have is the one I stated above... the commonly accepted forward voltage drop of a silicon PN junction is 0.7 volts. So why are so many datasheets showing it lower? Is it?

@Circlotron
Agree. We were all (mostly) taught in school to have the driving variable on the x-axis and the driven variable on the y.
So, it may not be what is expected, but at least all manufacturers seem to be consistent.

Cheers all, MM.

Dabbot:

--- Quote from: MustardMan on August 23, 2020, 06:52:46 am ---But the question I now have is the one I stated above... the commonly accepted forward voltage drop of a silicon PN junction is 0.7 volts. So why are so many datasheets showing it lower? Is it?

--- End quote ---

It's simply a reasonable estimate. The actual value will be around this estimate, depending on device type, temperature and current.

TheUnnamedNewbie:

--- Quote from: Circlotron on August 23, 2020, 12:42:36 am ---Why do semiconductor manufacturers draw diode graphs like that? Usually you want to know the unknown forward voltage drop at a known current, so the current (the independent variable) should be across the bottom and the voltage drop (the dependent variable) should be up the side! I can’t think of a case where you would apply a certain voltage to a diode and need to know what the resulting current is.

--- End quote ---

I have always thought of them being more logical this way. After all, when I learn and think of semiconductor devices, I usually do so with I-V curves, where you look at current as a function of voltage. So I just 'know' diodes as having that specific curve, and 'want' them to be shown in that way (as it is also the way that it is shown on our SMUs and so on).

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