Transistor VCE (collector-emitter voltage)

Hi,

Scale the experiment down a bit, or get some AA and a decent battery holder.

Tom.. :grinning: :+1: :coffee: :australia:

Thanks for the assist, I will try to experiment this soon, but maybe with a TO-220 or TO-92 package instead of a SOT and trimpot as RC and RB to experiment different values.

Yes, it would be impossible to experiment without one.

I think you are missing the point that if you put more current into a base than is required for saturation the transistor still saturates. You are dealing with a minimum requirement not the requirement.

+1.

I just been following along, but I happened to recently spend some quality time with my old favs 2N3904 and 2N3906, a handful of resistors and my meter.

Oh, and an LED. Illuminating. I was mostly looking into saturated switching, but took a look around, recommended.

a7

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So it seems. ... I give up! :laughing:

This is a common misunderstanding - normal transistor operation, for which hfe/Hfe applies, assumes the transistor is in the forward active mode, in which the base-collector junction is reverse-biased.

In saturation the base-collector junction becomes forward-biased and the device behaves completely differently as there's no voltage gradient to sweep charges injected by the emitter across the base into the collector. The charges flow by thermal diffusion only, and the current gain drops like a stone. Normally you only get about 10 to 20 fold current gain in saturation whether Hfe is 30 or 100 or 500.

We already clarified in post #24 that it was just a typo. And @Wawa is already fixed this typo.
The problem was not in 1:10, but that it would be better if the base current will be less than the collector current. :slight_smile:

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