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How does a transistor work?? Answered

My understanding of a transistor is that the electrical current applied to of the pins alters the resistance of the other two pins, allowing electricity to flow or stopping the flow. Is that right?


"transistor man"

heh, you're a fan of Horowitz & Hill's the Art of Electronics, aye? I loved that book back in college and still ocassionally refer to it 20 some years later.

New edition due real soon now, according to Win Hill last time I asked him


Cool, you actually know him?

I have to say, they're my heroes. And I have VERY few heroes. Their book is probably one of the best teaching tools I've ever read. I remember some of the books we used early on in college being really dull and opaque, if you know what I mean. They handled it with a perfect combination of technical info, "common speak", and a tad of humor (like transistor man). At least perfect for me. I'd recommend that book to anyone who wants to get a good functional understanding of electronics.

We're vaguely acquainted. He helped me with an atto-farad sensitive detector I was building some time back.

Its just THE best electronics book ever written, its a shame its so out of date.

That's a great little cartoon :-) And certainly good enough for the level of expertise of both this person and your previous one.

Very very basic version. NPN type (one of the most common) transistors, if you put a current to the base terminal, a larger, proportionate current flow through the collector to the emitter. PNP (another most common) (I think, correct me if I am wrong), if you put current on the base terminal, the amount of current gets less the more current you put on the base (Inversely proportional to the base current). So if you put current on the base of a PNP type transistor, less current flows between the collector and emitter. You can get a whole lot more complicated than this with ratings and holes and semiconductor theory. I wont go there mostly because I dont understand a thing about it yet :)

If it's NPN, current at the base allows current to flow through the other pins (proportional to the voltage/current at base), PNP is the opposite.

No, that isn't correct. http://en.wikipedia.org/wiki/Transistor

Do you mean "how does it work" or "how does it behave"? Those are somewhat different questions.