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What is a transistor? Answered

Hey guys,

I am having problems understanding what is a transistor. When I do a search it shows me that its made of semi-conductor material and stuff, I don't want to know that. I want to know what is does as in a battery supplies power, resistor limits current etc. I would really like it if someone could give me a basic explanation of what is a transistor. Thanks in advance :).

-Prickly Potato

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KitemanBest Answer (author)2015-03-30

It's a switch with no moving parts.

Simply, a current is "trying" to flow between the collector and emitter terminals, and when a voltage is sent to the base terminal the switch "closes" and the current flows.

The current triggering the base is typically much smaller than the current being controlled.

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rickharris (author)Kiteman2015-03-30

Don't want to be picky but normal transistors are current driven rather than voltage activated.

for more detail read my instructable posted below.

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steveastrouk (author)rickharris2015-03-30

Slightly pickier...The BJT is current driven, the FET is voltage driven....

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Kiteman (author)rickharris2015-03-30

Pick away - it's what I get for posting tired.

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user

Can you describe what you mean by base terminal

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user

http://sm0vpo.altervista.org/begin/bc547.gif

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seandogue (author)2015-03-30

A standard bipolar junction transistor is not a switch, as some might have you believe. Instead it is far more accurately described as a current-controlled valve, since it can be used as a switch OR as an amplifier.

In a similar way, a FET (field effect transistor) can be more accurately described as a voltage-controlled valve, again, since it can be used as both a switch or an amplfier.

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seandogue (author)seandogue2015-03-30

Just goes to show you what a popularity contest this site has become. What a joke. Kiteman had it completely wrong.

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mpilchfamily (author)2015-03-30

Gotta read more then the first paragraph or 2 of an article if you want to learn about something. ;)

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