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Can I build a transistor through two diodes?

I am studying transistor and, from what I understand, a transistor it is two diodos, right?

I am thinking using two diode, just like this (see image), to make the place the transistor (e.g. BC548).

Someone already experience this?

Edgar Oliveira
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    The essense of a BJT is that the base is **thin** and that is **one P or N region** sandwiched between two opposite regions. So No. A BJT has to PN junctions, that does not mean that it contains two **separate** diodes either. – Bimpelrekkie Dec 16 '16 at 15:49
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    A transistor has an NPN or PNP semiconducting stack all bonded together, with two diodes you'd either get NP-metal-NP or NP-metal-PN, neither of which is quite the same unfortunately. – Sam Dec 16 '16 at 21:34

2 Answers2

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You just can't. There's a transistor-model which is explained with two diodes and you can measure the two diodes in the transistor but you cannot make a transistor with two diodes.

The NPN transistor has two pn-junctions, same as your diodes, but in the transistor there's only N-P-N, in your diodes you have N-P-metal-breadboard-metal-P-N. When switching on the transistor, there are electrons going from emitter to the base. The base is very thin, so most of the electrons diffund directly to the collector. The assymetrical doping of collector and emitter and the very thin shared base differs the real transistor from your diodes.

Franz Forstmayr
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No. A transistor needs the electric field interaction between the substrate and the emitter/collector (or the source/drain) nodes.

Richard Crowley
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