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Topic: transistors? (Read 388 times) previous topic - next topic

michael040990

ok i know about npn pnp transistors but i want to salvage used ones from electronics to save a few bucks but they all seem to have different model numbers on them do they all still function the same?

outofoptions

Look up the numbers and see what they tell you.

JimboZA

Well all npn work the same in the sense that active they can switch a collector-side load on, and pnp's active can switch an emitter-side load off. (I think I got that the right way round  8) )

But they all differ in terms of gain and the voltage and current they can handle. A site like this is useful to get sight of the various datasheets.

This site might help, as might this.
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MarkT

Also they vary in their high-frequency performance and noise performance.   However for simple uses you really just
need to check the voltage, current, power and gain ratings are adequate.  Also for use as a switch the Vce(sat) rating
tells you how much voltage and power will be lost in it when switched on and carrying a certain current.
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mixania

They all work the same but just vary in quality and current handling.
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majenko

Be warned that what looks like a transistor may not be a transistor.  Besides NPN and PNP Bipolar Junction Transistors you also have FETs of various kinds, diodes, sensors, etc all in the same or similar housings.
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Grumpy_Mike

A lot of multimeters have a transistor testing socket on them. That will tell you what you have.
This project will tell you what you have and what pin out it is:-

http://www.thebox.myzen.co.uk/Hardware/Transistor_Tester.html

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