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How to wire NPN transistor

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FireAce

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Everyone uses NPN transistors, cant live without em. But how to hook them up. Most circuits I see seem to have the load between Positive and the collector. Others have the load between Emitter and ground. Is there a "better" way, and which do you prefer?

I have been successful with both.
 
There is no real difference, as far as I am concerned. They both work about the same. I personally prefer to put the load between the emitter and ground because it allows me to add more transistors (if necessary) much more easily. I can simply connect the emitter of the first transistor to the base of the second one, etc., whereas that's harder to do between the collector and positive. It all depends on what the load is and your personal preference.
 
Everyone uses NPN transistors, cant live without em. But how to hook them up. Most circuits I see seem to have the load between Positive and the collector. Others have the load between Emitter and ground. Is there a "better" way, and which do you prefer?

I have been successful with both.

A load in the collector is used normally to amplify the base signal voltage, a load in the emitter circuit will not give any voltage gain.
Google for transistor amplifiers.

https://en.wikibooks.org/wiki/Electronics/Amplifiers
 
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A load in the collector is used normally to amplify the base signal voltage, a load in the emitter circuit will not give any voltage gain.
Other differences are that a load in the collector (common-emitter circuit) gives a higher output impedance, a lower frequency response, and inverts the signal polarity, as compared to a load in the emitter (emitter-follower circuit), which has a lower output impedance, higher frequency response, and is non-inverting.

So it's really not so much a matter of preference as it is what you want the transistor amplifier to do.
 
Thanks fellows, makes perfect sense. I remember now, when hooking load such as a relay to Emitter and ground, the relay would only get the voltage I would send into the base. No gain or anything, totally disregarding collector voltage.
 
Other differences are that a load in the collector (common-emitter circuit) gives a higher output impedance, a lower frequency response, and inverts the signal polarity, as compared to a load in the emitter (emitter-follower circuit), which has a lower output impedance, higher frequency response, and is non-inverting.

So it's really not so much a matter of preference as it is what you want the transistor amplifier to do.

Yeah, sorry. I didn't even think about that...:eek:
Thanks everyone for clearing that up!
 
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