Emitter-collector shorted on npn transistor

Can anyone please tell me what's wrong with my schematic? When powering the circuit collector-emitter path on all 3 transistors gets shorted even though there is no current on base.

You mixed up voltage polarity. The emitter of a npn transistor goes to the negative supply, According to the hard-to-interpret LED symbol you may have to reverse GND and Vcc on the left hand side of your circuit.

Those are rgb LEDs. I am having a problem with them lighting up when there is no current on the base. I quite didn't get where I have switched the polarity. Would you mind explaining it?

You have your transistors upside down. The arrow on the emitter (general rule) points toward negative.

Well you are way over your head. You need to experiment with some simpler circuits, at the same time do some homework. Some directed advice can be given here, but it's not a technical school.

Oh i didn't think that could be a problem since I tried it on a breadboard and switched emitter and collector and the led lighted up in both cases. I used an smd transistor though. That could be the problem. Thank you for helping me :slight_smile:

You would if you did even very basic study of how BJT transistors work. And, it has nothing to do with whether its SMT or not.

Well it obviously has something to do with it being smd when it was working on the breadboard :slight_smile:

What about all the other differences that you don't know about? Most transistor types are available in many different packages, sometimes even different pinouts. But they are the same transistor.

I think, if you don't understand the difference between a collector and an emitter, your tests can't reach very solid conclusions.

Actually, it seems that you don't know the difference between an anode and a cathode either, since you mixed those up twice as well.

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