Hi there I have been trying to figure out why my transistors end up smoking when I get them to sink current from a 5VDC motor but I still don't understand it.
I am able to use the transistor to switch 3-5V to the motor, with the negative end of the motor sinked to ground, but if I try to sink current coming out of the motor using the same transistor it quickly starts to smoke. Use of resistors just makes the motor stop (not enough voltage). When both sourcing or sinking current the value is around 200mA, since its the same current passing through either way I can't understand why one way is fine but not the other. Can anyone give an explanation to this? The transistor I'm using is NPN 2N3904. I've tried it with multiple different transistors (all the same model number), and it gives the same result.
Please help!
I am able to use the transistor to switch 3-5V to the motor, with the negative end of the motor sinked to ground, but if I try to sink current coming out of the motor using the same transistor it quickly starts to smoke. Use of resistors just makes the motor stop (not enough voltage). When both sourcing or sinking current the value is around 200mA, since its the same current passing through either way I can't understand why one way is fine but not the other. Can anyone give an explanation to this? The transistor I'm using is NPN 2N3904. I've tried it with multiple different transistors (all the same model number), and it gives the same result.
Please help!
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