5V/10ohms = 0.5 Amp.
5V*5V/10ohms = 2.5 Watts.
Brilliant. Thanks for that. Now I see where your signature line comes from.
Plus, it’s much much worse if you’re not providing enough base drive to saturate transistor.
Worst case, 1.25 watts → transistor=poof!
There is enough drive. You keep talking about situations that, unless your a total zonk, should never occur. What if you attach the power to your Atmega328 backwards? What if you try to monitor a 12V signal directly? There are so many things you could do wrong, so I am not sure where you are coming from on this. That circuit is up a n running in my lab. It does not get hot, explode or glow if used the way it was intended. Just like so many things.
Read post #43.
Just because you said something from the OneD TenT file earlier does not make it any more realistic if you reference it again. You simply execute a digitalWrite(LOW) to the pin in question once you are done making pretty sounds. This is so obvious I’m embarrassed to have to spell it out.
Again, it you are a total zonk, then I could suggest some small alterations to the circuit that should allow it to deal with your shortcomings.
- Put a DC blocking capacitor on the input. This will require the addition of a cap and a resistor
- Use a 3W resistor on the collector
… and … change the base resistor to 500 ohms.
However, none of this is necessary as it works just fine as it is. BTW, any Canadian beer is better than Old Milwaukee!!
Even this guy know what I’m talking about.