I made two LED controllers using an ESP. On the PCB I'm using three 2N2222 transistors + resistor (1k Ohm) at the base to control the 12V circuit powering the LED strips by applying 3.3V from the ESP.
Schematic (Q1, Q2 and Q3 have been replaced by the transistors):
Now I've got a problem: On one of the two controllers the Q2 transistor keeps blowing (Q2 is RED, not GREEN, as I accidentally mixed something up). It seems to be the LED strip, because I put it in place of the other controller and now it's working fine.
Could the problem be that the LED strip is too long? Or is there something faulty and I need to replace the whole strip? If more info is needed, I'll gladly provide it.
Edit: I still have the original controller, which uses an IR remote. If there's anything I need to measure while the strip is on, I can do that too.
The resistor soldered to the base of the transistor works, I just checked that. The red LEDs start flickering, and at some point the transistor blows