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I used the LM337 negative regulator to regulate a +12V from a PC power supply.
And connected the GND to input and the +12 to ground of the circuit, and i got it work (i mean it's regulating the voltage) but the problem is it's get very hot even with heat sink connected to it. Is that normal because i didn't keep it on for a long time.
It used to regulate 12 volts to 3.2 volts.