By mistake, I applied 12 volts to ATMega8 microcontroller. Did it get damaged?

Today, while doing a project on a breadboard, I accidentally connected 12 volts DC power supply to Ground pin of ATMega8 micro controller. Does this particular micro controller get damaged/malfunction because of this ?

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I accidentally connected 12 volts DC power supply to Ground pin of ATMega8 micro controller. Does this particular micro controller get damaged

  1. Could you check if it still works? If it was working before, but “after” not - it was damaged.
  2. If you didn’t check yet - it depends on the potentials on your Arduino and if or how the 12V DC was connected with BOTH pins. So: what about the GND of your 12V source - did you connect 12V plus/minus converted?

If GND wasn’t connected at all to your device - nothing should have happened.

Means: we need more information to answer your question.