Sunday, April 20, 2014

7.5V to Input destroyed my arduino pro mini

I thought like "just excessive 2.5V or so would never break the device," but it destroyed the device. Or maybe occasional short circuit would break some pins because I didn't cover the exposed copper area. I should have considered the voltage drop at the LED, or I would draw the line to the input pin from the kathode side of the LED.

I replaced the resistor so the Input gets 5.0V at maximum, and I painted the copper plane with green resist.  Now it's working fine.