Like the title says: If you cut the power on the Vin pin, how long does the arduino (uno or nano) keep running under normal circumstances? (assuming the 5v circuit does not feed external components). I always forget to implement a save-settings-upon-power down. And some projects could use such a f…

If you kill the power before the voltage regulator, do you have time time store things in EEPROM?

noiasca November 21, 2022, 8:56am 3

if you add a capacitor (1000µF) and a diode, and measure when you loose Vin you can reliable write your settings to EEPROM with that 1000µF.

edit: found an old post of mine with several values/diodes:

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