How to make your Arduino Nano run on 3mA and sleep on only 0.3mA. In deep sleep mode you can make your arduino nano run on batteries for a long time.

We are going to test:
- which PIN is best for powering the Arduino
- remove the LED to save energy
- slow down the Arduino (clock prescaler)
- lower the voltage

AND

- Remove the voltage regulator and put the Arduino in sleep mode.
Note that the VIN pin do not work when the regulator is removed.

The same results can be expected from the Arduino Pro Mini as well.
Perfect when you want to run your low power arduino on a battery.


Code for sleep
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Code for sleep
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#include (insert Angled brackets)avr/sleep.h(insert Angled brackets)
void setup() {
CLKPR = 0x80;
CLKPR = 0x01;
}

void loop() {
set_sleep_mode(SLEEP_MODE_PWR_DOWN);
sleep_enable();
sleep_cpu();
}