Adventures in Low Power Land. Skill Level: Intermediate by Nate | August 09, 2011 | 32 comments I was working on a project called BigTime where low power operation was a necessity.
Here's a tutorial to show you some of the tricks I found to get the power consumption down to about 1uA (that's micro, not milli = 0.000001A). I'm pretty sure rubbing your fingers together produces more heat energy than 1 microamp. My overall goal was to get an ATmega328 to go to the deepest sleep possible, waking up only with an external INT button interrupt or with a 32.768kHz TMR2 overflow interrupt (for an RTC). Arduino Low Power - How To Run ATmega328P For a Year On Coin Cell Battery.
An Arduino Uno runs less than one day on a 9 V battery because it uses about 45 mA current.
Using an Arduino Pro Mini, with a simple modification, the power consumption goes down to 54 μA (0.054 mA) with the 3.3 V version or 23 μA (0.023 mA) with the 5 V version, in power-down sleep. That is 4 years on a 9 V battery with 1,200 mAh capacity or 2,000 times more efficient than the Arduino Uno. After removing the voltage regulator, the power consumption is only 4.5 μA for the 3.3 V version and 5.8 μA for the 5 V version, in power-down sleep.
Adventures in Low Power Land. Tout ce que vous pourriez vous demander sur la consommation d'une puce ATmega328p (puce d'Arduino) Gammon Forum : Electronics : Microprocessors : Power saving techniques for microprocessors. Summary In this thread I show various power-saving techniques for the Atmega328P processor.
They include sleep modes, use of power-reduction registers, and other techniques. Applying all of them can result in a current draw as low as approximately 100 nano-amps (100 nA), well below the self-discharge rate of most batteries. Proof from the datasheet for the Atmega328P (page 405 of my copy): That is 100 nA at at 25°C running at 3v.