For instructions on how to install an Arduino library, check out this tutorial. All of the registers are well documented in the datasheet for the ATmega328p, but, if directly writing to registers makes you uncomfortable, there is a library available that you can download from the link below. Using software allows you to enable the circuits you need, when you need them, and, when you're done, you can disable them again.

If your project doesn't need to use the ADC, disabling it will cut down on the power draw drastically.īut what if you still need the ADC? Thankfully there are registers where you can disable some of these circuits with software. The analog to digital converter (ADC) does just as the name suggests, it take the analog voltage (which can be any value from 0V up to VCC) and converts it to a digital value that the microcontroller can use (0-1023 for 10-bit converters). If it does, the controller powers down until the voltage is increased above that threshold. The brown-out detection actively monitors the system voltage to ensure it doesn't drop below its threshold. Some of the other circuitry built into the ATmega328P include:Įach of these independent components need power to work, and, unless you manually disable them, they will continue to draw power. By offloading some of the work, the microcontroller is able to do multiple things at the same time. From there, the processor stops what it's doing and handles the interrupt by switching the pin's state. Instead, the Arduino uses one of the built in timers to count clock cycles and send an interrupt request to the processor. The Arduino's analogWrite() function, for example, doesn't have the processor create a PWM signal by counting the clock cycles itself. Inside the ATmega328P, lies a series of circuits that work together to offload work from the processor, and each of these draws some amount of power. So far we've talked about how to reduce the power of the Arduino, but we haven't talked about why it uses the power it does.

Arduino uno datasheet power