I am attempting to make a battery powered alarm clock with an Arduino, and I would appreciate some help on the circuitry part. I am very inexperienced with electrical engineering.
I am using a voltage divider in parallel with the rest of my circuit so that I can feed it into a pin on an Arduino and read the battery life. I am using a two 100k resistors to lower my 4.5v power source to 2.25v (the maximum input voltage for a analog pin on an Arduino mini 3.3v is 3.3v). The three AAAs ran out of battery much quicker than expected, and I figured it might have something to do with the voltage divider. Is power constantly flowing through the voltage divider, even when I'm not reading any data from the pin? If so, does this reduce battery life?
Side question: I noticed the voltage divider was very inconsistent, is there a better way to lower the voltage going into the Arduino's analog pin?