Trying to make battery powered stepper motor clock


I am a complete noob to arduino and I am trying to make a battery powered clock using a stepper motor and arduino. Is it possible to do this and meet these requirements?


An Arduino alone would not run a year on AA batts, also stepper motors (even a small one like yours) are not suited to battery operation, too much current demand.

IIRC the motor in watches is also called stepper. But it is very different kind of "motor" designed to operate with nearly no current (and with minimal strength). To run from 2 AAs for year (or more) you need 1) stepper designed for clock operation 2) board tweaked for minimal consumption or standalone chip 3) a decent time source - at least crystal

If you want just analog clock you maybe need no MCU. Just oscillator to drive the crystal and counter to drive the motor?

You'd need an ultra low power motor for that bettery life - the sort designed for the purpose as has been pointed out.

Typical current drain required for long battery life is a few tens of microamps. Typical current drain of normal small stepper motor: between 0.2 and 1A - 4 to 5 orders of magnitude too large...

thanks for the great info!

would it be possible to run ├čtepper/arduino from a wall socket?

Yes, with an AC to 5 volt DC (regulated) adapter, or "wall wart". You will also need a driver module if you didn't get one with the motor.

The main problem is that the resonator on an arduino is not accurate. You need an external RTC module to actually keep track of the time.

Any RTC will output an accurate one second square-wave pulse. What you would do is hook this to an interrupt and tell your arduino to go to sleep and wake on interrupt.

What kind of clock moves 12 times per hour? Why just one year? Why not say you need AA to run 10 years?