A simple 12v inverter circuit please...

Thread Starter


Joined Apr 27, 2011

I have an old digital clock for which I would like to create a power supply. It requires 12v AC at exactly 50Hz, which it uses for timing purposes.

I could just buy an AC to AC 12v mains adapter and plug it into the mains. However it would be nice to also power it from a 12 volt battery.

Please can anyone suggest a simple 12v DC to AC inverter circuit to give 50Hz from my battery pack?

Will maintaining exactly 50Hz from a battery source be difficult, thus making the clock inaccurate for timing?

Many Thanks :)


Joined Apr 20, 2004
Do you need an inverter to power the circuitry as well, or can you give it 12 volts from something like a wall transformer, and simply make a 50 Hz oscillator to supply the timing?


Joined Mar 24, 2008
Welcome to AAC!

The only problem I see with your idea (and it is not a showstopper) is you need an accurate clock. A very accurate clock. Most simple inverter circuits use RC oscillators, which is pretty far from being accurate.

The first thing you would need to come up with is a decent 50Hz time base. Something like a 100Khz crystal oscillator divided down to 50Hz. From there a simple power amp (digital) and a transformer would power the clock nicely.

AC/DC Inverters