ac from +5 volts?

Thread Starter


Joined Jan 19, 2004
If I send a +5v square wave into the secondary of a 120v/5v transformer, will I get a/c on the primary? Would it be 120v, 60v, or a different RMS value?

Does frequency have a bearing on current capacity as well? Eg. 400hz vs 2kHz

I want to use a microcontroller to drive electroluminescent wire (neon wire).

Thanks for help.



Joined Apr 20, 2004

Don't think that approach would be entirely successful. The transformer will not be real happy with a square wave input, but the inductance will round things off a bit. The hard part is the frequency - a 60 Hz transformer won't do with a 400 Hz - or 2 kHz - input. The coils and core are a resonant structure, so off frequencies will not produce expected outputs.

Also, the step-up ratio is 24 to 1. If your neon tube requires 100 ma to light, you will also need to supply 24 times as much current to the secondary - 2.4 amps. Your source isn't likely to be able to handle the load.


Joined May 16, 2005
What frequency and voltage do these specific EL wires need? Stats for EL wires are all over the map.

And do they really need a sine wave?
coil front = crystal ear phone
coil back = led1 & led2 "One led is hooked diff from the other" imagine 2 leds hooked to one side of the coil.

Tap the earpeice with a pencil, led1 will light. as led one burns out, led 2 will light. this shows time in the coil.