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UV Cold Cathode Driver Circuit

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LiquidOrb24

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I recently found an old UV Cold Cathode lamp from my computer laying around an now I want to incorporate it into a circuit I'm building. I basically want the UV tube to turn on when the lights go out kind of like a night light and to run off of a 9 volt source.

The problem is that it needs 12 volts input to run and a power inverter to drive up the voltage to several hundred if not thousand volts.

My question is if there is any kind of schematic out there that is this power inverter that would be able to do this and what transformer in the power inverter would have to be rated at to achieve this?

Any help would be more than appreciated

Thanks
 
Yeah I hooked it up to 9 volts straight into the power inverter that came with it but only got a faint glow on one end, 12 volts did the same thing so I think one of the elements is damaged or something... I kind of want to strat from scratch and build my own but looking at the thing is really hard for me to reverse engineer because they have no parts specified on the transformer or capacitors. It looks like a relatively easy circuit but I would like to build one myself

I did reaseach on the net and found a few schematics but nothing that really helped me out.
 
No, that sounds about normal for a cold cathode tube when hooked up to a low voltage DC source to me. You can used a switched inductor to drive very high voltages. The easiest way I can think of would be to use a 555 to generate a 1khz 50% duty cycle signal and pulse the current through an inductor. When the 555 shuts off the inductor's voltage will spike, up to a couple hundred volts depending on the inductor, just bleed that pulse off with a diode to your lamp.
 
Out of curiosity, do you know how much current your cold cathode tube is drawing when just the tip of it is glowing? I'm not sure exactly of the schematic equivilants of a cold cathode tube but it may actually work as a rectifier so you don't even need a diode.
 
Looking through my junk box I found an old cold cathode driver I yanked out of a scanner and it's using a step up transformer with a simple two transistor oscilator to drive the primary, I'm not sure what the secondary rateing is as I can't find the transformer's markings online anywhere and I don't know how to measure it.
 
Why do you just do it properly and use a 12V battery?

10 AAA NMH cells will do the job, they're not that expensive and you can buy battery holders that will hold four of them, just connect them all in series.

You could mess around building a switching regulator to convert your 9V supply to 12V but it will reducy the efficiency and therefore the battery life and it isn't worth the trouble, it's much easier to select the correct battery for the job.
 
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