How can I use a MOSFET and voltage multiplier to generate a high voltage spark?

[Curl]

I need to make a large voltage, possibly to make a spark across a 0.05mm gap or at least to make a very large voltage across a resistor. I need this to be triggered digitally by a micro-controller.

I was thinking of setting up an inductor and a power MOSFET, but I don't know if this will work. Can anyone help sketch a circuit that would accomplish what I described?

Thanks!

 

[berkeman]

I need to make a large voltage, possibly to make a spark across a 0.05mm gap or at least to make a very large voltage across a resistor. I need this to be triggered digitally by a micro-controller.

I was thinking of setting up an inductor and a power MOSFET, but I don't know if this will work. Can anyone help sketch a circuit that would accomplish what I described?

Thanks!

From our PMs, it sounds like you just need a spark plug circuit. Can you just use a spark plug ignition circuit off of a lawn mower or similar?

 

[NewtonianAlch]

My thoughts exactly, a simple ignition circuit is all you will need. In regards to triggering it by a micro-controller will definitely require a bit of modification.

 

[NewtonianAlch]

Not too sure what you're exactly trying to do so it's hard to say.

http://img502.imageshack.us/img502/5589/10322599.jpg

There's an example.

Needless to say, if you're going to be trying to get sparks, that's kV running from the coil to the plug, so use insulated wiring, preferably BOSCH or something similar from auto shops.

As to triggering it from a micro-controller, how about triggering the battery with a simple switch breaking contact with the rest of the circuit when you don't want it turned on?*Image taken from Fundamentals of Electric Circuits (4th Ed) - Alexander, Sadiku p.353

 

[alphysicist]

I would suggest using a voltage multiplier circuit to achieve your goal of creating a large voltage. This circuit consists of multiple stages of diodes and capacitors that can increase the voltage output. You can control the triggering of the voltage multiplier using a MOSFET, which can be controlled by the micro-controller. This setup will allow you to generate a high voltage pulse that can create a spark across a small gap or produce a large voltage across a resistor. I would recommend consulting with a professional or experienced engineer to help you sketch out a specific circuit that fits your needs and ensure safety precautions are taken.