300V power supply.

It would be fun to make a big CW, like a megavolt or something. A string of cheap PC boards could do that.

I'm not sure what you mean by a string of PC boards. I've got this guys book, where he makes a 250 kV C-W.

I think you need to start worrying about x-rays at those voltages.

Oh, the UCSB fel runs off a huge Van de Graff. (I guess it's real name is a pelletron.)

George H.

Oh that saves me some time! Thanks. GH

Er, no it isn't. It *really* isn't.

That LTC chip is not very expensive, and the simulation seems to work accurately. Unless you are going to make many thousand units, the chip is worth it.

from

/AN118fb.pdf

Maybe you missed the part about high reliability, ruggedization, burn-in an d cycling test. These are better than militarized. And they're going to cos t.

"Pico Electronics, Inc. is the industry leader for manufacturing high relia bility miniature and ultra-miniature passive magnetic components. From the depths of the oceans, to the surface of Mars, Pico?s transformers a nd inductors are used in the most rugged applications. Many Pico Transforme rs and Inductors have passed 300 thermal cycles and have been exposed to a variety of temperature extremes. Our products have been engineered, and des igned into, applications throughout the Aerospace, Defense, Space, and Comm ercial Industries. Where a design demands reliability, when size and weight constraints are a factor, Pico Electronics? products are the solut ion."

With air insulation, you'd find the limits at half a megavolt, if your room had a 12ft ceiling...

When I say 'your' room, I don't intend that you should be in it when the power is on.

The usual reason for HV transformers (insulation and winding intended for the purpose) is to drive cold cathode fluorescent backlights (so, it's a source that's drying up).

This datasheet says it all:

x-rays start a good order of magnitude below that

NT

Make a little PC board like his, 50 KV or so. Then string a bunch in series. Maybe battery power each one... a long pure CW string gets messy because of all the capacitors in series.

I want to buy a lot of doorknob capacitors, charge them one at a time to 30 KV, and poke them into a plastic pipe, in series.

Make sure the pipe is full of transformer oil. ;)

Cheers

Phil Hobbs

Erwin Otto Marx used to do something like that.

Jeroen Belleman

Marxist.

Shocking.

Tim

If efficiency and board area are not an issue and you are pushed for design time then using mains power transformers "backwards" is an easy option. SMPS flyback types or even plain ol' laminated 50/60Hz. Since your output current need is low I think a voltage doubler rectifier could be useful. Sometimes a low switching frequency is easier to cope with from a noise/EMI p.o.v.

piglet

That was Karl.

Yes.

Jeroen Belleman

I invented one topology that Phil called the Groucho Marx Generator.

Je suis Marxiste, tendance Groucho ...

from the 1968 student unrest in Paris.

Erwin Otto Marx doesn't seem to have member of Karl Marx's family (one of K arl Marx cousins set up Philips Electrical in the Netherlands, though it wa s the founder's sons who were the famous Philips brothers, so there is an e lectrical connection there) or related to any of the Marx brothers.

You'll have to settle for being electrically rather than politically shocke d.

No, that was Otto. The pun is in making the temporary redefinition. And now I've killed it. I hope you're happy. :^)

Tim

I thought Marxist Generators were colleges and universities.