Ultra-simple, low-power 3V->1000V converter

you may be able to do some thing with an old tv or monitor line output flyback transformer?

daceo

Hi Daniel,

I took for a similar project a simple oneway camera with a flash and use this one for such purposes. The final voltage in the capacitor is around 350 V but easy tuneable, it works from a simple AA cell with a batteryclip and includes a simple discharge unit ;-)

Very easy to built, very cheap (go to the next photoshop and ask for thes empty cameras or buy anew one, you may need a bill ;-)

Viel zu kompliziert Daniel ;-)

Marte

Sounds similar to a camera flash circuit. A visit to might give some ideas.

Your proposed push-pull aspect rules out many simple single-IC solutions, yet would be required for a 2x output-doubler scheme. If you give up on both of those, a one-step flyback circuit can be used. Thirteen years ago I made a little HV supply using an LTC LT1172 and a small stepup transformer wound on an RM8 core with an A160 gap. It had to provide about 900mW to the load, which was a fast high-voltage opamp.* Other slower low-voltage ICs would be better suited for your lower-power requirement.

BTW, the camera flash-bulb crowd has nice low-power circuits. There're web sites describing converting a disposable camera's HV generator for general-purpose use.

• The overall circuit was to synchronize a light-phase shifter to the middle of the shutter-opening time of a video camera in a specialized motion-sensing microscope. It showed a blank field (from phase cancellation), except for any movement that occurred during the shutter's open time in each video field. The shutter could be open for 100us (1/10,000 shutter speed), and we'd catch and highlight any motion during that time. To change the phase of the light at mid-shutter, I used an LM1881 video sync chip to grab each video line's back-porch pulse, and used complex cPLD circuit to calculate the right lines to generate shutter-open and mid-shutter signals. An additional voltage-programmed delay circuit allowed fine tuning to the exact shutter midpoint. I programmed the cPLD to work for all of the Sony camera's shutter times, from 100us to 8 and 16.7ms (60 per sec). The phase-shift pulse was tuned in amplitude to drive an optical modulator crystal via the HV opamp. They had the microscope optics ready before I got the electronics done, and a cry of "waiting for the RIS-177" became the focus of several lectures during the Institute's annual review.

Oh I don't care about the circuit topology. This is just the first thing that crossed my mind.

Those are good points to start. I've got some RM's kicking around somewhere. For this application an RM 6 would probably big enough.

Time to start up LTSpice. This ought to be a fun project.

Thanks,

--Daniel

I've thought about that, too. I'll have to check no-load power consumption.

--Daniel

Somebody makes a fairly cheap handheld DVM/hipot tester that does all this already. I think I've seen it in Mouser or Digikey or somewhere like that. I'll look.

John

Hi Daniel,

Do you really think, your homebrew design will top a ready to use design?

Marte

Id use a mc33063 in flyback mode, this gives you 40v swing, a 4:1 transformer will be very easy to make, giving you 200v swing, too high ratio means problems with leakage inductance and capacitance, a 5 * multiplier is easy to make with 200v diodes, wich will give you 1000v. ofc you might want to make it a bit more than 1000v to allow for losses etc. the chip will regulate it. ive done similar thing several times and it works quite well, with very small footprint.

Colin =^.^=

You are in Germany? Buy a kit from Kemo like the ion kit which comes with a nice pi wound transformer.

Charles Wenzel has a number of designs close to what you seek, nicely laid out here:

Best, James Arthur

There's a low-power 3-to-500 volt converter here, toward the bottom of this page:

Cheers, James Arthur

On a sunny day (2 Mar 2007 14:54:39 -0800) it happened "James Arthur" wrote in :

More volts on batteries here:

Go buy one of those $10 bug-zapper tennis-racket style flyswats, and rip out the electronics. and maybe change the quadrupler to a doubler, or a singler :)

Cheers Terry