Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: Admin on April 23, 2007, 09:15:11 AM

Title: I need 200V
Post by: Admin on April 23, 2007, 09:15:11 AM
I have this project where I need to generate at least 200V and probably more around 900V, but I only need about 1mA maximum in current (probably less).

The other requirement is that at least one dimension on the device needs to be less than 1cm.

So the question is, what can I do (or buy) to obtain this voltage?

My thought was possibly some kind of charge pump, or multiple charge pumps in series.

(yea, yet another strange question that Im not allowed to elaborate on)
Title: Re: I need 200V
Post by: hazzer123 on April 23, 2007, 09:49:18 AM
Could you possibly modify a photo flash capacitor charger? They have voltages of 300V outputted using just a AA battery. They are pretty small aswell.

The 1cm dimension you mentioned, could that be the height of the components on the board? Or did you mean width and height of the board?

Title: Re: I need 200V
Post by: Admin on April 23, 2007, 10:13:56 AM
Quote
The 1cm dimension you mentioned, could that be the height of the components on the board? Or did you mean width and height of the board?
thats just one dimension, the other 2 can be any reasonable size
Title: Re: I need 200V
Post by: hazzer123 on April 23, 2007, 10:25:17 AM
Then these boards may be good for you :)
I think that if you needed higher current, that you would simply need to add a larger voltage to the supply as well. Im not sure though.
Title: Re: I need 200V
Post by: Admin on April 23, 2007, 11:32:56 AM
oh and forgot to mention this so i will just in case . . .

The entire robot (including battery) needs to be smaller than 1cm in one of its dimensions . . . crazy, I know, but I dont make up the requirements for these kinds of things . . .
Title: Re: I need 200V
Post by: hazzer123 on April 23, 2007, 11:56:36 AM
Ive just measured an old board that i had from a disposable camera and the tallest component is the transformer, and it is just about 1cm.

The 1.5V could come from an AAA alkaline battery which are 10.5mm in diameter. (is that too big?) That should be plenty of current i think...

(edit - there are AAAA batteries with a diameter of 8.6mm. Hmmm never seen them before.)
Title: Re: I need 200V
Post by: Admin on April 23, 2007, 12:01:47 PM
I was thinking of using one these batteries:

http://www.powerstream.com/ultra-light.htm

http://www.powerstream.com/thin-lithium-ion.htm
Title: Re: I need 200V
Post by: ed1380 on April 23, 2007, 02:19:27 PM
some transformers in serial, and a thin battery should do
transformers for camera's are pretty small
Title: Re: I need 200V
Post by: Admin on April 25, 2007, 08:29:00 AM
Looking in to it more I found that a CCFL (cold cathode fluorescent lamp) driver can generate between 200V to 1500V in a tiny package. They are commonly used to power the backlight of LCD panels, and can also be found in cameras. They tend to give out a PWM (on/off square wave) of about 1-50khz . . .

An example of a 1100V CCFL for 4mA image is attached as an example . . .

And a datasheet for cxa-k0505-vjl (from digikey at $25) with specs
https://www.tdk.co.jp/tefe02/ea441_cxak0505.pdf

Maxim has some CCFL drivers (http://search.maxim-ic.com/search?q=CCFL+driver&restrict=english_products&image.x=24&image.y=11&image=submit&ie=utf-8&site=Maxim&filter=0&output=xml_no_dtd&client=Maxim&image=submit&num=20&proxystylesheet=http%3A%2F%2Fwww.maxim-ic.com%2Fsearch%2Fsearch3.xcgi&oe=utf-8) too, but still looking around . . .
Title: Re: I need 200V
Post by: nanob0t on April 25, 2007, 09:23:38 AM
This website has plans available in order to produce your own voltage regulator.  I believe they have a variety of plans and it's possible to get something up to 2000 volts.  Although they do have stuff that produces 1,000,000 volts.  It's something like 2000 volts at 5mA.  Take a look, perhaps there's something useful:

http://www.amazing1.com/hv-dc-power-supplies.htm