would anyone be interested in a charge pump daughter board for PNP/NPN projects?

[caress]

since there are so many threads about PNP/NPN projects working together, how many people would be interested in a tiny (probably 1" square or smaller) charge pump daughter board that they could incorporate into their builds?  i can design the PCB and have them professionally made (double sided board, through plated, silk screened) - they'd probably be between $2-5 after shipping in the US...  charge pump + some power supply filtering on one board?

also it would be based around the LT1054, which provides up to 100ma current and doesn't have any problems with HF noise.
i could add other options like an additional spot for a 5v regulator or something like that?  but it might be easier to just keep it simple...

pads for:
9V+ and ground IN
9V+, 9V-, ground OUT

[caress]

i did a quick layout.  i could add a reverse polarity protection diode as well if necessary... size is around .9" x .7" though i could get it smaller if i stood the resistor on end.  at this size it would probably come to only $2-3 a board after shipping.



BOM:
1 - LT1054
2 - 10uf capacitor
1 - 220uf capacitor
1 - .1uf capacitor
1 - 10pf capacitor
1 - 10ohm resistor

any interest?

[jkokura]

Great idea! I do it all the time though, did you know this already exists?

http://www.madbeanpedals.com/projects/RoadRage/docs/RoadRage_ver.3.pdf

http://www.muzique.com/schem/projects.htm (Voltage Doubler partway down... Also outputs +9V or -9V along with 18V)

Jacob

[Hides-His-Eyes]

never seen a 1054...

[caress]

ah i didn't know about madbean's layout.
i guess i was thinking about having something be pretty application specific to minimize size, etc.  the muzique board is twice as big and 4-5 times as expensive as the board i'm considering.  also, this board is specific to the LT1054 as i've added a capacitor to raise the frequency higher than the normal 25khz.  you don't have to use it, though... 

i would highly recommend the LT1054 over a MAX1044 any day - higher oscillator frequency, delivers 10x as much current and half the price.

well, if anyone's interested i can get them printed up.  if not, no worries!

[jkokura]

So is it possible to use the LT1054 with the Madbean board? Is it a cap addition or a cap change? As it is, you can get the boards for 2 bucks each from Madbean and they're tiny, so as you said before you would charge 2-5 bucks, so the price is comparable.

I guess what I'm suggesting is that rather than put effort, time and money into a product that's cheaply available already, maybe you could show us how to use the chip you're recommending (which I like the sound of) with the pre-existing product that I usually use a TC1044 with (which is a lot cheaper than the MAX1044 and has better specs also).

Jacob

[caress]

LT1054 is a pin-for-pin drop in for a MAX1044 or comparable chip, so you can use it with madbean's board.
the cap addition may not be totally necessary, as the oscillator already runs at 25khz, but if you want to raise it higher, add a small value cap (5-10pf) between pins 2 and 7.

the board won't really take me any effort or time to make since i've already done the layout... 
it's smaller than madbean's board and more application specific is all.