Can the Delyk Charge Pump be modified for 12V input?

[suncrush]

Looking at this:

http://pcb.delyk.com/utility-boards/17-charge-pump-pcb.html

I'd be interested in using a 12V input to run the heater circuit of a 12AU7, while using the charge pump to increase the plate voltage.

I assume changing the input voltage to 125% of design would increase output voltage similarly, so the 33 V pad should supply something around 41 V (exact value unimportant--just trying to squeeze out more clean headspace.)

I assume the key idea is not blowing up the caps.

Am I thinking about this the right way?

[Groovenut]

You should be able to increase the input voltage to 12v, but be aware of the max input voltage of IC1. Some DC-DC converters have a max input voltage of 9V, other 12V others 18V. Next step as you noted, is to make sure you caps can handle the voltage at the stage they are at.

[R.G.]

G.N. is correct. To add a bit of detail, the MAX1044 listed as an alternate IC can  >>NOT<< survive input voltages bigger than 10.000000V. The MAX1044 will not work with a 12V input.

The 7660S is specified to work at 12V, but has an absolute maximum of 13.0V, so your "12V" input must not wander higher than 13.0V.

The LT1054 is specified to work at 15V. It is the only one of the three chips that I would trust.

And as G.N. says, be sure your capacitor voltages are specified to work at the higher voltage you will get.

[suncrush]

The IC is the voltage inverter.  You only need it if you plan to use the -9V pad.  It can be omitted otherwise.

EDIT--I think. I may just email the man, the myth and legend himself, and see what he suggests.

[Groovenut]

The IC is also the oscillator that enable the voltage doubling/tripling.