Redesigning a boost converter circuit around an ATtiny85

The circuit in question is this: Uzzors2k Hobby Projects Site

It's well within my abilities to build it as-is (and indeed, I shall, once I've scrounged up some cores to wind the inductors), but I also have a few Tiny85's in the mail due any day now, and I was wondering if the circuit could be simplified in terms of component count by getting the 85 to do most of the work? It seems like I could make it pretty small with only one IC and for my application, the smaller the better!

The idea I had was to get the 85 to generate the switching waveform and also read the cap bank voltage through a suitable voltage divider, with a few pins left over for LED indicators (charging/ready, probably will use a bi-colour LED here). Any reason why I couldn't/shouldn't give this a shot? I reckon it'd be a good way to get used to the device and start building circuits around it. Already got the necessary Arduino cores (I think!) and have read up on programming it using a board I already have as the ISP.

Yes, the 85 can replace the 555, LM311, and a few of the discrete components (those used to set the 555 frequency)--in other words the left half of the circuit. Also, you do not need to wind an inductor. Commercial inductors in the range specified are readily available.

For making switching converters,buck, boost or inverting , for general use this IC MC34063 can do what you need with very few external components.
Design tool here which gives all the component values needed.
http://www.nomad.ee/micros/mc34063a/

Thanks for the reply! As for the inductors, yeah I could buy them... but I salvaged about a mile of copper wire of varying diameters from some old CRT monitors, and have recently bought a cheap LCR meter, so that's more of an exercise than a necessity :smiley: Keeps me out of trouble for a few hours :wink:

mauried:
For making switching converters,buck, boost or inverting , for general use this IC MC34063 can do what you need with very few external components.
Design tool here which gives all the component values needed.
MC34063A design tool

Thanks for the link mauried, but I think my application requires a LOT more current than that chip can handle. And I do want my caps to charge in less than a week :smiley: I already have circuits built that can produce a few KV of p.d. but they are useless for shoving any real current around.