Recommend an LED Driver

Hi all,

I am looking for an LED Driver IC (or a discrete circuit) that can power 8 to 16 white and 8-16 UV 5mm LEDs from 2 AA batteries (switching between the two sets). My main constraint is that the IC should be in a DIP package, not surface mount. Size is not that important. I could get something like the MicroPuck, but I prefer to build the circuit myself to learn more about boost converters.

I've looked at some manufacturers but most all of these are in SMT packages. Found a couple from Maxim-IC, the MAX633, MAX643 and the dual MAX743 I might be able to use.

A circuit or chip with a low battery indicator output would be a plus.

TIA

-- Dan

Maxim's probably your best bet for DIP package switchers ... everyone else has gone to SMT

An 'oldie but goodie' is TI / Motorola's MC33063A which is a switchmode controller with integerated switch ... but the controller and switch aren't tightly connected, so you use it to regulate all sorts of topologies (buck, boost, flyback, etc). It comes in a DIP8 package

The other nice thing about the 33063a is the very low frequency, making it easy to breadboard - the newer chips running at 300-1200 kHz tend to get a little glitchy on a breadboard.

Thanks, that's the kind of info I'm looking for. The chip you recommend requires 3V minimum, but I probably have room for 4 AA's instead of 2.

-- Dan