Voltage boost IC?

[Shaocaholica]

I'm also looking for a voltage boost IC to get 5V-12V from 4xAA cells. I don't need a ton of amps but 4W would be nice.

It doesn't have to be the same part for the whole range(ie. one IC for 5V and another for 12V).

I don't think the output has to be terribly regulated. Here's what I'm trying to drive(2 circuits):

http://www.oatleyelectronics.com/kits/k190.html

 

[leduk]

LM2577T good for 3A. If you want to build yourself.

Also there are discrete enclosed DC-DC converters which may have suitable inputs and outputs 5V and 12V. They are expensive.

Thinking about it, an AT/ATX PSU would do the job too.

Cheers

 

[Lucien]

From 4 AA cells, if you're using NiMH, that'll be 4.8 V nominally, and drawing 4 W of power means a 833 mA current draw. With alkalines, you'd have 6 V nom, for 667 mA current draw. But the alkalines probably wouldn't last as long, they're not as good for high current drains.

There's plenty of chips out there that should do what you need, 5 V and 12 V are pretty common. A good starting point might be to look at National Semiconductor, specifically they do have a range called Simple Switchers, but I can't seem to find the home page for that.

There's also Linear Technology, Maxim and a whole bunch more.

Note that for 5 V output, you have take into account what your input voltage is to begin with. If you're running off alkalines, a low dropout (LDO) linear regulator might be an option instead of a switcher.

 

[TMorita]

Take a look at the Anyvolt and Anyvolt mini:

http://www.dimensionengineering.com/

Toshi