custom LiFePO4 charging circuit help

[billhowl]

Well, digikey does have the lm3420, but what I didn't know is that it's surface mount. At the moment I have neither the means to work with surface mount nor the money to buy the tools to do so.

Hi z.s.tar.gz, I think you can replace the LM2575 with your MC34063 and the LM3420 with TL431 plus some add on circuit. please check out.

http://electronics-diy.com/electronic_schematic.php?id=729
In Figure 1, an MC34063A switching regulator and an MC33342 NiMH battery-charger IC combine to generate from an unregulated power supply a 600-mA battery charger for one to four NiMH cells.
http://www.edn.com/article/CA56207.html
http://www.edn.com/articles/pdfs/EDN/20001221/26di11.pdf
http://www.edn.com/contents/images/122100di.pdf

[z.s.tar.gz]

I've actually run into several new problems.
For the sake of copy and pasting everything again, here's my other post: http://www.societyofrobots.com/robotforum/index.php?topic=9965.0