>AFAIK TECs require the smoothest current they can get,
>which is why I started looking into multi-phase designs.
>
>If I'm mistaken about the preference of TECs to have flat
>current, then I can certainly use a single-phase PWM,
>however, my concern is then that the ripple current from
>my 12V supply will be quite large, which I want to avoid.
>
>So I still like the idea of a multi-phase controller.  What
>I want to avoid is using two PWMs with a sync controller and
>a load-share controller.  I'd much rather use a converter
>that is designed to use multiple phases.

My understanding is you cannot control a TEC by feeding it a PWM waveform,
but filtering that waveform through a normal LC filter, such as that used on
the output of switchmode supplies gives a smooth enough DC for the purpose.

I think you would get away with using some of the high current capable
regulator chips. Have a look at Linear Technology Design Note 215 which
discusses building a 3.3V 100A converter around multiple LTC1629 chips. For
<35A you get away with one chip and 2 buck stages. I suspect this will be
about the only way to do what you want as pretty well all the multiphase
chips I am aware of are designed for feeding the very low voltage processor
chip cores at very high currents.

-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist