>> Note Page 37, A 4.5V to 5.5V Input, 12V/15A Output 4-Phase
>> Boost Converter Application Circuit, that they suggest two whole
>> circuits in parallel
>>
>> Would this be the preferred and least smokey method ?
>
> As opposed to what?

Beefing up a 2-phase circuit, which is what my OP was about

> Four phases with a 90 degree pja\\hase offset gives better again
> results. Double the above again.

4-Phase Boost Converter Delivers 384W with no Heat Sink

http://cds.linear.com/docs/Design%20Note/dn453f.pdf

> If your Vin is higher the task gets easier.
> You need to provide actual requirement to allow good what-if ing.
>
> What Vin.
> What pout.
> What Vout ...?

One application is to extract power from solar panels. I have an
MPPT 3-stage lead battery charger which doesn't have an input
booster, so when panel < battery, charging stops. There's 50W
of panel (12V nominal) at the moment but the plan is to add more

Panel voltage peaks around 21V in full sun and obviously drops
with cloud or at sunset/sunrise, even with tracking, and there's still
useable charging wattage if the voltage can be brought up to 15V

Page 36 and Page 37 circuits are both pretty close

http://cds.linear.com/docs/Datasheet/3862fb.pdf

and could be configured for > 8V to 15V

It might be better to make several small (8A - 10A) modules, eg
one per panel (< 100W), rather than get too Tim "Tool Time" Taylor
(argh-argh-argh-argh-argh) and try to control a lot of current with
a few more-expensive ones
--=20
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