Richard H. wrote:
jack wrote:

why not consider a super-capacitor and d.c-d.c converter -- the converter
can loaf along with a very low duty cycle

linear tech had a very low loss dc-dc converter application note which
appeared in EDN in the Spring.

Yep, I'd planned to put an electrolytic near the load; it hadn't crossed
my mind to consider a super cap there. That could be a good match. I'll
look for the appnote.

Now, maybe a dumb question, but... DC-DC converter seems to be a generic
term in this area, with 'boost' and 'step-up' being more specific
synonyms (but I could be reading this all wrong). By DC-DC, do you mean
a linear regulator?

Though technically a linear regulator is a DC-DC converter, so is a resistor.
The term is not usually used for such devices.

Usually a DC-DC converter implies a device that through some switching technique
increases, or decreases the supplied voltage to some other level.

Generally, it is not practical to raise the DC supply voltage without some kind
of switching, or AC creating device, be it a motor-generator, an inverter,
or some scheme of charging capacitors in parallel, and discharging them in series...

-Chuck