What range of frequencies are you running the EL lamp at? Would it be
possible to just run that frequency through the magnetics? If so, you
could do a simple step up transformer with the center tap of the primary
tied to Vcc and have a couple transistors pull each end low alternately. A
PIC could drive a couple FETs or bipolars for that purpose.

For boost converters, I like the LT1370, but for this high a voltage, I'd
use it as a flyback converter, getting voltage gain from the turns ratio.
I just did a multivoltage supply using the LT1370 as a flyback converter.
Works nice!

Another approach for low current voltage multiplication is the
diode/capacitor voltage multiplier circuits. Drive them with low voltage
AC and out comes multiplied DC.

If the magnetics doesn't get too huge due to low frequency, I like the
forward converter discussed first. You're converting DC to AC and you're
done. In the others, you're generating AC to boost the voltage, then back
to DC, then you need a half or full bridge to generate AC again.

Harold

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