DC Step Down

This is the practical way of doing it.

depending on where you are, you may search. It is available everywhere ( eg any inverter does half of it, the other half will be the rectifier on output stage).

But it all depends upon what is your input and output voltages.

Yes,that is the only way to do it: Inverter/Rectifier.

Well, probably the only economical way, depending on power output. You can always drop voltage with a diode/zener, resistor, etc. I can recall an old, rather elegant system with a motor-generator set I had to decipher as a student, also the Ward-Leonard (was that DC-DC?) systems for high-power applications.

(sorry, had a hard day, being a bit facetious here!)

This is a method to do this but the only thing given here is that you wish to change a DC voltage. You're not even sure if this voltage must increase or decrease. We cannot read or transmit thoughts here without typing. If we could....

i want to step up 1.2v to 3.2v

Those are a bit too small. With diode drops (you have to have them) of 0.6V _{(as I remember is it still 0.6V?)} you don't have much left out.

He wants to STEP UP from 1.2 to 3.2V (!?)

Yes! you can do that by...reasoning!

hi, i am also recently working with a 50DC-5>Vdc circuit MAX5033, but come across with some bugs.. i think.. ~~ shooting it now.

You may also take a lookin Maxim, Texas Insturment, look for step down IC.
note on output load current, yes. stabilty, how many ripples, you expect on the output?

You Take a look in "max1947" ; )
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Low Input (0.7V) and Output (1.8V) Voltage Capability
Internal Synchronous Rectifier
High 94% Efficiency
Fixed Output Voltages: 1.8V, 2.5V, 3V, and 3.3V

I expect only 37.2 ripples from a well designed Lirpa Labs audio system. Where's Pigpen when you need him? He liked ripple. Who's rambling in an incoherent manner?

Can you say "reflection"? Sure you can.