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DC Step Down

05/12/2010 8:24 AM

Hi friends, I'm doing one project, for that I need to step down or step up the dc voltage that I generated, is there anything to do this, other than buck or boost converter.

If there is nothing other than these two, give me some information about these two, whether they are available in the market.

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Anonymous Poster
#1

Re: DC step down

05/12/2010 8:31 AM

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.

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Anonymous Poster
#2
In reply to #1

Re: DC step down

05/12/2010 9:34 AM

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

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#4
In reply to #2

Re: DC step down

05/12/2010 11:00 AM

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!)

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#3

Re: DC Step Down

05/12/2010 10:14 AM

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....

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Commentator

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#5
In reply to #3

Re: DC Step Down

05/12/2010 9:49 PM

i want to step up 1.2v to 3.2v

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#6
In reply to #5

Re: DC Step Down

05/12/2010 10:44 PM

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.

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#9
In reply to #6

Re: DC Step Down

05/13/2010 6:30 AM

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

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#8
In reply to #5

Re: DC Step Down

05/13/2010 3:42 AM

Ok that's one of many important parameters. Any idea how much power, how stable your 1.2V input is and how stable the 3.2V output? Also the total amount of energy would be nice to know. Because you could just use an amplifier with a gain of 3.2/1.2. Now how does the amplifier get its power is another question. If the sole source of power is your 1.2V, then some very clever work with a switching supply will have to be done. You will certainly have to know how much current can be drawn from this supply and with this low of a power voltage your wire resistances.

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#7

Re: DC Step Down

05/13/2010 1:55 AM

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

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#10

Re: DC Step Down

05/13/2010 4:21 PM

Go to www.national.com

LM2621 has a minimum input voltage of 1.2V

LM2623 has a minimum input voltage of 0.8V

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#11

Re: DC Step Down

05/13/2010 11:22 PM

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" ; )
--------------------------------------------------
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

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#12
In reply to #11

Re: DC Step Down

05/14/2010 8:51 AM

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.

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