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dc-dc step up circuits in series?

duke37

Jan 9, 2011
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Probably not.

If it is a step up convertor using an inductor, then the output and input will have a common ground (earth) and stacking two outputs will short the power supply.

If the inductor is in reality a transformer with the output isolated from the input (unlikely) then it should be possible. Why not ask the suppliers a question?
 

vCraZz

Jun 12, 2011
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i tried but there answer wasnt very helpfull
i also asked for the boards diagram, they wouldnt give it to me :(
 

vCraZz

Jun 12, 2011
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i get it now. its a buck step up with a common nutural
thanks i now know what to look for
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Jan 21, 2010
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Yes, what you'd be looking for is a completely isolated dc-dc converter.

They're not that hard to come by, but they tend to have a much lower power rating for their size when compared to a buck regulator.

I have some that have 1000V or 1500V of isolation (can't remember at the moment). I could easily string up a stack of the outputs of those in series -- maybe 2 of them to get an isolated split power supply.

They were very common in the older coax style ethernet (10 Base2, 10 base-5, again, from memory) cards because they needed to maintain isolation. 10-baseT, 100base-T, 1000base-T use transformers at both ends of the cable, so they are intrinsically isolated.
 

vCraZz

Jun 12, 2011
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will have a look out for some
not sure if im going to find one with variable current though
 

vCraZz

Jun 12, 2011
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ok would you guys know of a step up transformer circuit capable of 30v and vairable current of 0 up to 1amp
the circuit is to drive an RGB led (i need the variable current for tunning colours)
im looking for anything from a pre-assembled circuit to circuit schematics
i want the circuit to be battery powered and have found some cheap 12v, 2A lithium batteries
so i would like to use them if possible
 
Last edited:

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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We really need to ask you what you're intending driving (required voltage/current, and what you already have (voltage/current).

I'd like to be sure that what you're doing is actually a solution.
 

vCraZz

Jun 12, 2011
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for the battery/batteries either
1x 12v 1800mA lithium
or
10x 1.2v 3000mA NI-MH
depending on how much current i need
 
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BobK

Jan 5, 2010
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for the battery/batteries either
1x 12v 1800mA lithium
or
10x 1.2v 3000mA NI-MH
depending on how much current i need
Well, at 100% efficiency, your first battery would last 21 minutes and your second would last 36 minutes.

Realistically, multiply these by about .8 to get 17 or 29 minutes.

Is that what you are expecting?

Bob
 
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