Hi.

I need to find a schematic 12V to 48V 4 Ampere DC to DC Converter

Someone told me that i can do that with a UC3843!

The think is that i can't find a schematic! (Or don't know how... Because i am new to electronics)

Can anyone help me?

 

I think there are boost converters that do this, if you want an IC. Alternatively, you can construct it yourself, search for joule thief, this is the simplest example of DC-to-DC conversion I have seen.

 

You probably could do it with a UC3843, which is an old Unitrode part now made by TI. I'm not sure why you'd pick this particular part, except you might have found one in an old PC SMPS.

The UC3843 data sheet doesn't have any cookbook boost converters, which will make it hard for you to design something.

I would suggest reading the data sheet and app notes for the Linear LT3782. It should give you a better understanding of a high power boost topology.

 

how about using voltage doubler circuits

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Khizer Naeem Mughal
IIUI

 

I suggest you answer that one yourself! - voltage doublers are really only low current.

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hi,
A quick look at the UC3843 datasheet says: Vmax=30v and Imax =1amp.

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Eric
"Good enough is Perfect"

PIC tutorials:
Gramo's: www.digital-diy.net/
Bill's: www.blueroomelectronics.com/

 

Not a problem, the input voltage is less than that, and the chip is only a driver - the chip is the least of his design worries!.

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Had look for any design data on the web, no success, its NOT recommended for new designs.

I appreciate its just a PW driver, but the OP has been told that he can use the device, he can,
BUT it requires additional power transistors and supporting circuitry and a design.

__________________
Eric
"Good enough is Perfect"

PIC tutorials:
Gramo's: www.digital-diy.net/
Bill's: www.blueroomelectronics.com/

 

As does any design he chooses to make! - it's not really a trivial task - the obvious (and critical) part being the transformer or inductor (depending on design type).

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PIC programmer software, and PIC Tutorials at:
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As always, The OP has not said exactly what he is trying to do!
They way he describes the requirement, I suspect he is planning to use a 12V battery?? to drive a 48Vdc load.

With a little project background information, we maybe to advise him on a better solution.

Is it cold in Derbyshire today, frosty here?

__________________
Eric
"Good enough is Perfect"

PIC tutorials:
Gramo's: www.digital-diy.net/
Bill's: www.blueroomelectronics.com/

 

Cold, but not frosty.

__________________
PIC programmer software, and PIC Tutorials at:
http://www.winpicprog.co.uk

 

You might be able to a transformer from either a discarded UPS . A good idea would be to strip the audio section from an automobile power amp. They usually have a mosfet driven torroid and pwm chip built in. I have a Quad 100
watt per channel power amp that has a switcher that pumps +&- 85 volts into the amp its overload protected
and has two 30 amp fuses on the 12 volt feed often you can find these units cheap especially if your going to scrap th amp part and most of the time when they blow (except for polarity reversals) its usually the audio uot transistors that fail. etc....
EDGE

 

If I built this I would use a UC3824 + (BIG FET) and diode with center tapped coil (transformer).

You need something simple! This idea uses a LM2568-adj. (use heat-sink) The coil will be easier than a transformer, for you. For 12V in and 48 out you will only get 1amp but you can build 4 and run them in parallel. Build this and then we can talk about running 4 in parallel.

Attached Images

Image14.jpg (44.8 KB, 32 views)

 

Yep, the Simple Switcher range are pretty good devices. A lot of the manufacturers have software on their pages to allow you to 'design' buck boost convertors with their products.

 

Nigel Goodwin, I am having a red dot under my name what does that mean??

__________________
Khizer Naeem Mughal
IIUI