SMPS input 110VDC to 12VDC

[zab]

All you require is an smps ic. & high side fet driver. Then you can make buck circuit even  from 600 v to 12v dc easily.
But remember it  is risky.

[vantusaonho]

Please let me know how to calculate the voltage rise

[pickit2]

why don't you download the data sheets, do a bit of reading, first.
save us all from pain, why not buy one from ebay and dissect it and post your findings.

you don't even take advice, so why should we spoon feed you, do some research yourself...

[vantusaonho]

why don't you download the data sheets, do a bit of reading, first.
save us all from pain, why not buy one from ebay and dissect it and post your findings.

you don't even take advice, so why should we spoon feed you, do some research yourself...

I don't need anything spoon feed, I have already read datasheet, tut, ebook, paper thesis, journal. But they are diffirent from each others. It take me very confusing. Now I need a right thing of experimental person. If I do research myself, this forum is not mean. If  someone have experimental in smps, but don't share theirs. This forum what for?

[pickit2]

I don't need anything spoon feed, I have already read datasheet, tut, ebook, paper thesis, journal. But they are diffirent from each others. It take me very confusing. Now I need a right thing of experimental person. If I do research myself, this forum is not mean. If  someone have experimental in smps, but don't share theirs. This forum what for?

so why not find one that works, sounds as if you do need spoon feeding, "If  someone have experimental in smps, but don't share theirs. This forum what for?" your asking for a full tried and tested, solution, but don't take advice.

asking questions like "Please let me know how to calculate the voltage rise" don't make sense, voltage rise where? line or feedback.

Do you even know what dangers are involved, in such a product, your skill levels are not just there.

I have 10 plus such smps as part of products, placed in market place, by my employer sorry I can't give full details of products.
But they follow very close to the data sheet and Application Notes.

http://www.powerint.com/en/products/product-documents
http://www.powerint.com/sites/default/files/product-docs/miniapplianceweb_PSG.pdf
- - - - - (part of spoon feed) - - - - -

[vantusaonho]

Sigh!!!!!!!!!!!!!!!    I am a newbie in smps. And I am in Vietnam where can not buy anything in foreign. I can only buy some IC from China. How to let me try with Powerint product. I use UC3842 because I can get it. I almost have all design for myself but there are some problem with voltage rise when the switch off coil.

[pickit2]

the uc3842 is close to powerint devices, so circuit is about the same.
 
do you have a panasonic service agent, in your local, ask then for some scrap boards from microwave oven, not the inverter type.
they have powerint devices, have a 12-15Vdc at 1 to 2. plus 5v, get the apps notes: and you have all the parts to make a smps and no worry about transformer build.

[solutions]

What's it for and how many?

What's wrong with using these (not an endorsement, just an example)?



http://store.fundamentallogic.com/ecom/index.php?main_page=product_info&products_id=491

I would think you have better things to do than design a power supply and wind your own transformer (I find it hard to believe you can get your hands on the cores where you are), especially when you can pick one up CHEAPER than the parts you'll buy for your own design...cheaper, in fact, than the bare circuit board....

And for prototyping, you can just buy a portable hard drive, which uses a 12V 1A, 1.5A, or 2A wall wart.

[Ichan]

And I am in Vietnam where can not buy anything in foreign.

You have to find a way to break that boundary through, years ago i am on the same situation with you.

Anyway, learning from cheap power supply is worthy - i ever found one which only use several bipolar transistor.

-ichan