Miniature transformer/stepdown-regulator

[Iman Habib]

Hi.

I have been looking for a miniature transformers design now for a
project but not found anything to my satisfaction. =(

What is need is 220VAC @ 60HZ -> 5VDC and a current output at around 1A
to 2A

Are there any single chip ICs on the market that do this?
(I do not need galvanic isolation)

Cheers
//iman

 

[Phil Allison]

"Iman Habib"

I have been looking for a miniature transformers design now for a
project but not found anything to my satisfaction. =(

What is need is 220VAC @ 60HZ -> 5VDC and a current output at around 1A
to 2A

Are there any single chip ICs on the market that do this?

(I do not need galvanic isolation)

** Really - explain how come.

Your whole post seems very sus.



......... Phil

 

[Iman Habib]

Your whole post seems very sus.

"sus" what? why?

I do not want galvanic isolation to reduce size.
It's a thingy that is supposed to fit inside a lamp switch socket
hole.
So i have very little space to work in.

//iman

 

[Phil Allison]

"Iman Habib"

"sus" what? why?

** Why did you just snip everything that mattered out of sight ?

Got a lot to hide?

I do not want galvanic isolation to reduce size.

** That is a BIG FUCKING DIFFERENCE from not *needing* it.

Answer the question I posted.

If you can.





.......... Phil

 

[Winfield Hill]

Iman Habib wrote...

I have been looking for a miniature transformers design now
for a project but not found anything to my satisfaction. =(

What is need is 220VAC @ 60HZ -> 5VDC and a current output
at around 1A to 2A

Are there any single chip ICs on the market that do this?
(I do not need galvanic isolation)

You have good triple insulation? If you really don't
need isolation you don't need a transformer. Look up
buck converters, you'll find plenty of 340vdc off-line
ICs. At this point I'm ready to list four or five key
considerations. But let's just say there are serious
pitfalls, it's best to hire an experienced engineer.

What's your project, tell us about it.

 

[Rob*]

Hi.

I have been looking for a miniature transformers design now for a
project but not found anything to my satisfaction. =(

What is need is 220VAC @ 60HZ -> 5VDC and a current output at around 1A
to 2A

Are there any single chip ICs on the market that do this?
(I do not need galvanic isolation)

Cheers
//iman

What's inside the switching chargers Nokia & others manufacture for
mobile/cell phones? Might be worth a starting point.

 

[Iman Habib]

There is no need for you to be impolite Phil.
I have nothing to hide so calm down.
Why are you being so suspicious?

I'm an EE student from Sweden that is just helping
out a friend of mine for some project. He wants to shove
a small computer and some other stuff into a switch/socket.
Don't ask me why he wants to do it. I don't even care
and its really not that fascinating to be honest.

Obviously you are not capable of helping me out
so I'll just wait and hope somebody else will give me a pointer.
Don't bother replying Phil if you are just going to swear and shout
at me.

Have a nice day (you seem to be in desperate need it)

//iman

 

[Iman Habib]

What's inside the switching chargers Nokia & others manufacture for

mobile/cell phones? Might be worth a starting point.

Yes. I am actually opening one right now. =)
But the little bugger is kind of hard to open.
Ah well.. time for the big hammer.

thanks
//Iman

 

[Iman Habib]

Sorry for the confusion win.
I really suck at using the right tehcnical words.
You are absolutley right.
I dont need a transformer.

What's your project, tell us about it.

As i said to phil. I am just helping
out a friend of mine for some project. He wants to shove
a small computer and some other stuff into a switch/socket.
Don't ask me why he wants to do it. I don't even care
and its really not that fascinating to be honest.

Anyway. I google around for "buck converters".
Thank you for your help.

//Iman

 

[Nico Coesel]

Sorry for the confusion win.
I really suck at using the right tehcnical words.
You are absolutley right.
I dont need a transformer.


As i said to phil. I am just helping
out a friend of mine for some project. He wants to shove
a small computer and some other stuff into a switch/socket.
Don't ask me why he wants to do it. I don't even care
and its really not that fascinating to be honest.

If it is a hobby project, I would design it with proper isolation. I
lost a good friend because he was also sure he didn't need the
isolation...

The biggest problem with buck converters is that you'll need a really
small on-time (approx 1.7%). This decreases efficiency and you'll need
to find a high voltage MOSFET which you can switch fast enough to meet
your requirements. Keep in mind the MOSFET must be able to conduct the
maximum current in the load.

 

[Bjarne Bäckström]

I'm an EE student from Sweden

Hej!

that is just helping
out a friend of mine for some project. He wants to shove
a small computer and some other stuff into a switch/socket.

There are quite a few applications that do about the thing you are
looking for, if you look at dimmer or phase controller application notes
on the controller chip manufacturers' pages. They usually use a small
capacitor for voltage division.

 

[Phil Allison]

"Iman Habib"

There is no need for you to be impolite Phil.

** Get fucked you bloody fake.

I have nothing to hide so calm down.
Why are you being so suspicious?

** Got any bombs tied to you ?

I'm an EE student from Sweden that is just helping
out a friend of mine for some project. He wants to shove
a small computer and some other stuff into a switch/socket.

** The get him to post here.

Meanwhile - YOU can **** off.

Don't ask me why he wants to do it. I don't even care

** You are an obliging criminal ass.

Obviously you are not capable of helping me out
so I'll just wait and hope somebody else will give me a pointer.
Don't bother replying Phil if you are just going to swear and shout
at me.

** You are a DAMN LIAR .




......... Phil

 

[Phil Allison]

"Iman Habib"


** Get fucked, you trolling GG ASS.







........ Phil

 

[Phil Allison]

"Iman Habib"

Yes. I am actually opening one right now. =)
But the little bugger is kind of hard to open.
Ah well.. time for the big hammer.

** You are a FUCKING Googlegroping LIAR !!!






......... Phil

 

[Phil Allison]

""Bjarne Bäckström""


** Gawd - another obliging wog fuckwit.

There are quite a few applications that do about the thing you are
looking for, if you look at dimmer or phase controller application notes
on the controller chip manufacturers' pages. They usually use a small
capacitor for voltage division.

** ROTFL.

One that gives several amps DC of the AC supply ?

The Tooth Fairy sells them.






......... Phil

 

[Winfield Hill]

Nico Coesel wrote...

If it is a hobby project, I would design it with proper
isolation. I lost a good friend because he was also
sure he didn't need the isolation...

We're sorry about your friend. As for Iman - he should
tell his friend our strong advice is that he remove the
conduit switch box, get out his saw and install a double
box. Then he can use safe small commercial power modules
such as those made by Astrodyne, http://www.astrodyne.com

 

[Fred Bloggs]

Hi.

I have been looking for a miniature transformers design now for a
project but not found anything to my satisfaction. =(

What is need is 220VAC @ 60HZ -> 5VDC and a current output at around 1A
to 2A

Are there any single chip ICs on the market that do this?
(I do not need galvanic isolation)

Single-chip ICs versus multi-chip ICs? Your "friend" would be
well-advised to loose you, you're worthless; talk about the blind
leading the blind. Why don't you try prototyping a beefed up variant of
this))
http://www.discovercircuits.com/PDF-FILES/offline5v.pdf

 

[[email protected]]

There is no need for you to be impolite Phil.

Phil does seem to have some kind of compulsion to be impolite. I want
to see if his rather restricted range of impoliteness has improved over
the past few months, so I'm intentionally provoking his ire.

I have nothing to hide so calm down.

A sensible request, addressed to someone who isn't responsive to sweet
reasonableness.

Why are you being so suspicious?

Paranoia might be a plausible explanation - though there are a bunch of
conditions associated with "rage attacks" whch migh explain Phil's
behaviour.

http://www.tourettesyndrome.net/rage_overview.htm

I'm an EE student from Sweden that is just helping
out a friend of mine for some project. He wants to shove
a small computer and some other stuff into a switch/socket.
Don't ask me why he wants to do it. I don't even care
and its really not that fascinating to be honest.

Obviously you are not capable of helping me out
so I'll just wait and hope somebody else will give me a pointer.
Don't bother replying Phil if you are just going to swear and shout
at me.

Have a nice day (you seem to be in desperate need it)

He is.

Still, he's probably right to warn you about the dangers of
non-isolated mains-driven circuits. They are only to be considered if
you know exactly what you are doing, and even then you have to keep in
mind how you circuit might be abused by someone who thought they knoew
exactly what they were doing. He's abused me roundly in the past for
not being as defensive in such matters as he would like, and while I
didn't think much of his logic, his rabid advocacy may raise enough
consciousness to save a few lives

 

[Iman Habib]

Well I would advise him to loose me to. =)

I am more used to play around with non lethal current/voltage levels so
I have unfortunately very little experience when it comes to making
anything that is supposed to be directly connected to a household AC
net. But I reasoned that it would be a good learning experience to read
a bit more about it and try to solve it instead of passing it on to
somebody else.

Of course I am aware of the dangers and have no intention of plugging
in anything before somebody (a teacher for eg) double-checks my
simulations/calculations.

Anyway I have already come across the schematic you pointed out but it
did not quite reach me needs.

Thanks anyway.

//iman

 

[Iman Habib]

The Astrodyne ultraminiature modular switching power supplies seem to
be a very sensible option. Actually it's a great option. Thank you
very much for the pointer.
I will advise my friend to use one of these.

But I will still pursue to learn more about switching power supplies
and try and implement one myself. It's best I get my hands a bit
dirty and learn something about this the sooner instead of later when
it may be in a more serious circumstance.

Again, thank you.

//iman