DC-DC Converter with isolation

[Tomasz Radziszewski]

I need a DC-DC converter 5V-5V with output isolatet from input. I found such
devices only on ST webpages. Please tell me, who more makes such things or
how should I search to exclude non-isolated converters.

 

[Roger Hamlett]

"Tomasz Radziszewski" <ufol@student.uci.agh.edu.pl> wrote in message
news:bn8bcr$28g$1@atlantis.news.tpi.pl...

I need a DC-DC converter 5V-5V with output isolatet from input. I found
such
devices only on ST webpages. Please tell me, who more makes such things or
how should I search to exclude non-isolated converters.
Traco, Recom, Lambda, C&D technologies, Power-One. There are dozens of

companies making such converters in a range of sizes. The smaller units
often use a 'standard' footprint, and are interchangeable between many of
the manufacturers. Just use the word 'isolated', in your search...
For small units (1W), this sheet gives one of the commonest models around:
http://www.fse-power.com/pdf/nme.pdf

Best Wishes

 

Tomasz Radziszewski wrote:

I need a DC-DC converter 5V-5V with output isolatet from input. I found such
devices only on ST webpages. Please tell me, who more makes such things or
how should I search to exclude non-isolated converters.

If you need only 1, and if efficiency and power are of
no concern (you didn't mention either), you can build
one easily. 2 npn xsistors. Collectors to primary
of center tapped audio transformer (center tap to positive
through a ~47 ohm current limiting resistor), and each
collector also to a ~4.7k resistor. The other end of
each resistor to the opposite transistor base. Emitters
to negative. Secondary of transformer to bridge rectifier,
filter cap and zener or 7805. I needed one for dual, isolated
9v outputs that had to fit in the volume of a single 9v
battery and found a modem transformer (600:600 ohm) with CT
primary and dual secondaries. Works fine, but I need only
a couple of ma. I tested it, and it will provide at least
9v on both secondaries at at least 10 ma on both secondaries
simultaneously. I imagine you could get appreciably greater
current off an audio xformer. You can choose a different
value for the current limiting resistor to get more
primary power - you could possibly eliminate it entirely.

Doubtless you will get better efficiency if you find one
made for sale .

 

[Henry]

If you want 1 to 2 watts only then use the DIP package types from Burr-Brown
(now TI). It's a great part!
- Henry

Tomasz Radziszewski schrieb in Nachricht ...

I need a DC-DC converter 5V-5V with output isolatet from input. I found
such
devices only on ST webpages. Please tell me, who more makes such things or
how should I search to exclude non-isolated converters.