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I need 5 independent power supplies ?

Started by Rodo May 13, 2004
Hi all,

I need 5 independent power supplies. I can use a single transformer with 5
secondary windings but I haven't been able to find one (Vin=115vac ok). Is
there a chip that can do the same ? Vout=24vdc, max Iout 20 mA (each).

Thanks


In article <gJVoc.193988$L31.60101@nwrddc01.gnilink.net>,
Rodo <dsp1024@yahoo.com> wrote:
>Hi all, > >I need 5 independent power supplies. I can use a single transformer with 5 >secondary windings but I haven't been able to find one (Vin=115vac ok). Is >there a chip that can do the same ? Vout=24vdc, max Iout 20 mA (each).
Maybe we need to back it up a bit. Why do you need 5 independant power supplies? Do the circuits need to be electrically isolated from each other? 5 secondaries is a stretch. So why is the isolation necessary? BAJ
"Rodo" <dsp1024@yahoo.com> wrote in message
news:gJVoc.193988$L31.60101@nwrddc01.gnilink.net...
> Hi all, > > I need 5 independent power supplies. I can use a single transformer with 5 > secondary windings but I haven't been able to find one (Vin=115vac ok). Is > there a chip that can do the same ? Vout=24vdc, max Iout 20 mA (each).
Get a transformer made. Leon
On Fri, 14 May 2004 01:58:36 GMT, Rodo wrote:
> Hi all, > > I need 5 independent power supplies. I can use a single transformer with 5 > secondary windings but I haven't been able to find one (Vin=115vac ok). Is > there a chip that can do the same ? Vout=24vdc, max Iout 20 mA (each).
A transformer, rectifier and capacitor and 5 500mW or 1W DC-DC converters? -- Trevor Barton
Rodo wrote:

> Hi all, > > I need 5 independent power supplies. I can use a single transformer with 5 > secondary windings but I haven't been able to find one (Vin=115vac ok). Is > there a chip that can do the same ? Vout=24vdc, max Iout 20 mA (each). > > Thanks
At the power rating you have the transformer cores in RS would be OK for winding your own. I have made several transformers of this configuration myself (although using a lower input voltage) in a switcher for a DC-DC converter. Unlike the un-imaginative respondent I can guess why you need 5 isolated supplies. -- ******************************************************************** Paul E. Bennett ....................<email://peb@a...> Forth based HIDECS Consultancy .....<http://www.amleth.demon.co.uk/> Mob: +44 (0)7811-639972 .........NOW AVAILABLE:- HIDECS COURSE...... Tel: +44 (0)1235-811095 .... see http://www.feabhas.com for details. Going Forth Safely ..... EBA. www.electric-boat-association.org.uk.. ********************************************************************
On Fri, 14 May 2004 01:58:36 GMT, "Rodo" <dsp1024@yahoo.com> wrote:

>Hi all, > >I need 5 independent power supplies. I can use a single transformer with 5 >secondary windings but I haven't been able to find one (Vin=115vac ok). Is >there a chip that can do the same ? Vout=24vdc, max Iout 20 mA (each). > >Thanks >
C&D Technologies makes small isolated DC-DC converters that could be used for this. -- Peter Bennett VE7CEI email: peterbb4 (at) interchange.ubc.ca GPS and NMEA info and programs: http://vancouver-webpages.com/peter/index.html Newsgroup new user info: http://vancouver-webpages.com/nnq
On Fri, 14 May 2004 01:58:36 GMT, the renowned "Rodo"
<dsp1024@yahoo.com> wrote:

>Hi all, > >I need 5 independent power supplies. I can use a single transformer with 5 >secondary windings but I haven't been able to find one (Vin=115vac ok). Is >there a chip that can do the same ? Vout=24vdc, max Iout 20 mA (each). > >Thanks
You could always use 3 transformers with two secondaries each. Do note that the secondary-to-secondary isolation (both voltage and capacitive coupling) is usually inferior to the primary-to-secondary isolation (depending on the construction of the transformer). Often the maximum voltage rating is not stated. Best regards, Spehro Pefhany -- "it's the network..." "The Journey is the reward" speff@interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
On Fri, 14 May 2004 18:48:37 +0100, "Paul E. Bennett"
<peb@amleth.demon.co.uk> wrote in comp.arch.embedded:

> Rodo wrote: > > > Hi all, > > > > I need 5 independent power supplies. I can use a single transformer with 5 > > secondary windings but I haven't been able to find one (Vin=115vac ok). Is > > there a chip that can do the same ? Vout=24vdc, max Iout 20 mA (each). > > > > Thanks > > At the power rating you have the transformer cores in RS would be OK > for winding your own. I have made several transformers of this > configuration myself (although using a lower input voltage) in a > switcher for a DC-DC converter. > > Unlike the un-imaginative respondent I can guess why you need 5 > isolated supplies.
...and I can guess that your guess is wrong! :) -- Jack Klein Home: http://JK-Technology.Com FAQs for comp.lang.c http://www.eskimo.com/~scs/C-faq/top.html comp.lang.c++ http://www.parashift.com/c++-faq-lite/ alt.comp.lang.learn.c-c++ http://www.contrib.andrew.cmu.edu/~ajo/docs/FAQ-acllc.html