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dc-dc converter chip for phantom power

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Anonymous
July 20, 2004 7:47:49 PM

Archived from groups: rec.audio.pro (More info?)

Howdy all......:-)

Looking for recommendations for a dc-dc converter (12vdc input/48vdc
output) integrated circuit so that I can roll my own portable phantom
supply.

Found one such beastie at:

http://www.recom-international.com/html/euroline.htm
RxxTR244872 In 5, 12 Out 24, 48, 72

Any others that fit the bill? Thanks! :-)
Anonymous
July 20, 2004 7:47:50 PM

Archived from groups: rec.audio.pro (More info?)

Lawrence Lucier <llucier@shaw.ca> wrote:
>Howdy all......:-)
>
>Looking for recommendations for a dc-dc converter (12vdc input/48vdc
>output) integrated circuit so that I can roll my own portable phantom
>supply.
>
>Found one such beastie at:
>
>http://www.recom-international.com/html/euroline.htm
>RxxTR244872 In 5, 12 Out 24, 48, 72
>
>Any others that fit the bill? Thanks! :-)

There are plenty of them and they are all evil. I have used the shielded
ones from Endicott Research and they are okay for noncritical applications
where you can live with some RF trash. All of them are going to require
some extensive filtering on both the outputs AND the inputs.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Anonymous
July 20, 2004 7:47:50 PM

Archived from groups: rec.audio.pro (More info?)

"Lawrence Lucier" <llucier@shaw.ca> wrote in message
news:F8bLc.63642$Mr4.39806@pd7tw1no
> Howdy all......:-)
>
> Looking for recommendations for a dc-dc converter (12vdc input/48vdc
> output) integrated circuit so that I can roll my own portable phantom
> supply.

You might want to take a look at the discrete-component alternatives:

One approach is to run a voltage multiplier off of an existing power
transformer winding,

http://sound.westhost.com/project96.htm

http://www.symetrixaudio.com/tech_support/schematics/20...

http://www.uneeda-audio.com/phantom/phan01.gif

the other is to use a switchmode multiplier running off of an existing DC
supply.

http://www.paia.com/tubehsch.pdf

http://www.rolls.com/data/pb224man.pdf
Related resources
Anonymous
July 21, 2004 1:04:38 AM

Archived from groups: rec.audio.pro (More info?)

On Tue, 20 Jul 2004 15:47:49 GMT, in rec.audio.pro you wrote:

>
>Howdy all......:-)
>
>Looking for recommendations for a dc-dc converter (12vdc input/48vdc
>output) integrated circuit so that I can roll my own portable phantom
>supply.
>
>Found one such beastie at:
>
>http://www.recom-international.com/html/euroline.htm
>RxxTR244872 In 5, 12 Out 24, 48, 72
>
>Any others that fit the bill? Thanks! :-)
if you want to roll your own, try
LT1533 ultralow Noise1A Switching Regulator from linear.com
http://www.linear.com/pdf/1533f.pdf



martin

Serious error.
All shortcuts have disappeared.
Screen. Mind. Both are blank.
Anonymous
July 22, 2004 1:59:23 AM

Archived from groups: rec.audio.pro (More info?)

martin griffith wrote:
> On Tue, 20 Jul 2004 15:47:49 GMT, in rec.audio.pro you wrote:

> LT1533 ultralow Noise1A Switching Regulator from linear.com
> http://www.linear.com/pdf/1533f.pdf

That's what's used in AKG PT pocket transmitters, FWIW.

geoff
Anonymous
July 22, 2004 1:59:24 AM

Archived from groups: rec.audio.pro (More info?)

On Wed, 21 Jul 2004 21:59:23 +1200, Geoff Wood <geoff@paf.co.nz-nospam>
wrote:
> martin griffith wrote:
>> On Tue, 20 Jul 2004 15:47:49 GMT, in rec.audio.pro you wrote:
>
>> LT1533 ultralow Noise1A Switching Regulator from linear.com
>> http://www.linear.com/pdf/1533f.pdf
>
> That's what's used in AKG PT pocket transmitters, FWIW.
>
> geoff
>
>

Any reason why you're not thinking linear instead of switching?
Anonymous
July 22, 2004 1:59:25 AM

Archived from groups: rec.audio.pro (More info?)

U-CDK_CHARLES\\Charles <cdkrug@aol.com> wrote:
>On Wed, 21 Jul 2004 21:59:23 +1200, Geoff Wood <geoff@paf.co.nz-nospam>
>wrote:
>> martin griffith wrote:
>>> On Tue, 20 Jul 2004 15:47:49 GMT, in rec.audio.pro you wrote:
>>
>>> LT1533 ultralow Noise1A Switching Regulator from linear.com
>>> http://www.linear.com/pdf/1533f.pdf
>>
>> That's what's used in AKG PT pocket transmitters, FWIW.
>
>Any reason why you're not thinking linear instead of switching?

If you are wanting to get 48V from a battery supply, you either need
a lot of batteries or a switcher.

Personally, I tend to go the route of using a lot of batteries.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Anonymous
July 22, 2004 1:59:26 AM

Archived from groups: rec.audio.pro (More info?)

On 21 Jul 2004 10:55:38 -0400, Scott Dorsey <kludge@panix.com> wrote:
> U-CDK_CHARLES\\Charles <cdkrug@aol.com> wrote:
>>On Wed, 21 Jul 2004 21:59:23 +1200, Geoff Wood <geoff@paf.co.nz-nospam>
>>wrote:
>>> martin griffith wrote:
>>>> On Tue, 20 Jul 2004 15:47:49 GMT, in rec.audio.pro you wrote:
>>>
>>>> LT1533 ultralow Noise1A Switching Regulator from linear.com
>>>> http://www.linear.com/pdf/1533f.pdf
>>>
>>> That's what's used in AKG PT pocket transmitters, FWIW.
>>
>>Any reason why you're not thinking linear instead of switching?
>
> If you are wanting to get 48V from a battery supply, you either need
> a lot of batteries or a switcher.
>
> Personally, I tend to go the route of using a lot of batteries.
> --scott

Oh BATTERY . .missed that. Four car batteries'd do it. Or perhaps
better four RV "Deep Cycle" batteries. Probably last four-five years.
Anonymous
July 22, 2004 1:59:27 AM

Archived from groups: rec.audio.pro (More info?)

U-CDK_CHARLES\\Charles <cdkrug@aol.com> wrote:
>
>Oh BATTERY . .missed that. Four car batteries'd do it. Or perhaps
>better four RV "Deep Cycle" batteries. Probably last four-five years.

I normally use five 9V stacks, which gives you 45V, or six 9V stacks
plus a 48V series regulator (which more than doubles the usable lifetime
if you are using alkalines). It's kind of bulky, though.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Anonymous
July 22, 2004 5:29:15 PM

Archived from groups: rec.audio.pro (More info?)

Scott Dorsey <kludge@panix.com> wrote:

> If you are wanting to get 48V from a battery supply, you either need
> a lot of batteries or a switcher.

> Personally, I tend to go the route of using a lot of batteries.

How about a combination? Rechargeables fed by a dc-dc converter built
to less critical specs?

While 9v rechargeables still aren't good enough to handle most applications,
I would think that a low current demand like phantom power would be
do-able.

Rob R.
Anonymous
July 22, 2004 5:29:16 PM

Archived from groups: rec.audio.pro (More info?)

Rob Reedijk <reedijk@hera.med.utoronto.ca> wrote:
>Scott Dorsey <kludge@panix.com> wrote:
>
>> If you are wanting to get 48V from a battery supply, you either need
>> a lot of batteries or a switcher.
>
>> Personally, I tend to go the route of using a lot of batteries.
>
>How about a combination? Rechargeables fed by a dc-dc converter built
>to less critical specs?

Maybe, but you're still carrying around a big box of batteries. In fact,
since the current demand is so low, even cheap alkalines will last so long
that it's not worth even worrying much about using rechargeables.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Anonymous
July 30, 2004 3:20:33 AM

Archived from groups: rec.audio.pro (More info?)

Scott Dorsey <kludge@panix.com> wrote:

> Rob Reedijk <reedijk@hera.med.utoronto.ca> wrote:
> >Scott Dorsey <kludge@panix.com> wrote:
> >
> >> If you are wanting to get 48V from a battery supply, you either need
> >> a lot of batteries or a switcher.
> >
> >> Personally, I tend to go the route of using a lot of batteries.
> >
> >How about a combination? Rechargeables fed by a dc-dc converter built
> >to less critical specs?
>
> Maybe, but you're still carrying around a big box of batteries. In fact,
> since the current demand is so low, even cheap alkalines will last so long
> that it's not worth even worrying much about using rechargeables.

In that case, why not use one of those 67-volt camera batteries that
looks like a fat AA cell? They sell them at Batteries Plus and
probably Radio Shack. How long do you suppose one of those would last?

ulysses
Anonymous
July 30, 2004 1:06:17 PM

Archived from groups: rec.audio.pro (More info?)

In article <290720042320335085%ulyssesnospam@rollmusic.com>,
Justin Ulysses Morse <ulyssesnospam@rollmusic.com> wrote:
>Scott Dorsey <kludge@panix.com> wrote:
>
>> Rob Reedijk <reedijk@hera.med.utoronto.ca> wrote:
>> >Scott Dorsey <kludge@panix.com> wrote:
>> >
>> >> If you are wanting to get 48V from a battery supply, you either need
>> >> a lot of batteries or a switcher.
>> >
>> >> Personally, I tend to go the route of using a lot of batteries.
>> >
>> >How about a combination? Rechargeables fed by a dc-dc converter built
>> >to less critical specs?
>>
>> Maybe, but you're still carrying around a big box of batteries. In fact,
>> since the current demand is so low, even cheap alkalines will last so long
>> that it's not worth even worrying much about using rechargeables.
>
>In that case, why not use one of those 67-volt camera batteries that
>looks like a fat AA cell? They sell them at Batteries Plus and
>probably Radio Shack. How long do you suppose one of those would last?

Not as long. Because they are lead-acid batteries, they have self-discharge
issues so they eventually go bad on the shelf.

I built a supply for the B&K lab mikes using three of them to get the 200V
polarization and plate voltages, and they did well, though.

Oh yes, and they are a little bit bigger than five 9V batteries.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
August 4, 2004 9:32:50 PM

Archived from groups: rec.audio.pro (More info?)

In article <290720042320335085%ulyssesnospam@rollmusic.com>, Justin Ulysses Morse <ulyssesnospam@rollmusic.com> wrote:
>Scott Dorsey <kludge@panix.com> wrote:
>
>> Rob Reedijk <reedijk@hera.med.utoronto.ca> wrote:
>> >Scott Dorsey <kludge@panix.com> wrote:
>> >
>> >> If you are wanting to get 48V from a battery supply, you either need
>> >> a lot of batteries or a switcher.
>> >
>> >> Personally, I tend to go the route of using a lot of batteries.
>> >
>> >How about a combination? Rechargeables fed by a dc-dc converter built
>> >to less critical specs?
>>
>> Maybe, but you're still carrying around a big box of batteries. In fact,
>> since the current demand is so low, even cheap alkalines will last so long
>> that it's not worth even worrying much about using rechargeables.
>
>In that case, why not use one of those 67-volt camera batteries that
>looks like a fat AA cell? They sell them at Batteries Plus and
>probably Radio Shack. How long do you suppose one of those would last?
>
>ulysses
Small 12v Gellcell batteries hooked together inseries 4x12 to equal your 48V
would do the trick
!