> | Voice:(480)460-2350 =9AFax: Available upon request | =9ABrass Rat =9A|
> | E-mail Icon athttp://www.analog-innovations.com| =9A =9A1962 =9A =9A |
>
> I love to cook with wine. =9A =9A Sometimes I even put it in the food.
translation:
Contact the manufacturer's name to get the key, or if the number is
small, it does not cost that much more to get custom coils with your
requirements.
but you knew that, right?
What's handy with google access is that when a posting comes up in
foreign language, I simply click above the message 'translate to
english' and voila!
looks like this originally:
bloggs.fredbloggs.f...@gmail.com View profile Translate to
English
More options May 12, 12:46 pm
=EB=CF=CE=D4=C1=CB=D4=D9 =CE=C1=C9=CD=C5=CE=CF=D7=C1=CE=C9=C5 =D0=D2=CF=C9=
=DA=D7=CF=C4=C9=D4=C5=CC=D1, =DE=D4=CF=C2=D9 =D0=CF=CC=D5=DE=C9=D4=D8 =CB=
=CC=C0=DE, =C9=CC=C9, =C5=D3=CC=C9 =C9=C8
=CB=CF=CC=C9=DE=C5=D3=D4=D7=CF =CE=C5=D7=C5=CC=C9=CB=CF, =DC=D4=CF =CE=C5 =
=C2=D5=C4=C5=D4 =D3=D4=CF=C9=D4=D8, =DE=D4=CF =CE=C1=CD=CE=CF=C7=CF =C2=CF=
=CC=D8=DB=C5, =DE=D4=CF=C2=D9
=D0=CF=CC=D5=DE=C9=D4=D8 =D0=CF=CC=D8=DA=CF=D7=C1=D4=C5=CC=D8=D3=CB=C9=C5 =
=C2=D5=C8=D4=C1=C8 =D3 =F7=C1=DB=C9=CD=C9 =D4=D2=C5=C2=CF=D7=C1=CE=C9=D1=CD=
=C9.
Reply by Jim Thompson●May 24, 20132013-05-24
On Fri, 24 May 2013 09:46:04 -0700, Joerg <invalid@invalid.invalid>
wrote:
I thought it was a very poignant comment ;-)
...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
On Sun, 05 May 2013 19:57:27 -0500, Vladimir Vassilevsky
<nospam@nowhere.com> wrote:
>
>I have to make low power SMPS operable up to several hundred volts. For=20
>obvious reasons, it would be good to use off the shelf SMT inductors.
>In datasheets, they always specify inductor max. current, however they=20
>don't say anything about max. voltage.
>
>Any advice or relevant experience?
>
>Vladimir Vassilevsky
>DSP and Mixed Signal Designs
>www.abvolt.com
Not so much as experience, but some relatively sound advice.
Wire insulation withstand comes in voltage ratings, like low voltage 50 V
or less, 300 V or less, 600 V or less, 1000 V or less. Select for
insulation voltage rating to suit your needs. =20
See NFPA 70 "National Electrical Code" and=20
ANSI/IEEE C2 "National Electrical Safety Code".
It also comes in temperature grades which are related to the hottest part
of the winding. That location varies a bit due to winding dimensions and
core losses with attendant core temperature rise.
See:
http://en.wikipedia.org/wiki/Insulation_system
?-)
Reply by Robert Macy●May 8, 20132013-05-08
On May 7, 6:56=A0pm, legg <l...@nospam.magma.ca> wrote:
> On Sun, 05 May 2013 19:57:27 -0500, Vladimir Vassilevsky
>
> <nos...@nowhere.com> wrote:
>
> >I have to make low power SMPS operable up to several hundred volts. For
> >obvious reasons, it would be good to use off the shelf SMT inductors.
> >In datasheets, they always specify inductor max. current, however they
> >don't say anything about max. voltage.
>
> >Any advice or relevant experience?
>
> >Vladimir Vassilevsky
> >DSP and Mixed Signal Designs
> >www.abvolt.com
>
> At higher voltages you'll find that core loss becomes a more serious
> factor in rise, as you're tempted to minimize turns and allow
> increased ripple current.
>
> Inductors can be used in series, if off-the-shelf parts look a little
> fragile, construction-wise.
>
> Deconstruct a few and eyeball internal layer and winding/core stress,
> if in doubt.
>
> RL
Be aware when using heat dissipating devices in series that a lot of
that heat is intended to leave via the end terminations. Which means
the end attached to another will not be losing heat as fast as you
thought. Two in series we used to dreate a bit something like to 70%
of what you can do with one. And for three in series, well the center
one is going to get the hottest. To mitigate a bit, we'd use oversized
metal pours around the connections. Helped a bit.
Reply by legg●May 7, 20132013-05-07
On Sun, 05 May 2013 19:57:27 -0500, Vladimir Vassilevsky
<nospam@nowhere.com> wrote:
>
>I have to make low power SMPS operable up to several hundred volts. For
>obvious reasons, it would be good to use off the shelf SMT inductors.
>In datasheets, they always specify inductor max. current, however they
>don't say anything about max. voltage.
>
>Any advice or relevant experience?
>
>Vladimir Vassilevsky
>DSP and Mixed Signal Designs
>www.abvolt.com
At higher voltages you'll find that core loss becomes a more serious
factor in rise, as you're tempted to minimize turns and allow
increased ripple current.
Inductors can be used in series, if off-the-shelf parts look a little
fragile, construction-wise.
Deconstruct a few and eyeball internal layer and winding/core stress,
if in doubt.
RL
Reply by Joerg●May 7, 20132013-05-07
Robert Baer wrote:
> Vladimir Vassilevsky wrote:
>>
>> I have to make low power SMPS operable up to several hundred volts. For
>> obvious reasons, it would be good to use off the shelf SMT inductors.
>> In datasheets, they always specify inductor max. current, however they
>> don't say anything about max. voltage.
>>
>> Any advice or relevant experience?
>>
>> Vladimir Vassilevsky
>> DSP and Mixed Signal Designs
>> www.abvolt.com
> Any inductor can have a voltage rating; that depends on the wire
> insulation (lacquer, beldasol, etc) and should be less that the volts
> per turn mitigated by how many turns from one wire to physically next wire.
> At high frequencies, it is prolly reduced a lot.
>
As a teenager I found that out the hard way with an RF power amp design,
tubes. BIG tubes. Used it at higher frequencies, worked, yeehaw! Then
... tzzt ... pop .. pop-pop ... PHSSSST ... *PHOOOF* ... plate current
meter briefly pegged ... thwock .. all lights out. It had tripped the
mains breaker.
After disecting it turned out that the plate choke had completely
clumped and welded together, leaving spatters all around it. An amperage
smell wafted through the house.
--
Regards, Joerg
http://www.analogconsultants.com/
Reply by Joerg●May 7, 20132013-05-07
Klaus Kragelund wrote:
> On Monday, May 6, 2013 2:57:27 AM UTC+2, Vladimir Vassilevsky wrote:
>> I have to make low power SMPS operable up to several hundred volts.
>> For
>>
>> obvious reasons, it would be good to use off the shelf SMT
>> inductors.
>>
>> In datasheets, they always specify inductor max. current, however
>> they
>>
>> don't say anything about max. voltage.
>>
>>
>> Any advice or relevant experience?
>>
>
> I have used the Bourns SDR0805 for a 15V buck converter with 400VDC
> input. Upon request, the manufactor has stated that the inductor is
> good for 600VDC
>
That is the correct way to do it with such high voltages. Ask the
manufacturer for a statement, preferably in writing. Anything else would
IMHO be irresponsible when doing a product design.
> http://www.bourns.com/pdfs/SDR0805.pdf
>
> AFAIR, at these voltages you need to be carefull that you will not
> get corona discharge effects, but at least we didn't see any during
> the testing.
>
It can become a concern if used in other climate zones. Sometimes
coating or potting can help.
--
Regards, Joerg
http://www.analogconsultants.com/
Reply by Klaus Kragelund●May 7, 20132013-05-07
On Monday, May 6, 2013 2:57:27 AM UTC+2, Vladimir Vassilevsky wrote:
> I have to make low power SMPS operable up to several hundred volts. For
>
> obvious reasons, it would be good to use off the shelf SMT inductors.
>
> In datasheets, they always specify inductor max. current, however they
>
> don't say anything about max. voltage.
>
>
> Any advice or relevant experience?
>
I have used the Bourns SDR0805 for a 15V buck converter with 400VDC input. Upon request, the manufactor has stated that the inductor is good for 600VDC
http://www.bourns.com/pdfs/SDR0805.pdf
AFAIR, at these voltages you need to be carefull that you will not get corona discharge effects, but at least we didn't see any during the testing.
Cheers
Klaus