Driver to drive?

Paul Hovnanian P.E. wrote:

Winfield Hill wrote:

Paul Hovnanian P.E. wrote...

[ snip]
Read it and weep. I struggled with this stupidity 25 years ago with my
company's exports, but then it was merely a painful inconvenience, with
a financial hit against me. Now it's a financial suicide for our country.


If the US military establishment is smart and they want to keep
sensitive technology here at home, they need their own engineering and
manufacturing capability. That would solve a lot of their contracting
problems with missles as well.
Click to expand...
Not that this stuff is really that advanced. We'd be able too
if we were paid for it. Instead we have to connect three transistors
to inflate a toy ballon to cover the expenses for our living.

Rene
--
Ing.Buero R.Tschaggelar - http://www.ibrtses.com
& commercial newsgroups - http://www.talkto.net
 
Hi Mark,

For a brief but concise summary see Atmel's app note AVR450. It's about
a uC based charger but explains charging methods of the different
chemistry batteries.

Be careful since Li Ion batteries can explode when mistreated. As far as
I know it is not a good idea to charge in a series configuration.

Regards, Joerg

http://www.analogconsultants.com
 
Mark Jones <abuse@127.0.0.1> wrote:
Hi. I'm looking at the LM3622 datasheet
(http://www.national.com/ds/LM/LM3622.pdf). It's a simple Li-ion
linear charger. Comes in 4v/8v Li-ion versions. In Li-ion topology, a
lot of fuss is made about the cell's final voltage accuracy and how
overshooting this will destroy the cell. But what would happen if two
cells in series were chargeed with one unequally depleted? Wouldn't
the other cell shoot way over its rated voltage, destroying it? It
Click to expand...
Yes.
There are various ways to get round this.
For example, when on discharge you detect an imabalance, you connect
a small load to the unbalanced cell.
Or, do the same on charge, to shunt some of the charge current away.
 
Pooh Bear wrote:

John Larkin wrote:


Some guys I sometime work with messed up a couple of years ago, and
shipped a NIM module to the wrong party in India. They were raided by
big guys in flak jackets with automatic weapons, arrested, and
criminally indicted. They wound up not doing time, eventually, but the
fines and legal fees easily exceeded $500K.


Sounds totally OTT. But what's a NIM module anyway ?
Click to expand...
NIM was the standard for the accelerator and nuclear guys.
It covered signals, power supplies and cases.
The term NIM was alone worth a 100% increase.

Rene
--
Ing.Buero R.Tschaggelar - http://www.ibrtses.com
& commercial newsgroups - http://www.talkto.net
 
Stratcat wrote:

Hi guys -

First time posting here.

I'm doing some PC overclocking & have been finding my cpu pwr FETs are
really sizzlin'! I don't have the equipment to get a temp reading, but
several ppl on an overclocking forum I'm a member of, have already lost some
motherboards due to blowing a FET. We're overclocking 1st generation Intel
P4 Prescott cpu's, and they extremely power hungry. Some peeps have resorted
to adding heat sinks to their FETs, with varying success.

I don't have the PN or datasheet handy; Sorry. They're 3P (S-G-D)
power MOSFETS w/a high impedance gate.

I was wondering: Since the gate is a very high impedance, can MOSFETs
be 'paralleled up' if they are identical components? IOW, I'm considering
simply soldering an identical FET to the legs of the original FETs, in a
pin-to-pin manner. This would be an attempt to loadshare using additional
FETs.

It would seem to me the only concern would be if the device driving the
gates can provide enough gate current for the original & additional FET,
in each instance.

Anyone have any opinions???
Click to expand...
Doubling up mosfets will present double the gate capacitance to the driver chip
which may actually cause more problems ! The two devices will be close together
so you'll get 'thermal masking' that won't actually reduce the operational temp
that much.

A decent heatsink is simple and effective. It need not be large or require a
fan. Any transistor ( including mosfets ) can only safely dissipate a fraction
of its potential capability without one.

If there's room around the device a simple 'clip on' heatsink may do the job.

Graham
 
Joel Kolstad wrote:

"Chris Carlen" <crcarle@BOGUS.sandia.gov> wrote in message
news:coi3q501rk5@news3.newsguy.com...
JW Magnetics has confirmed they are for EMI.

What I've learned from your story here is that one shouldn't expect to use a
given inductor in an AC application unless the manufacturer gives you a
hysteresis loss curve!
Click to expand...
Micrometals www.micrometals.com have a nice little free downloadable application
that works out those losses and then presents you with various options you can
wind on their cores. You can trade DC R - power losses etc.


Graham
 
Joerg wrote:

Hi Mark,

For a brief but concise summary see Atmel's app note AVR450. It's about
a uC based charger but explains charging methods of the different
chemistry batteries.

Be careful since Li Ion batteries can explode when mistreated. As far as
I know it is not a good idea to charge in a series configuration.

Regards, Joerg

http://www.analogconsultants.com
Click to expand...
Li-Ion batteries have been taken up by the electric-powered model
airplane crowd, because of their good energy density characteristics.
They are usually pushed _hard_; discharged fast, charged in series, etc.

So now there's a little ceramic vault you can buy to charge and store
your Li-Ion e-flight batteries in, to contain the fire...

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
 
Hi Dmitri,

As for databases, your PC most likely already has one. MS-Works contains a database. I use it for most everything. But first you have to learn it (well worth the time) and then take a piece of paper and decide on a sorting and categorizing scheme.

It makes sense to label every location where you store parts, detailed anough so you can avoid unloading a whole shelf to find that lone edge connector or a BNC plug.

I bet that after learning how to use that or another database you'll see how to organize other stuff as well.

Regards, Joerg

http://www.analogconsultants.com
 
Pooh Bear wrote:
Careful. Ferrites saturate rapidly. You might need an air gap.

Check out Epcos's Ferrite magnetic design tool ( downloadable from epcos.com
).

It does all the calculations for you. You want the DC bias tab btw.


Graham
Click to expand...

Where is "epcos.com" anyway?

I vaguely recall attempting that URL a long time ago and also came up
with nothing.


Oh, here's a link, from Eastern Components:

http://www.eastern-components.com/designtool.htm


Good day!



--
_______________________________________________________________________
Christopher R. Carlen
Principal Laser/Optical Technologist
Sandia National Laboratories CA USA
crcarle@sandia.gov -- NOTE: Remove "BOGUS" from email address to reply.
 
Terry Given <my_name@ieee.org> wrote in message news:<HsSqd.18684$9A.310493@news.xtra.co.nz>...
John Popelish wrote:

Yep. A good data sheet is much better than an assumption:
http://www.irctt.com/pdf_files/HSF.pdf


Wow, thats GREAT! pisses all over the CHP series!

I'll remember that part, thanks John.
Click to expand...
Now, find me someone who stocks them.
 
On Tue, 30 Nov 2004 08:22:59 +0000, Paul Burke wrote:

Terry Given wrote:

They seemed to accept my "crippled, deformed and retarded people" for my
target market. Next time I might try "stupid paranoid people" or perhaps
"lesbian amputees". Sex toys of course make for great product
descriptions, as does anything medical - colostomy bag sterilisers
anyone?

Apart from your choice being a wee bit less than PC, that's a wonderful
idea. I know that many years ago when I'd pulled a sickie, I signed off
the self- certification saying I'd been suffering from hyperdulia. No one
in the office was interested enough to look it up in the dictionary, so I
got away with it.
Click to expand...
Ah! Vererable Disease!

;-)
Rich
 
Frank Bemelman wrote:
Dear Mr. Bemelmann,

Thank you for your interest in Digi-Key. Because of the export law of
the USA you answered 5 export questions. We have 2 little questions
about that.

One is about the specific application because you wrote "hobby kits".
Please describe it cleanlier or please send us more information about
that. (for example some examples).

The second request is about the end user. Please fill in at least the
target group.

Thank you.

After we received your information about that we will transfer it to our
head office which will send your order.

Thank you.
Kind regards,
Kerstin Langer

Tel.: 0800-020-3710
Fax: 0031-53-484-9583
nl.digikey.com <http://www.digikey.com/
----------------------------------

Dear Kirsten,

While you probably have no other choice than to conform
to these these silly laws, I have no intention to change
my views on the latest policies of your deluded government.

That leaves you two options, ship the merchandise or cancel the
order.

I am not going to comply with any further spanish inquisition.

Best regards,
Frank Bemelman
Click to expand...

My Mom used to call this, "cutting off one's ones to spite one's face."

Do I want my parts??? Can I bring myself to comply with some silly
regulation that doesn't make a bit of difference???

Nope, I think I'll be proud and sulk...and maybe whimper my folly to the
largest audience I can find.

It's hard to muster up sympathy...
Better get a bicycle, 'cause they're gonna ask you for your address next
time you renew your driver's license. Ohmygod, they're gonna ask you to
prove that you can see well enough to drive. Can't let them do that!!!
Here in the USA, they even take your picture. What right do they have
to do that???

Sigh,
mike

--
Return address is VALID.
500MHz Tek DSOscilloscope TDS540 $2200
http://nm7u.tripod.com/homepage/te.html
Wanted, 12.1" LCD for Gateway Solo 5300. Samsung LT121SU-121
Bunch of stuff For Sale and Wanted at the link below.
http://www.geocities.com/SiliconValley/Monitor/4710/
 
On Mon, 15 Nov 2004 14:26:52 +0200, Phil Carmody wrote:

Michael Mendelsohn <keine.Werbung.1300@msgid.michael.mendelsohn.de
writes:

Nick Wedd schrieb:
Given that Portugal's border with Spain is 23% longer than Spain's
border with Portugal, it would be interesting to see the actual
figures.

Is that because maps of Portugal are at a different scale than maps of
Spain?

Anything's possible when it comes to the CIA world factbook:

http://fatphil.org/errors/american_metric.jpg

Phil
Click to expand...
Cheers!
Rich
 
JeffM wrote...
when this stuff was invented

Yup. Stroger Switches were invented in 1884--by an undertaker.
Click to expand...
Do you think they used -48V back then?


--
Thanks,
- Win
 
On Tue, 30 Nov 2004 13:26:06 -0800, mike wrote:

My Mom used to call this, "cutting off one's ones to spite one's face."
^^^^
Click to expand...
stereo dyslexia?


Bob
 
Bob Stephens wrote:
On Tue, 30 Nov 2004 13:26:06 -0800, mike wrote:


My Mom used to call this, "cutting off one's ones to spite one's face."

^^^^
stereo dyslexia?


Bob
Click to expand...
Yes, my Mom was dyslexic ;-)
mike

--
Return address is VALID.
500MHz Tek DSOscilloscope TDS540 $2200
http://nm7u.tripod.com/homepage/te.html
Wanted, 12.1" LCD for Gateway Solo 5300. Samsung LT121SU-121
Bunch of stuff For Sale and Wanted at the link below.
http://www.geocities.com/SiliconValley/Monitor/4710/
 
On Tue, 30 Nov 2004 13:26:06 -0800, mike <spamme0@netscape.net> wrote:

Frank Bemelman wrote:
Dear Mr. Bemelmann,

Thank you for your interest in Digi-Key. Because of the export law of
the USA you answered 5 export questions. We have 2 little questions
about that.

One is about the specific application because you wrote "hobby kits".
Please describe it cleanlier or please send us more information about
that. (for example some examples).

The second request is about the end user. Please fill in at least the
target group.

Thank you.

After we received your information about that we will transfer it to our
head office which will send your order.

Thank you.
Kind regards,
Kerstin Langer

Tel.: 0800-020-3710
Fax: 0031-53-484-9583
nl.digikey.com <http://www.digikey.com/
----------------------------------

Dear Kirsten,

While you probably have no other choice than to conform
to these these silly laws, I have no intention to change
my views on the latest policies of your deluded government.

That leaves you two options, ship the merchandise or cancel the
order.

I am not going to comply with any further spanish inquisition.

Best regards,
Frank Bemelman


My Mom used to call this, "cutting off one's ones to spite one's face."

Do I want my parts??? Can I bring myself to comply with some silly
regulation that doesn't make a bit of difference???

Nope, I think I'll be proud and sulk...and maybe whimper my folly to the
largest audience I can find.

It's hard to muster up sympathy...
Better get a bicycle, 'cause they're gonna ask you for your address next
time you renew your driver's license. Ohmygod, they're gonna ask you to
prove that you can see well enough to drive. Can't let them do that!!!
Here in the USA, they even take your picture. What right do they have
to do that???

Sigh,
mike
Click to expand...
It's Bemelman, what else can you say ?:)

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.
 
Hi Rene,

As to the file, I made a webpage (not to be released) where
I can view the list of parts, with links to the sorted datasheets.
Click to expand...

Interesting. Can that web page sort? For example, if you wanted to know
which different types of Schmitt trigger chips you have on hand, or what
kinds of FETs in SOT23 package, could it list that for you?

Regards, Joerg

http://www.analogconsultants.com
 
In article <41ABC899.FCADF295@Hovnanian.com>,
Paul Hovnanian P.E. <Paul@Hovnanian.com> wrote:
[...]
That's why companies like Boeing are pushing all their engineering and
s/w development offshore. If you want to export something to a
particular country, you've got to jump through all the hoops. If one of
your partners (wholly owned, of course) in China, India or Russia
develops it, the restrictions are less onerous.
Click to expand...
Also:

If you are a Canadian (or Brit etc) company and you want to ship something
to China, you can get your license in short amount of time. (Assuming
there isn't a reason you can't) If you are a US firm, the paper work
disappears into a black hole for several months. If the customer is in a
hurry you lose the sale.


It is amazing how a bad system can make smart people do things so dumb.
--
--
kensmith@rahul.net forging knowledge
 
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