One of the ports of my NEC-based USB 2.0 card quit working because the
National Semiconductor LM3526 power controller chip failed. I'm
pretty sure that I didn't zap it with static (I always touch the
outher metal shell to the computer case before plugging it in) or try
to plug it in backwards. The data sheet for the LM3526 says that it's
protected against voltage, current, and even temperature, so what
happened?

National Semiconductor says that each USB port must have a 120uF or
larger tantalum capacitor between +5V and ground for protection
against transients that occur during hot-plugging, and NEC's example
schematic for their uPD720100A USB 2.0 chip shows the LM3526 using
150uF aluminum in parallel with 0.1uF ceramic. But my USB card has
only a 100uF aluminum capacitor and maybe a ceramic capacitor in
parallel for this. Could this be why the USB port got zapped? Would
it help to solder a tantalum in parallel as well? Will it hurt to add
it?

"larrymoencurly" wrote in message
om...
....
| National Semiconductor says that each USB port must have a 120uF or
| larger ....................................... But my USB card has
| only a 100uF aluminum capacitor and maybe a ceramic capacitor in
| parallel for this....

Close enough!

N

On Mon, 04 Oct 2004 01:50:54 GMT, "NSM" wrote:


"larrymoencurly" wrote in message
. com...
...
| National Semiconductor says that each USB port must have a 120uF or
| larger ....................................... But my USB card has
| only a 100uF aluminum capacitor and maybe a ceramic capacitor in
| parallel for this....

Close enough!

Except the tantalum cap would have much lower esl & esr figures than an
aluminum cap, making it more effective.

otoh, tantalums can have a brilliant failure mode ;-)

"larrymoencurly" wrote in message
om...
One of the ports of my NEC-based USB 2.0 card quit working because the
National Semiconductor LM3526 power controller chip failed. I'm
pretty sure that I didn't zap it with static (I always touch the
outher metal shell to the computer case before plugging it in) or try
to plug it in backwards. The data sheet for the LM3526 says that it's
protected against voltage, current, and even temperature, so what
happened?


Stuff just fails occasionally with no good explaination, could be it was
just a defective part that eventually quit.

"James Sweet" wrote in message
news:lu58d.2427$r3.597@trnddc05...
|
| "larrymoencurly" wrote in message
| om...
| One of the ports of my NEC-based USB 2.0 card quit working because the
| National Semiconductor LM3526 power controller chip failed. I'm
| pretty sure that I didn't zap it with static (I always touch the
| outher metal shell to the computer case before plugging it in) or try
| to plug it in backwards. The data sheet for the LM3526 says that it's
| protected against voltage, current, and even temperature, so what
| happened?
|
|
| Stuff just fails occasionally with no good explaination, could be it was
| just a defective part that eventually quit.

Or as I say, "Everything works until it breaks". Then there are the three
brand new tubes I took off the shelf one at a time, each of which was bad.
Still can't get over that one.

N

NSM wrote:

"James Sweet" wrote in message
news:lu58d.2427$r3.597@trnddc05...
|
| "larrymoencurly" wrote in message
| om...
| One of the ports of my NEC-based USB 2.0 card quit working because the
| National Semiconductor LM3526 power controller chip failed. I'm
| pretty sure that I didn't zap it with static (I always touch the
| outher metal shell to the computer case before plugging it in) or try
| to plug it in backwards. The data sheet for the LM3526 says that it's
| protected against voltage, current, and even temperature, so what
| happened?
|
|
| Stuff just fails occasionally with no good explaination, could be it was
| just a defective part that eventually quit.

Or as I say, "Everything works until it breaks".

HEY!! That's MY line.

Then there are the three
brand new tubes I took off the shelf one at a time, each of which was bad.
Still can't get over that one.

Find the guy who put the defective ones back on the shelf g.


N

"James Sweet" wrote in message news:lu58d.2427$r3.597@trnddc05...

Stuff just fails occasionally with no good explaination, could be
it was just a defective part that eventually quit.

I am eternally grateful for your answer, which not only completely
solved my problem with the USB port but will also magically turn the
rest of my life into bliss. So please give me your address so that I
can send you a $500 check, no, make that a blank check -- your advice
was that good.

On 4 Oct 2004 13:57:43 -0700,
(larrymoencurly) wrote:

"James Sweet" wrote in message news:lu58d.2427$r3.597@trnddc05...

Stuff just fails occasionally with no good explaination, could be
it was just a defective part that eventually quit.

I am eternally grateful for your answer, which not only completely
solved my problem with the USB port but will also magically turn the
rest of my life into bliss. So please give me your address so that I
can send you a $500 check, no, make that a blank check -- your advice
was that good.

Believe it or not, it was a good and reasonable response, given the
information he had to work with.

Tom

On Mon, 04 Oct 2004 03:21:58 +0000, daytripper wrote:

On Mon, 04 Oct 2004 01:50:54 GMT, "NSM" wrote:


"larrymoencurly" wrote in message
.com...
...
| National Semiconductor says that each USB port must have a 120uF or
| larger ....................................... But my USB card has
| only a 100uF aluminum capacitor and maybe a ceramic capacitor in
| parallel for this....

Close enough!

Except the tantalum cap would have much lower esl & esr figures than an
aluminum cap, making it more effective.

otoh, tantalums can have a brilliant failure mode ;-)

So do engineers when they're bringing up a system where all
of the tantallums were inserted backwards. You want to see fireworks!
(well,it was 25 years ago - I've mostly recovered and the tinninus
isn't so bad. twitch)

--
Keith

keith wrote:

On Mon, 04 Oct 2004 03:21:58 +0000, daytripper wrote:


On Mon, 04 Oct 2004 01:50:54 GMT, "NSM" wrote:


"larrymoencurly" wrote in message
e.com...
...
| National Semiconductor says that each USB port must have a 120uF or
| larger ....................................... But my USB card has
| only a 100uF aluminum capacitor and maybe a ceramic capacitor in
| parallel for this....

Close enough!

Except the tantalum cap would have much lower esl & esr figures than an
aluminum cap, making it more effective.

otoh, tantalums can have a brilliant failure mode ;-)


So do engineers when they're bringing up a system where all
of the tantallums were inserted backwards. You want to see fireworks!
(well,it was 25 years ago - I've mostly recovered and the tinninus
isn't so bad. twitch)


LOL. Yeah, I'll bet.

You get a similar result plugging non keyed circuit boards into a vertical
card rack 180 degrees reversed.

"keith" wrote in message
news
| So do engineers when they're bringing up a system where all
| of the tantallums were inserted backwards. You want to see fireworks!
| (well,it was 25 years ago - I've mostly recovered and the tinninus
| isn't so bad. twitch)

I recall being told of a large TTL circuit board which was powered up with
reverse polarity. This was noticed due to the considerable amount of heat
being given off.

Everyone was mystified when the correctly rewired board worked OK. I guess
TTL is a little more tolerant than is generally believed.

N

forgive me for not immediately recommending you open the controller chip and
place it under your scanning electron microscope to search for signs of
electromigration...


"larrymoencurly" wrote in message
om...
"James Sweet" wrote in message
news:lu58d.2427$r3.597@trnddc05...

Stuff just fails occasionally with no good explaination, could be
it was just a defective part that eventually quit.

I am eternally grateful for your answer, which not only completely
solved my problem with the USB port but will also magically turn the
rest of my life into bliss. So please give me your address so that I
can send you a $500 check, no, make that a blank check -- your advice
was that good.

"larrymoencurly" wrote in message
om...
"James Sweet" wrote in message
news:lu58d.2427$r3.597@trnddc05...

Stuff just fails occasionally with no good explaination, could be
it was just a defective part that eventually quit.

I am eternally grateful for your answer, which not only completely
solved my problem with the USB port but will also magically turn the
rest of my life into bliss. So please give me your address so that I
can send you a $500 check, no, make that a blank check -- your advice
was that good.


Just what sort of answer did you expect? I seem to have misplaced my crystal
ball and I can't find my spell book either. How is anyone supposed to tell
you why a chip failed? It just happens.

"larrymoencurly" wrote in message
om...
| "James Sweet" wrote in message
news:lu58d.2427$r3.597@trnddc05...
|
| Stuff just fails occasionally with no good explaination, could be
| it was just a defective part that eventually quit.
|
| I am eternally grateful for your answer, which not only completely
| solved my problem with the USB port but will also magically turn the
| rest of my life into bliss. So please give me your address so that I
| can send you a $500 check, no, make that a blank check -- your advice
| was that good.

Assuming you are being sarcastic (it's not clear), I refer to this as a
CatRan question, i.e., "I was typing away on my computer and I was holding
the keyboard above my head and I was watching the screen through my toes
when all of a sudden the cat ran over my stomach and I noticed the screen
blinked twice. What causes that"?

N

On Mon, 04 Oct 2004 22:33:31 -0500, David Maynard wrote:

keith wrote:

On Mon, 04 Oct 2004 03:21:58 +0000, daytripper wrote:


On Mon, 04 Oct 2004 01:50:54 GMT, "NSM" wrote:


"larrymoencurly" wrote in message
le.com...
...
| National Semiconductor says that each USB port must have a 120uF or
| larger ....................................... But my USB card has
| only a 100uF aluminum capacitor and maybe a ceramic capacitor in
| parallel for this....

Close enough!

Except the tantalum cap would have much lower esl & esr figures than an
aluminum cap, making it more effective.

otoh, tantalums can have a brilliant failure mode ;-)


So do engineers when they're bringing up a system where all
of the tantallums were inserted backwards. You want to see fireworks!
(well,it was 25 years ago - I've mostly recovered and the tinninus
isn't so bad. twitch)


LOL. Yeah, I'll bet.

You get a similar result plugging non keyed circuit boards into a vertical
card rack 180 degrees reversed.

A good reason to hang the mechanical designers by the short things. One
*should* have to go to great lengths to pluch dangerous things in
backwards. In this case they did just that. ...and even complained about
how hard it was!

--
Keith

On Tue, 05 Oct 2004 03:47:13 +0000, NSM wrote:


"keith" wrote in message
news
| So do engineers when they're bringing up a system where all
| of the tantallums were inserted backwards. You want to see fireworks!
| (well,it was 25 years ago - I've mostly recovered and the tinninus
| isn't so bad. twitch)

I recall being told of a large TTL circuit board which was powered up with
reverse polarity. This was noticed due to the considerable amount of heat
being given off.

Everyone was mystified when the correctly rewired board worked OK. I guess
TTL is a little more tolerant than is generally believed.

TTL protection diodes are as strong as moose! Unless the chips got hot
enough to let the magic smoke out, they'll likely survive, though perhaps
somewhat injured.

--
Keith

keith wrote:

On Mon, 04 Oct 2004 22:33:31 -0500, David Maynard wrote:


keith wrote:


On Mon, 04 Oct 2004 03:21:58 +0000, daytripper wrote:



On Mon, 04 Oct 2004 01:50:54 GMT, "NSM" wrote:



"larrymoencurly" wrote in message
gle.com...
...
| National Semiconductor says that each USB port must have a 120uF or
| larger ....................................... But my USB card has
| only a 100uF aluminum capacitor and maybe a ceramic capacitor in
| parallel for this....

Close enough!

Except the tantalum cap would have much lower esl & esr figures than an
aluminum cap, making it more effective.

otoh, tantalums can have a brilliant failure mode ;-)


So do engineers when they're bringing up a system where all
of the tantallums were inserted backwards. You want to see fireworks!
(well,it was 25 years ago - I've mostly recovered and the tinninus
isn't so bad. twitch)


LOL. Yeah, I'll bet.

You get a similar result plugging non keyed circuit boards into a vertical
card rack 180 degrees reversed.


A good reason to hang the mechanical designers by the short things. One
*should* have to go to great lengths to pluch dangerous things in
backwards. In this case they did just that. ...and even complained about
how hard it was!


Hehe. Well, with the one I mentioned it was an experimental prototype built
by the design engineer.

"NSM" wrote in news:sgI8d.14605$MV5.538@clgrps13:


"larrymoencurly" wrote in message
om...
| "James Sweet" wrote in message
news:lu58d.2427$r3.597@trnddc05...
|
| Stuff just fails occasionally with no good explaination, could be
| it was just a defective part that eventually quit.
|
| I am eternally grateful for your answer, which not only completely
| solved my problem with the USB port but will also magically turn the
| rest of my life into bliss. So please give me your address so that I
| can send you a $500 check, no, make that a blank check -- your advice
| was that good.

Assuming you are being sarcastic (it's not clear), I refer to this as a
CatRan question, i.e., "I was typing away on my computer and I was
holding the keyboard above my head and I was watching the screen through
my toes when all of a sudden the cat ran over my stomach and I noticed
the screen blinked twice. What causes that"?

N




Reminds me of the time an aquaintance went to lunch with me and a few of
the other engineers. He was in a rather "know it all" mood. I started
plying him with questions about how water softeners work, what causes
gravity, etc. He was doing good until I asked him, "Ever wake up on a
wednesday and think it was tuesday all day and then wake up the next day
and everything is ok again? What is that called?" He shut up after that.

r

--
Nothing beats the bandwidth of a station wagon filled with DLT tapes.

Kibo informs me that keith stated that:

On Tue, 05 Oct 2004 03:47:13 +0000, NSM wrote:
"keith" wrote in message
news
| So do engineers when they're bringing up a system where all
| of the tantallums were inserted backwards. You want to see fireworks!
| (well,it was 25 years ago - I've mostly recovered and the tinninus
| isn't so bad. twitch)

grin They don't smell too good either.

I recall being told of a large TTL circuit board which was powered up with
reverse polarity. This was noticed due to the considerable amount of heat
being given off.

Everyone was mystified when the correctly rewired board worked OK. I guess
TTL is a little more tolerant than is generally believed.

TTL protection diodes are as strong as moose!

Well, the individual diodes aren't all that strong, but there's one on
every single I/O pin on every chip, so on a big PCB, the load will be
spread over a *lot* of diodes.

Unless the chips got hot
enough to let the magic smoke out, they'll likely survive, though perhaps
somewhat injured.

Yup. The best I've personally seen was the time I accidentally plugged a
2716 EPROM backwards into a programmer. It lit up like a xmas tree
through the UV window, but worked fine when I turned it around the right
way.

--
W
. | ,. w , "Some people are alive only because
\|/ \|/ it is illegal to kill them." Perna condita delenda est
---^----^---------------------------------------------------------------

Rich.Andrews wrote:

Reminds me of the time an aquaintance went to lunch with me and a
few of the other engineers. He was in a rather "know it all"
mood. I started plying him with questions about how water
softeners work, what causes gravity, etc. He was doing good
until I asked him, "Ever wake up on a wednesday and think it was
tuesday all day and then wake up the next day and everything is
ok again? What is that called?" He shut up after that.

Groundhog day?

"Rich.Andrews" wrote in message .1...

Assuming you are being sarcastic (it's not clear),

The "" always means non-hostile sarcasm.

I refer to this as a CatRan question, i.e., "I was typing away
on my computer and I was holding the keyboard above my head and
I was watching the screen through my toes when all of a sudden
the cat ran over my stomach and I noticed the screen blinked
twice. What causes that"?

I think that it's more like, why did the waterproof flashlight
suddenly stop working when it started to rain?

On Tue, 05 Oct 2004 23:09:32 -0500, David Maynard wrote:

keith wrote:

On Mon, 04 Oct 2004 22:33:31 -0500, David Maynard wrote:


keith wrote:


On Mon, 04 Oct 2004 03:21:58 +0000, daytripper wrote:



On Mon, 04 Oct 2004 01:50:54 GMT, "NSM" wrote:



"larrymoencurly" wrote in message
ogle.com...
...
| National Semiconductor says that each USB port must have a 120uF or
| larger ....................................... But my USB card has
| only a 100uF aluminum capacitor and maybe a ceramic capacitor in
| parallel for this....

Close enough!

Except the tantalum cap would have much lower esl & esr figures than an
aluminum cap, making it more effective.

otoh, tantalums can have a brilliant failure mode ;-)


So do engineers when they're bringing up a system where all
of the tantallums were inserted backwards. You want to see fireworks!
(well,it was 25 years ago - I've mostly recovered and the tinninus
isn't so bad. twitch)


LOL. Yeah, I'll bet.

You get a similar result plugging non keyed circuit boards into a vertical
card rack 180 degrees reversed.


A good reason to hang the mechanical designers by the short things. One
*should* have to go to great lengths to pluch dangerous things in
backwards. In this case they did just that. ...and even complained about
how hard it was!


Hehe. Well, with the one I mentioned it was an experimental prototype built
by the design engineer.

....even this design engineer knows how to key a connector. ;-)

--
Keith

On Wed, 06 Oct 2004 15:56:56 +1000, Lionel wrote:

Kibo informs me that keith stated that:

On Tue, 05 Oct 2004 03:47:13 +0000, NSM wrote:
"keith" wrote in message
news
| So do engineers when they're bringing up a system where all
| of the tantallums were inserted backwards. You want to see fireworks!
| (well,it was 25 years ago - I've mostly recovered and the tinninus
| isn't so bad. twitch)

grin They don't smell too good either.

Hot electricity never smells good. ...ever notice that? ;-)

I recall being told of a large TTL circuit board which was powered up with
reverse polarity. This was noticed due to the considerable amount of heat
being given off.

Everyone was mystified when the correctly rewired board worked OK. I guess
TTL is a little more tolerant than is generally believed.

TTL protection diodes are as strong as moose!

Well, the individual diodes aren't all that strong, but there's one on
every single I/O pin on every chip, so on a big PCB, the load will be
spread over a *lot* of diodes.

I've pumped several amps though individual ones, but you're right with
thousands in parallel it's tough to smoke 'em. It *can* be done, but...

Unless the chips got hot
enough to let the magic smoke out, they'll likely survive, though
perhaps somewhat injured.

Yup. The best I've personally seen was the time I accidentally plugged a
2716 EPROM backwards into a programmer. It lit up like a xmas tree
through the UV window, but worked fine when I turned it around the right
way.

Oh, my! I've never done that. However...

One time back in the '60s (when I was a mere lad playing with electronics)
a friend and I were talking about these new-fangled LED thingys. He said
they were no big deal and had them for some time. He then took a
small-signal glass-encapsulated diode from his pile-o-parts, bent the
leads about 3/4" apart and grabbed it with long-nosed pliers. He then
shoved it into the mains outlet and sure enough it lit up, and quite
brightly too! He did make some comment about his reliability problems, or
some such. I just about PMP. ;-)

--
Keith

keith wrote:

On Tue, 05 Oct 2004 23:09:32 -0500, David Maynard wrote:


keith wrote:


On Mon, 04 Oct 2004 22:33:31 -0500, David Maynard wrote:



keith wrote:



On Mon, 04 Oct 2004 03:21:58 +0000, daytripper wrote:




On Mon, 04 Oct 2004 01:50:54 GMT, "NSM" wrote:




"larrymoencurly" wrote in message
oogle.com...
...
| National Semiconductor says that each USB port must have a 120uF or
| larger ....................................... But my USB card has
| only a 100uF aluminum capacitor and maybe a ceramic capacitor in
| parallel for this....

Close enough!

Except the tantalum cap would have much lower esl & esr figures than an
aluminum cap, making it more effective.

otoh, tantalums can have a brilliant failure mode ;-)


So do engineers when they're bringing up a system where all
of the tantallums were inserted backwards. You want to see fireworks!
(well,it was 25 years ago - I've mostly recovered and the tinninus
isn't so bad. twitch)


LOL. Yeah, I'll bet.

You get a similar result plugging non keyed circuit boards into a vertical
card rack 180 degrees reversed.


A good reason to hang the mechanical designers by the short things. One
*should* have to go to great lengths to pluch dangerous things in
backwards. In this case they did just that. ...and even complained about
how hard it was!


Hehe. Well, with the one I mentioned it was an experimental prototype built
by the design engineer.


...even this design engineer knows how to key a connector. ;-)


Hehe. I bet that one does too... NOW

keith wrote:

On Wed, 06 Oct 2004 15:56:56 +1000, Lionel wrote:


Kibo informs me that keith stated that:


On Tue, 05 Oct 2004 03:47:13 +0000, NSM wrote:

"keith" wrote in message
news
| So do engineers when they're bringing up a system where all
| of the tantallums were inserted backwards. You want to see fireworks!
| (well,it was 25 years ago - I've mostly recovered and the tinninus
| isn't so bad. twitch)

grin They don't smell too good either.


Hot electricity never smells good. ...ever notice that? ;-)


I recall being told of a large TTL circuit board which was powered up with
reverse polarity. This was noticed due to the considerable amount of heat
being given off.

Everyone was mystified when the correctly rewired board worked OK. I guess
TTL is a little more tolerant than is generally believed.

TTL protection diodes are as strong as moose!

Well, the individual diodes aren't all that strong, but there's one on
every single I/O pin on every chip, so on a big PCB, the load will be
spread over a *lot* of diodes.


I've pumped several amps though individual ones, but you're right with
thousands in parallel it's tough to smoke 'em. It *can* be done, but...

Unless the chips got hot
enough to let the magic smoke out, they'll likely survive, though
perhaps somewhat injured.

Yup. The best I've personally seen was the time I accidentally plugged a
2716 EPROM backwards into a programmer. It lit up like a xmas tree
through the UV window, but worked fine when I turned it around the right
way.


Oh, my! I've never done that. However...

One time back in the '60s (when I was a mere lad playing with electronics)
a friend and I were talking about these new-fangled LED thingys. He said
they were no big deal and had them for some time. He then took a
small-signal glass-encapsulated diode from his pile-o-parts, bent the
leads about 3/4" apart and grabbed it with long-nosed pliers. He then
shoved it into the mains outlet and sure enough it lit up, and quite
brightly too! He did make some comment about his reliability problems, or
some such. I just about PMP. ;-)


A bit on the high side with power consumption too, I'll wager. hehe

what main board? FIC ECS MSI?...usb blew cause the board blows.

"larrymoencurly" wrote in message
om...
One of the ports of my NEC-based USB 2.0 card quit working because
the
National Semiconductor LM3526 power controller chip failed. I'm
pretty sure that I didn't zap it with static (I always touch the
outher metal shell to the computer case before plugging it in) or
try
to plug it in backwards. The data sheet for the LM3526 says that
it's
protected against voltage, current, and even temperature, so what
happened?

National Semiconductor says that each USB port must have a 120uF or
larger tantalum capacitor between +5V and ground for protection
against transients that occur during hot-plugging, and NEC's example
schematic for their uPD720100A USB 2.0 chip shows the LM3526 using
150uF aluminum in parallel with 0.1uF ceramic. But my USB card has
only a 100uF aluminum capacitor and maybe a ceramic capacitor in
parallel for this. Could this be why the USB port got zapped?
Would
it help to solder a tantalum in parallel as well? Will it hurt to
add
it?

"JAD" wrote in message ...

"larrymoencurly" wrote in message
om...

One of the ports of my NEC-based USB 2.0 card quit working because
the National Semiconductor LM3526 power controller chip failed.
I'm pretty sure that I didn't zap it with static or try to plug
it in backwards. The data sheet for the LM3526 says that it's
protected against voltage, current, and even temperature, so what
happened?

National Semiconductor says that each USB port must have a 120uF or
larger tantalum capacitor between +5V and ground for protection
against transients that occur during hot-plugging, and NEC's
example
schematic for their uPD720100A USB 2.0 chip shows the LM3526 using
150uF aluminum in parallel with 0.1uF ceramic. But my USB card has
only a 100uF aluminum capacitor and maybe a ceramic capacitor in
parallel for this. Could this be why the USB port got zapped?
Would it help to solder a tantalum in parallel as well? Will it
hurt?

what main board? FIC ECS MSI?...usb blew cause the board blows.

My main boards are cheap, FIC and ECS, so any built-in USB for them
uses an SiS or VIA chip. My NEC USB is a PCI card. But why couldn't
any built-in USB blow out because of something off the main board? I
had a built-in RS-232 serial port blow because someone tried to hot
plug a parallel printer port (vaporized a couple of tiny capacitors
used by the RS-232-TTL converter chip), no other damage.

In comp.sys.ibm.pc.hardware.chips keith wrote:
glass-encapsulated diode from his pile-o-parts, bent the
leads about 3/4" apart and grabbed it with long-nosed pliers.
He then shoved it into the mains outlet and sure enough it lit
up, and quite brightly too! He did make some comment about
his reliability problems, or some such. I just about PMP. ;-)

Well, OK. But now traffic engineers are installing LED traffic
light replacement bulbs specifically _for_ reliability?

Daisy chain a dozen or so LEDs all facing one way, and plug it in.
Face another set the other way. Parallel as many as you need for
brightness. Nicely vibration resistant.

-- Robert

"JAD" top posted:

reliability and power consumption,,,,,,,,,,,,,,,,
speaking of street lights I was reading yesterday that a number a US
cities are being investigated about their manipulation of the traffic
signals to burn more gas, thus creating revenue for the city, (gas
city level taxes)

Right. And OJ isn't guilty.

huh?


he is guilty (whatever connection there is to that) and so are the
cities involved in the lighting scam......\ or are you saying that its
impossible? very naive...but it was a side note and not meant for
debate.


"chrisv" wrote in message
...
"JAD" top posted:

reliability and power consumption,,,,,,,,,,,,,,,,
speaking of street lights I was reading yesterday that a number a
US
cities are being investigated about their manipulation of the
traffic
signals to burn more gas, thus creating revenue for the city, (gas
city level taxes)

Right. And OJ isn't guilty.

keith wrote in
news
One time back in the '60s (when I was a mere lad playing with
electronics) a friend and I were talking about these new-fangled LED
thingys. He said they were no big deal and had them for some time. He
then took a small-signal glass-encapsulated diode from his
pile-o-parts, bent the leads about 3/4" apart and grabbed it with
long-nosed pliers. He then shoved it into the mains outlet and sure
enough it lit up, and quite brightly too!

I once had a bizarre failure of a USR modem immediately after a
thunderstorm. You would think it would be a typical frying of the phone
circuits etc. When I checked it out, the relay coil was open circuit. This
of course is on the control cctry and not the telecom side. I replaced the
relay and it worked perfectly. Can only assume it was a coincidence since
if it was a voltage surge it should have taken out the semis on the relay
drive.

Robert Redelmeier wrote:

In comp.sys.ibm.pc.hardware.chips keith wrote:

glass-encapsulated diode from his pile-o-parts, bent the
leads about 3/4" apart and grabbed it with long-nosed pliers.
He then shoved it into the mains outlet and sure enough it lit
up, and quite brightly too! He did make some comment about
his reliability problems, or some such. I just about PMP. ;-)


Well, OK. But now traffic engineers are installing LED traffic
light replacement bulbs specifically _for_ reliability?

You missed the 'joke'. It wasn't an 'LED', it was a 'diode' raised to
catastrophic incandescence from being fried to hell and back. Of course,
one *could* call it a 'light emitting diode', for a few milliseconds, but
it hardly works on the same principle.


Daisy chain a dozen or so LEDs all facing one way, and plug it in.
Face another set the other way. Parallel as many as you need for
brightness. Nicely vibration resistant.

-- Robert

On Wed, 06 Oct 2004 23:50:49 -0500, David Maynard wrote:

keith wrote:

On Wed, 06 Oct 2004 15:56:56 +1000, Lionel wrote:


Kibo informs me that keith stated that:


On Tue, 05 Oct 2004 03:47:13 +0000, NSM wrote:

"keith" wrote in message
news
| So do engineers when they're bringing up a system where all
| of the tantallums were inserted backwards. You want to see fireworks!
| (well,it was 25 years ago - I've mostly recovered and the tinninus
| isn't so bad. twitch)

grin They don't smell too good either.


Hot electricity never smells good. ...ever notice that? ;-)


I recall being told of a large TTL circuit board which was powered up with
reverse polarity. This was noticed due to the considerable amount of heat
being given off.

Everyone was mystified when the correctly rewired board worked OK. I guess
TTL is a little more tolerant than is generally believed.

TTL protection diodes are as strong as moose!

Well, the individual diodes aren't all that strong, but there's one on
every single I/O pin on every chip, so on a big PCB, the load will be
spread over a *lot* of diodes.


I've pumped several amps though individual ones, but you're right with
thousands in parallel it's tough to smoke 'em. It *can* be done, but...

Unless the chips got hot
enough to let the magic smoke out, they'll likely survive, though
perhaps somewhat injured.

Yup. The best I've personally seen was the time I accidentally plugged a
2716 EPROM backwards into a programmer. It lit up like a xmas tree
through the UV window, but worked fine when I turned it around the right
way.


Oh, my! I've never done that. However...

One time back in the '60s (when I was a mere lad playing with electronics)
a friend and I were talking about these new-fangled LED thingys. He said
they were no big deal and had them for some time. He then took a
small-signal glass-encapsulated diode from his pile-o-parts, bent the
leads about 3/4" apart and grabbed it with long-nosed pliers. He then
shoved it into the mains outlet and sure enough it lit up, and quite
brightly too! He did make some comment about his reliability problems, or
some such. I just about PMP. ;-)


A bit on the high side with power consumption too, I'll wager. hehe

Given the temperature, it was likely more efficient than the average
incandescent bulb. ;-)

--
Keith

On Thu, 07 Oct 2004 12:27:08 +0000, Robert Redelmeier wrote:

In comp.sys.ibm.pc.hardware.chips keith wrote:
glass-encapsulated diode from his pile-o-parts, bent the
leads about 3/4" apart and grabbed it with long-nosed pliers.
He then shoved it into the mains outlet and sure enough it lit
up, and quite brightly too! He did make some comment about
his reliability problems, or some such. I just about PMP. ;-)

Well, OK. But now traffic engineers are installing LED traffic
light replacement bulbs specifically _for_ reliability?

They're more efficient too. LEDs are a few times more efficeint and the
monochromatic light is particularly suited for traffic lights. OTOH, in
the '60s...

Also note that some cars are using LEDs for tail lights. Headlights
are still a bit of a problem.

Daisy chain a dozen or so LEDs all facing one way, and plug it in. Face
another set the other way. Parallel as many as you need for brightness.
Nicely vibration resistant.

Hmm, face another set the other way and you can plug 'em into AC. I
thought these things were a tad more specialized than that though.

--
Keith

On Thu, 07 Oct 2004 08:19:53 -0700, JAD wrote:

reliability and power consumption,,,,,,,,,,,,,,,,
speaking of street lights I was reading yesterday that a number a US
cities are being investigated about their manipulation of the traffic
signals to burn more gas, thus creating revenue for the city, (gas
city level taxes)

I thought that was all about red-light cameras (a real scam!).

--
Keith

On Thu, 07 Oct 2004 19:39:18 -0500, David Maynard wrote:

Robert Redelmeier wrote:

In comp.sys.ibm.pc.hardware.chips keith wrote:

glass-encapsulated diode from his pile-o-parts, bent the
leads about 3/4" apart and grabbed it with long-nosed pliers.
He then shoved it into the mains outlet and sure enough it lit
up, and quite brightly too! He did make some comment about
his reliability problems, or some such. I just about PMP. ;-)


Well, OK. But now traffic engineers are installing LED traffic
light replacement bulbs specifically _for_ reliability?

You missed the 'joke'. It wasn't an 'LED', it was a 'diode' raised to
catastrophic incandescence from being fried to hell and back. Of course,
one *could* call it a 'light emitting diode', for a few milliseconds, but
it hardly works on the same principle.

I'm quite sure Robert got it. He knows my silliness well (though may not
admit it

snip

--
Keith

"Geoff C" wrote in message
...
keith wrote in
news
One time back in the '60s (when I was a mere lad playing with
electronics) a friend and I were talking about these new-fangled LED
thingys. He said they were no big deal and had them for some time. He
then took a small-signal glass-encapsulated diode from his
pile-o-parts, bent the leads about 3/4" apart and grabbed it with
long-nosed pliers. He then shoved it into the mains outlet and sure
enough it lit up, and quite brightly too!

I once had a bizarre failure of a USR modem immediately after a
thunderstorm. You would think it would be a typical frying of the phone
circuits etc. When I checked it out, the relay coil was open circuit. This
of course is on the control cctry and not the telecom side. I replaced the
relay and it worked perfectly. Can only assume it was a coincidence since
if it was a voltage surge it should have taken out the semis on the relay
drive.


Lightning can cause some very bizarre failures indeed. I had a USR modem
years ago that failed after a nearby lightning strike (rare here) and the
problem turned out to be a 10 ohm surface mount resistor with a crater in
it. Replaced it with a normal resistor and it worked fine until it was
retired years later.

"James Sweet" wrote in message
news:jcp9d.5644$eq1.2343@trnddc08...

| Lightning can cause some very bizarre failures indeed. I had a USR modem
| years ago that failed after a nearby lightning strike (rare here) and the
| problem turned out to be a 10 ohm surface mount resistor with a crater in
| it. Replaced it with a normal resistor and it worked fine until it was
| retired years later.

What most people think is caused by lightning is really caused by induction.
A direct lightning strike will turn your computer etc. into a pile of
bubbling slag. A strike near the phone line causing induction elsewhere will
zap things in very odd ways.

N

In comp.sys.ibm.pc.hardware.chips keith wrote:
I'm quite sure Robert got it. He knows my silliness well

Entirely too well! I'm convinced you were either trying
to demonstrate prior art or "obvious to a skilled practioner
in the art" to invalidate the LED patent, and show the
general silliness of most patents.

(though may not admit it

Why not play the straight man?

-- Robert

On Fri, 08 Oct 2004 17:13:19 +0000, Robert Redelmeier wrote:

In comp.sys.ibm.pc.hardware.chips keith wrote:
I'm quite sure Robert got it. He knows my silliness well

Entirely too well! I'm convinced you were either trying
to demonstrate prior art or "obvious to a skilled practioner
in the art" to invalidate the LED patent, and show the
general silliness of most patents.

Naw, just busting chops. I would *never* demonstrate such! I have such
"silliness" and a few more in the pipe. It's a profitable endeavor. ;-)

(though may not admit it

Why not play the straight man?

Ok, perhaps I will some day! ;-)

--
Keith