Dumb question regarding SMPS

[Joerg]

On Wed, 10 Oct 2012 14:11:58 -0700, John Larkin

On Wed, 10 Oct 2012 15:44:56 -0400, "[email protected]"

On Wed, 10 Oct 2012 11:38:45 -0700, John Larkin

]

Oh, and there is no way to obsolete a component from the database. We have
thousands of capacitors to go through that the manufacturer no longer makes.
These have to be scrubbed every time we put a BOM together.
We never delete a part from our database, but some parts are
"retired." They are physically removed from the stock room, and either
disposed of, or stashed elsewhere in case engineering might want to
play with a few for some reason.
Nope. No way to "retire" them from the schematic database. Everything shows
up the same.
Oh, we can delete parts from the PADS library, and sometimes do. We
could, but don't, delete parts from our inventory database, which is a
different thing.
Certainly it's a different thing. I'll bet it's marked so your purchasing
can't buy it, too. These components aren't marked in any way. They're
perfectly good parts, as far as the capture program is concerned.

Like I said, this is just a small part of the broken system. It's amazing
that anyone is worried about the Asians.

That's what people in Detroit said about 40 years ago. Later this turned
to "Oh s..t!" but it was too late and their companies fell apart. We had
to bail them out because of that major mistake.

It's exactly the opposite. *THEIR* processes *suck*.

Huh? Whose and what processes?

...and look where Japan is now.

Japan does not have China as their money source, for obvious reasons.
The companies there are doing rather well. There is a reason why so many
people drive Toyotas.

 

[Joerg]

[...]

The 100PQFP I am using right now doesn't even fill 1/10th of a regular
letter A here. So how many pins do yours have? 3000?

No wonder you still use such poor practices. You think 100 is big. I have at
least ten parts on a schematic larger than that. The DSPs are >300 pins (one
500 and one >700). We also have several QFP144s. It's not *so* bad with the
dinky 38pin flat-packs but it's still a mess trying to squeeze in terminations
and capacitors next to the pins, since they're not pinned out logically.

I have no problems with that, and neither do any of my clients.

[...]

Evidently there are a lot of idiots. It's done in the highest reliability
industries.

I brought you an example from your former employer and that is a darn
good company when it comes to quality. Yet they had BGA problems galore.
I could have told them.

[...]

They do have to be done right, of course. ...
Does this mean lots of laptop manufacturers including your former
employer do it wrong? This is how it looks when BGA solder joints on
their laptops give up:
Probably. Nothing would surprise me from the PC Co.

Sorry can't watch videos. My laptop will blow up. ;-)

It's an IBM T40 with BGA failure. Lots of other brands have the same issues.
QFPs have never failed? I can tell you otherwise!

Anything with flexible leads in there generally fails less in harsh
environments because there is compliance in the links. This is why I am
using LFPAK FETs on the design I am working on right now. Because they
have real legs on one side and the unit can poptentially be dropped onto
concrete once in a while, as can just about anything.
Your theory sounds plausible but it's not reality.

It is reality. It's been tested but I can't copy those docs because then
I'd get shot. The failures usually happen under two test conditions,
vibration and rapid temp-cycling.
No, it certainly isn't. BGAs are *very* reliable. The military wouldn't be
using them otherwise. They don't do RoHS and that's a RPITA, but they have
*no* problems with BGAs. Automotive, another harsh long-life environment,
ditto.

Don't get me started on automotive electronics ...

Oh, well. BGAs *are* reliable.

Your choice. I am of a very different opinion.

[...]

 

[[email protected]]

[email protected] wrote:
On Wed, 10 Oct 2012 14:11:58 -0700, John Larkin

On Wed, 10 Oct 2012 15:44:56 -0400, "[email protected]"

On Wed, 10 Oct 2012 11:38:45 -0700, John Larkin

On Wed, 10 Oct 2012 13:46:33 -0400, "[email protected]"

[...]

Oh, and there is no way to obsolete a component from the database. We have
thousands of capacitors to go through that the manufacturer no longer makes.
These have to be scrubbed every time we put a BOM together.
We never delete a part from our database, but some parts are
"retired." They are physically removed from the stock room, and either
disposed of, or stashed elsewhere in case engineering might want to
play with a few for some reason.
Nope. No way to "retire" them from the schematic database. Everything shows
up the same.
Oh, we can delete parts from the PADS library, and sometimes do. We
could, but don't, delete parts from our inventory database, which is a
different thing.
Certainly it's a different thing. I'll bet it's marked so your purchasing
can't buy it, too. These components aren't marked in any way. They're
perfectly good parts, as far as the capture program is concerned.

Like I said, this is just a small part of the broken system. It's amazing
that anyone is worried about the Asians.

That's what people in Detroit said about 40 years ago. Later this turned
to "Oh s..t!" but it was too late and their companies fell apart. We had
to bail them out because of that major mistake.

It's exactly the opposite. *THEIR* processes *suck*.

Huh? Whose and what processes?

Japanese. From what I see, the Chinese are even worse.

Japan does not have China as their money source, for obvious reasons.

Good grief, twenty years ago the bogeyman was Japan. Before that SA.

The companies there are doing rather well. There is a reason why so many
people drive Toyotas.

....built, now designed, in the US. THe difference is unions, not so much
processed.

 

[[email protected]]

[email protected] wrote:

[email protected] wrote:

[email protected] wrote:

[...]

The 100PQFP I am using right now doesn't even fill 1/10th of a regular
letter A here. So how many pins do yours have? 3000?

No wonder you still use such poor practices. You think 100 is big. I have at
least ten parts on a schematic larger than that. The DSPs are >300 pins (one
500 and one >700). We also have several QFP144s. It's not *so* bad with the
dinky 38pin flat-packs but it's still a mess trying to squeeze in terminations
and capacitors next to the pins, since they're not pinned out logically.

I have no problems with that, and neither do any of my clients.

Your stuff is tiny. ...and you don't care if it's a mess. ;-)

I brought you an example from your former employer and that is a darn
good company when it comes to quality. Yet they had BGA problems galore.
I could have told them.

My PPoE hasn't done that sort of work in several decades. THey were quite
good at it, though.

[...]


They do have to be done right, of course. ...
Does this mean lots of laptop manufacturers including your former
employer do it wrong? This is how it looks when BGA solder joints on
their laptops give up:
Probably. Nothing would surprise me from the PC Co.

Sorry can't watch videos. My laptop will blow up. ;-)

It's an IBM T40 with BGA failure. Lots of other brands have the same issues.
QFPs have never failed? I can tell you otherwise!

Anything with flexible leads in there generally fails less in harsh
environments because there is compliance in the links. This is why I am
using LFPAK FETs on the design I am working on right now. Because they
have real legs on one side and the unit can poptentially be dropped onto
concrete once in a while, as can just about anything.
Your theory sounds plausible but it's not reality.

It is reality. It's been tested but I can't copy those docs because then
I'd get shot. The failures usually happen under two test conditions,
vibration and rapid temp-cycling.
No, it certainly isn't. BGAs are *very* reliable. The military wouldn't be
using them otherwise. They don't do RoHS and that's a RPITA, but they have
*no* problems with BGAs. Automotive, another harsh long-life environment,
ditto.

Don't get me started on automotive electronics ...

Oh, well. BGAs *are* reliable.

Your choice. I am of a very different opinion.

You're welcome to your own opinions but not your own facts.

 

[Joerg]

[email protected] wrote:
On Wed, 10 Oct 2012 14:11:58 -0700, John Larkin

On Wed, 10 Oct 2012 15:44:56 -0400, "[email protected]"

On Wed, 10 Oct 2012 11:38:45 -0700, John Larkin

On Wed, 10 Oct 2012 13:46:33 -0400, "[email protected]"

[...]

Oh, and there is no way to obsolete a component from the database. We have
thousands of capacitors to go through that the manufacturer no longer makes.
These have to be scrubbed every time we put a BOM together.
We never delete a part from our database, but some parts are
"retired." They are physically removed from the stock room, and either
disposed of, or stashed elsewhere in case engineering might want to
play with a few for some reason.
Nope. No way to "retire" them from the schematic database. Everything shows
up the same.
Oh, we can delete parts from the PADS library, and sometimes do. We
could, but don't, delete parts from our inventory database, which is a
different thing.
Certainly it's a different thing. I'll bet it's marked so your purchasing
can't buy it, too. These components aren't marked in any way. They're
perfectly good parts, as far as the capture program is concerned.

Like I said, this is just a small part of the broken system. It's amazing
that anyone is worried about the Asians.
That's what people in Detroit said about 40 years ago. Later this turned
to "Oh s..t!" but it was too late and their companies fell apart. We had
to bail them out because of that major mistake.
It's exactly the opposite. *THEIR* processes *suck*.

Huh? Whose and what processes?

Japanese. From what I see, the Chinese are even worse.

Maybe you should take the engineer's tour through a company such as
Mitsubishi. That can be an eye-popper.

There is a reason why my car from that company has not had one defect
from day one, over 16 years now. Not even a dome light bulb has dared to
burn out.

Good grief, twenty years ago the bogeyman was Japan. Before that SA.

SA?

According to guys in Detroit their bogeyman _is_ still Japan. Well, plus
South Korea now.

...built, now designed, in the US. THe difference is unions, not so much
processed.

My car was designed and built in Nagoya. That's not in the US.

 

[Joerg]

Your stuff is tiny. ...and you don't care if it's a mess. ;-)

Clearly you have not seen the schematics of a 128-channel ultrasound
machine.

[...]

You're welcome to your own opinions but not your own facts.

I know the facts, and they show that BGAs cause reliability issues.

 

[[email protected]]

[email protected] wrote:

[email protected] wrote:
On Wed, 10 Oct 2012 14:11:58 -0700, John Larkin

On Wed, 10 Oct 2012 15:44:56 -0400, "[email protected]"

On Wed, 10 Oct 2012 11:38:45 -0700, John Larkin

On Wed, 10 Oct 2012 13:46:33 -0400, "[email protected]"

[...]

Oh, and there is no way to obsolete a component from the database. We have
thousands of capacitors to go through that the manufacturer no longer makes.
These have to be scrubbed every time we put a BOM together.
We never delete a part from our database, but some parts are
"retired." They are physically removed from the stock room, and either
disposed of, or stashed elsewhere in case engineering might want to
play with a few for some reason.
Nope. No way to "retire" them from the schematic database. Everything shows
up the same.
Oh, we can delete parts from the PADS library, and sometimes do. We
could, but don't, delete parts from our inventory database, which is a
different thing.
Certainly it's a different thing. I'll bet it's marked so your purchasing
can't buy it, too. These components aren't marked in any way. They're
perfectly good parts, as far as the capture program is concerned.

Like I said, this is just a small part of the broken system. It's amazing
that anyone is worried about the Asians.
That's what people in Detroit said about 40 years ago. Later this turned
to "Oh s..t!" but it was too late and their companies fell apart. We had
to bail them out because of that major mistake.
It's exactly the opposite. *THEIR* processes *suck*.

Huh? Whose and what processes?

Japanese. From what I see, the Chinese are even worse.

Maybe you should take the engineer's tour through a company such as
Mitsubishi. That can be an eye-popper.

Manufacturing, not engineering control.

There is a reason why my car from that company has not had one defect
from day one, over 16 years now. Not even a dome light bulb has dared to
burn out.

SA?

Saudi Arabia.

According to guys in Detroit their bogeyman _is_ still Japan. Well, plus
South Korea now.

Except that the cars are built *here*. For at least the last 20 years,
Detroit's problems have been production more than engineering. Detroit's real
bogeyman is *UNIONS*, something neither Japan or Korea (or their US entities)
has any worry about.

My car was designed and built in Nagoya. That's not in the US.

Last century, perhaps.

 

[[email protected]]

[email protected] wrote:

[email protected] wrote:

[email protected] wrote:

[email protected] wrote:
[...]



The 100PQFP I am using right now doesn't even fill 1/10th of a regular
letter A here. So how many pins do yours have? 3000?
No wonder you still use such poor practices. You think 100 is big. I have at
least ten parts on a schematic larger than that. The DSPs are >300 pins (one
500 and one >700). We also have several QFP144s. It's not *so* bad with the
dinky 38pin flat-packs but it's still a mess trying to squeeze in terminations
and capacitors next to the pins, since they're not pinned out logically.

I have no problems with that, and neither do any of my clients.

Your stuff is tiny. ...and you don't care if it's a mess. ;-)

Clearly you have not seen the schematics of a 128-channel ultrasound
machine.

You think a 100 pin QFN is big. QED. OTOH, mainframes *are* big.

I know the facts, and they show that BGAs cause reliability issues.

Bullshit. BGAs are *very* reliable. They wouldn't be in military equipment if
they were anywhere near as bad as you dream.

 

[Joerg]

[email protected] wrote:

[email protected] wrote:
On Wed, 10 Oct 2012 14:11:58 -0700, John Larkin

On Wed, 10 Oct 2012 15:44:56 -0400, "[email protected]"

On Wed, 10 Oct 2012 11:38:45 -0700, John Larkin

On Wed, 10 Oct 2012 13:46:33 -0400, "[email protected]"

[...]

Oh, and there is no way to obsolete a component from the database. We have
thousands of capacitors to go through that the manufacturer no longer makes.
These have to be scrubbed every time we put a BOM together.
We never delete a part from our database, but some parts are
"retired." They are physically removed from the stock room, and either
disposed of, or stashed elsewhere in case engineering might want to
play with a few for some reason.
Nope. No way to "retire" them from the schematic database. Everything shows
up the same.
Oh, we can delete parts from the PADS library, and sometimes do. We
could, but don't, delete parts from our inventory database, which is a
different thing.
Certainly it's a different thing. I'll bet it's marked so your purchasing
can't buy it, too. These components aren't marked in any way. They're
perfectly good parts, as far as the capture program is concerned.

Like I said, this is just a small part of the broken system. It's amazing
that anyone is worried about the Asians.
That's what people in Detroit said about 40 years ago. Later this turned
to "Oh s..t!" but it was too late and their companies fell apart. We had
to bail them out because of that major mistake.
It's exactly the opposite. *THEIR* processes *suck*.

Huh? Whose and what processes?
Japanese. From what I see, the Chinese are even worse.

Maybe you should take the engineer's tour through a company such as
Mitsubishi. That can be an eye-popper.

Manufacturing, not engineering control.

It's both. Good engineering control and good manufacturing go hand in
hand. For technical goods one cannot really exist without the other.

Good grief. Anecdote <> evidence.

Obviously you do not read Consumer Reports. I do, and most deinitely
before making a big purcahsing decision like buying a car.

Saudi Arabia.


Except that the cars are built *here*. For at least the last 20 years,
Detroit's problems have been production more than engineering. Detroit's real
bogeyman is *UNIONS*, something neither Japan or Korea (or their US entities)
has any worry about.

Sure, because every time the unions made a demand the big three rolled
over and played dead. Nonsense such as jobs banks.

Last century, perhaps.

Nope, still built in Nagoya.

 

[Joerg]

[snip]

There is a reason why my car from that company has not had one defect
from day one, over 16 years now. Not even a dome light bulb has dared to
burn out.
Good grief. Anecdote <> evidence.

Obviously you do not read Consumer Reports. I do, and most deinitely
before making a big purcahsing decision like buying a car.

[snip]

Consumer's Union supported Obamacare. As a result I cut off not only
my subscription to Consumer Reports (the magazine) but stopped my
charitable contributions to Consumer's Union.

Ok, that was one of many examples. There are statistics the AAA runs,
there's Edmunds, and on and on. It does not take much to figure which
brands are at the top. And wishful thinking isn't going to help in that
domain, only cold hard facts count.

I guess there is a reason why you are driving a Nissan and an Infinity.