ECL logic SPICE models

[krw]

Jim Thompson wrote:
Jim Thompson wrote:
On Sat, 12 Sep 2009 10:01:22 -0700, Jim Thompson

John Larkin wrote:
John Larkin wrote:
[...]

One issue I found with RF devices was that you can sometimes only obtain
small signal simulator models that aren't very helpful with pulse apps,
plus require software that costs more than your Volkswagen. Even with
big LDMOS parts I had that happen. One company (PolyFet) stuck out and
provided SPICE models. So the big competitor will be left out ... sorry,
NXP.
I don't simulate this stuff, I test. Most microwave parts are
characterized small-signal, S-params. Spice models are very rare in
this business. I know things about some of these parts that the
manufacturers don't know.

Lately I have simulated more, and then straight to layout. The one
that's in fab right now is a white-knuckle ride because I am using a
device in a weird way. Usually pans out though.

What often amazes me is how close to abs max people (and sometimes app
notes) bias RF devices. When it says 7V they bias them to 5V or 6V on
the collector/drain. Some day a huge pulse finds its way into the input,
almost saturates the device, then it lets go, the inductor shoots up ...
phut.
I've run 7-volt-rated MESfets at 18 volts, and 2 volt RF schottkies at
6. I sometimes test parts to destruction and then back off some. The
performance is often worth the small risk.

I've seen that. But if you are a consultant and this goes into some
aircraft you can't design like that. Even with an indemnification clause
that can cause lots of grief should it go wrong in only one case. It's
got to be by the book.


Lots of RF devices seem to have voltage ratings that assume an RF tank
in the output, so that the actual instantaneous drain excursion is 0
to twice Vcc. The RF guys are really, really terrible when it comes to
realtime specs. You're lucky to get any DC curves. More often there's
an app circuit with an input match, an output match, and a gate bias
trimpot.

All they really offer in many cases is a set of S-parameters. Since I
design a lot of pulse circuitry I almost do a rain dance every time
there is just a snippet of SPICE data.
Somewhere in my bag-o-tricks is an S-Parameter-to-Spice-Model
converter (and vice-versa).

When I find it I'll post.

...Jim Thompson
All my S-Parameter to Spice stuff has been updated on the SED page of
my website... except a good article by Microcap... get that from their
website, so I don't step on any copyright toes ;-)

Thanks. I assume you mean this link:

http://www.analog-innovations.com/SED/CreateS-ParameterSUBCKTinPSpice.pdf

Now I have to learn QuickBasic, whatever that is ;-)
There are four articles there, each beginning (in the listing),
"S-Param...", all of which are elucidating.

Unless I understand something wrong the first three are for extracting
S-parameters from SPICE or PROBE (Orcad's version of SPICE).

But maybe I'll read them again and some more elucidation will come

Most math is bilateral ;-)

Ok, true, I was lazy here. Thought about some SW-routine where you slap
the datasheet on a scanner, press magic button, out comes SPICE
sub-circuit ))

I can do that for you... for a fee ;-)

You want Joerg pressing your magic buttons? ...for a fee? Ew!

 

[Joerg]

Jim Thompson wrote:

[...]

Young man, queuing up to be cancer-victim-Duane's replacement, is, of
all things, the maintenance shop manager for the Chandler Police
Department...

http://www.analog-innovations.com/SED/AllisonAtMarksShop.JPG

They ride Honda, not Harley? I've never seen police ride Japanese bikes
anywhere. But Folsom PD and the CHP use BMW.

It unfortunately isn't that simple. Data sheets aren't generally very
accurate. So modeling requires a fancy measurements lab, to do it
right.

I just wondered whether they didn't use SPICE to model the device before
release to production. Maybe they didn't.

Converting formats can, however, be easily automated. I have a bunch
of UltraEdit macros to re-write HSpice libraries to PSpice libraries,
but need to combine it all into a script, so all human input can be
removed ;-)

Also fixing dumb-ass stuff created by empty-minded PhD's...

e.g., changing MOS parameter SX=1.499999969e-6 to SX=1.5u ;-)

It probably came out of someone's calculator so they just typed it in.
In order not to make a mistake ...

 

[Charlie E.]

John Larkin wrote:
[...]


One issue I found with RF devices was that you can sometimes only obtain
small signal simulator models that aren't very helpful with pulse apps,
plus require software that costs more than your Volkswagen. Even with
big LDMOS parts I had that happen. One company (PolyFet) stuck out and
provided SPICE models. So the big competitor will be left out ... sorry,
NXP.
I don't simulate this stuff, I test. Most microwave parts are
characterized small-signal, S-params. Spice models are very rare in
this business. I know things about some of these parts that the
manufacturers don't know.

Lately I have simulated more, and then straight to layout. The one
that's in fab right now is a white-knuckle ride because I am using a
device in a weird way. Usually pans out though.

What often amazes me is how close to abs max people (and sometimes app
notes) bias RF devices. When it says 7V they bias them to 5V or 6V on
the collector/drain. Some day a huge pulse finds its way into the input,
almost saturates the device, then it lets go, the inductor shoots up ...
phut.

I've run 7-volt-rated MESfets at 18 volts, and 2 volt RF schottkies at
6. I sometimes test parts to destruction and then back off some. The
performance is often worth the small risk.

I've seen that. But if you are a consultant and this goes into some
aircraft you can't design like that. Even with an indemnification clause
that can cause lots of grief should it go wrong in only one case. It's
got to be by the book.

Lots of RF devices seem to have voltage ratings that assume an RF tank
in the output, so that the actual instantaneous drain excursion is 0
to twice Vcc. The RF guys are really, really terrible when it comes to
realtime specs. You're lucky to get any DC curves. More often there's
an app circuit with an input match, an output match, and a gate bias
trimpot.

All they really offer in many cases is a set of S-parameters. Since I
design a lot of pulse circuitry I almost do a rain dance every time
there is just a snippet of SPICE data.

Somewhere in my bag-o-tricks is an S-Parameter-to-Spice-Model
converter (and vice-versa).

When I find it I'll post.

...Jim Thompson

Yes, Jim, I think I sent that to you back in the day. But, you have
to be careful. It really does what is in effect an inverse FFT of the
Sparams, so it doesn't include any of the really important data you
need to do a good spice simulation when you are concerned more with
transient response. IBIS models are a 'little' better, but they are
also very behavioral and I was always interested in the little
'gotchas' that following them too closely led to.

Charlie

 

[Charlie E.]

It unfortunately isn't that simple. Data sheets aren't generally very
accurate. So modeling requires a fancy measurements lab, to do it
right.

Converting formats can, however, be easily automated. I have a bunch
of UltraEdit macros to re-write HSpice libraries to PSpice libraries,
but need to combine it all into a script, so all human input can be
removed ;-)

Also fixing dumb-ass stuff created by empty-minded PhD's...

e.g., changing MOS parameter SX=1.499999969e-6 to SX=1.5u ;-)

...Jim Thompson

Yeah, back in the day at Microsim, there were two guys that had a
space lined with curve tracers, oscilloscopes, power supplies and
signal generators whose job was to verify that the models and the
actual parts agreed with each other, especially when they were doing
the digital I/O models. When Orcad and Cadence came in, they were the
first ones to go.

Charlie

 

[Joerg]

John Larkin wrote:
John Larkin wrote:
[...]

One issue I found with RF devices was that you can sometimes only obtain
small signal simulator models that aren't very helpful with pulse apps,
plus require software that costs more than your Volkswagen. Even with
big LDMOS parts I had that happen. One company (PolyFet) stuck out and
provided SPICE models. So the big competitor will be left out ... sorry,
NXP.
I don't simulate this stuff, I test. Most microwave parts are
characterized small-signal, S-params. Spice models are very rare in
this business. I know things about some of these parts that the
manufacturers don't know.

Lately I have simulated more, and then straight to layout. The one
that's in fab right now is a white-knuckle ride because I am using a
device in a weird way. Usually pans out though.

What often amazes me is how close to abs max people (and sometimes app
notes) bias RF devices. When it says 7V they bias them to 5V or 6V on
the collector/drain. Some day a huge pulse finds its way into the input,
almost saturates the device, then it lets go, the inductor shoots up ...
phut.
I've run 7-volt-rated MESfets at 18 volts, and 2 volt RF schottkies at
6. I sometimes test parts to destruction and then back off some. The
performance is often worth the small risk.

I've seen that. But if you are a consultant and this goes into some
aircraft you can't design like that. Even with an indemnification clause
that can cause lots of grief should it go wrong in only one case. It's
got to be by the book.


Lots of RF devices seem to have voltage ratings that assume an RF tank
in the output, so that the actual instantaneous drain excursion is 0
to twice Vcc. The RF guys are really, really terrible when it comes to
realtime specs. You're lucky to get any DC curves. More often there's
an app circuit with an input match, an output match, and a gate bias
trimpot.

All they really offer in many cases is a set of S-parameters. Since I
design a lot of pulse circuitry I almost do a rain dance every time
there is just a snippet of SPICE data.

Somewhere in my bag-o-tricks is an S-Parameter-to-Spice-Model
converter (and vice-versa).

When I find it I'll post.

...Jim Thompson

Yes, Jim, I think I sent that to you back in the day. But, you have
to be careful. It really does what is in effect an inverse FFT of the
Sparams, so it doesn't include any of the really important data you
need to do a good spice simulation when you are concerned more with
transient response.

That's exactly the point, especially with LDMOS. When a big old fat one
goes phut ... *KABLAM* it's mucho Dolares down the drain. Not the best
way to make friends at a new client.

 

[Joerg]

Charlie E. wrote: [snip]

Yes, Jim, I think I sent that to you back in the day. But, you have
to be careful. It really does what is in effect an inverse FFT of the
Sparams, so it doesn't include any of the really important data you
need to do a good spice simulation when you are concerned more with
transient response.

That's exactly the point, especially with LDMOS. When a big old fat one
goes phut ... *KABLAM* it's mucho Dolares down the drain. Not the best
way to make friends at a new client.

... IBIS models are a 'little' better, but they are
also very behavioral and I was always interested in the little
'gotchas' that following them too closely led to.

Charlie

Joerg, You have way too much "phut ... *KABLAM*" in your life! What
is it you're doing to cause all that ?

Crikey! Here I am months from the big '70, and I can count all my
"phut ... *KABLAM*"'s on one hand... and they were ALL in the lab, NOT
in the field, just great entertainment for my technicians... nothing
quite like the boss getting knocked off his lab stool to amuse the
troops ;-)

Mine are also in the lab. It usually happens when we try to push the
envelope a bit too much, when models don't jibe or when something else
breaks down and causes a huge reflection or things like that. I do a lot
of heavy duty pulse stuff where this is a normal part of life.

You are doing IC design. That's like signal corp versus a job in the
artillery. I did some chip designs as well but only a few and, you
guessed it, those are run hard along the kablam ridge. "But this will
electromigrate itself to death" ... "We have no real estate, got to do
it" ... "Yabbut, the design rules and all that" ..."It only needs to
live a few hours" ... "Oh".

 

[krw]

Charlie E. wrote: [snip]
Yes, Jim, I think I sent that to you back in the day. But, you have
to be careful. It really does what is in effect an inverse FFT of the
Sparams, so it doesn't include any of the really important data you
need to do a good spice simulation when you are concerned more with
transient response.

That's exactly the point, especially with LDMOS. When a big old fat one
goes phut ... *KABLAM* it's mucho Dolares down the drain. Not the best
way to make friends at a new client.


... IBIS models are a 'little' better, but they are
also very behavioral and I was always interested in the little
'gotchas' that following them too closely led to.

Charlie

Joerg, You have way too much "phut ... *KABLAM*" in your life! What
is it you're doing to cause all that ?

Crikey! Here I am months from the big '70, and I can count all my
"phut ... *KABLAM*"'s on one hand... and they were ALL in the lab, NOT
in the field, just great entertainment for my technicians... nothing
quite like the boss getting knocked off his lab stool to amuse the
troops ;-)

Mine are also in the lab. It usually happens when we try to push the
envelope a bit too much, when models don't jibe or when something else
breaks down and causes a huge reflection or things like that. I do a lot
of heavy duty pulse stuff where this is a normal part of life.

You are doing IC design. That's like signal corp versus a job in the
artillery. I did some chip designs as well but only a few and, you
guessed it, those are run hard along the kablam ridge. "But this will
electromigrate itself to death" ... "We have no real estate, got to do
it" ... "Yabbut, the design rules and all that" ..."It only needs to
live a few hours" ... "Oh".

Oops. It didn't.

 

[Joerg]

Charlie E. wrote:
[snip]
Yes, Jim, I think I sent that to you back in the day. But, you have
to be careful. It really does what is in effect an inverse FFT of the
Sparams, so it doesn't include any of the really important data you
need to do a good spice simulation when you are concerned more with
transient response.
That's exactly the point, especially with LDMOS. When a big old fat one
goes phut ... *KABLAM* it's mucho Dolares down the drain. Not the best
way to make friends at a new client.


... IBIS models are a 'little' better, but they are
also very behavioral and I was always interested in the little
'gotchas' that following them too closely led to.

Charlie
Joerg, You have way too much "phut ... *KABLAM*" in your life! What
is it you're doing to cause all that ?

Crikey! Here I am months from the big '70, and I can count all my
"phut ... *KABLAM*"'s on one hand... and they were ALL in the lab, NOT
in the field, just great entertainment for my technicians... nothing
quite like the boss getting knocked off his lab stool to amuse the
troops ;-)

Mine are also in the lab. It usually happens when we try to push the
envelope a bit too much, when models don't jibe or when something else
breaks down and causes a huge reflection or things like that. I do a lot
of heavy duty pulse stuff where this is a normal part of life.

You are doing IC design. That's like signal corp versus a job in the
artillery. I did some chip designs as well but only a few and, you
guessed it, those are run hard along the kablam ridge. "But this will
electromigrate itself to death" ... "We have no real estate, got to do
it" ... "Yabbut, the design rules and all that" ..."It only needs to
live a few hours" ... "Oh".

Oops. It didn't.

They all do

 

[Joerg]

Charlie E. wrote:
[snip]
Yes, Jim, I think I sent that to you back in the day. But, you have
to be careful. It really does what is in effect an inverse FFT of the
Sparams, so it doesn't include any of the really important data you
need to do a good spice simulation when you are concerned more with
transient response.
That's exactly the point, especially with LDMOS. When a big old fat one
goes phut ... *KABLAM* it's mucho Dolares down the drain. Not the best
way to make friends at a new client.


... IBIS models are a 'little' better, but they are
also very behavioral and I was always interested in the little
'gotchas' that following them too closely led to.

Charlie
Joerg, You have way too much "phut ... *KABLAM*" in your life! What
is it you're doing to cause all that ?

Crikey! Here I am months from the big '70, and I can count all my
"phut ... *KABLAM*"'s on one hand... and they were ALL in the lab, NOT
in the field, just great entertainment for my technicians... nothing
quite like the boss getting knocked off his lab stool to amuse the
troops ;-)

Mine are also in the lab. It usually happens when we try to push the
envelope a bit too much, when models don't jibe or when something else
breaks down and causes a huge reflection or things like that. I do a lot
of heavy duty pulse stuff where this is a normal part of life.

You are doing IC design. That's like signal corp versus a job in the
artillery.

What a pile of horse pucky. Who do you think did Hubble magnetic
support, a satellite spinner for objects as big as a car, and
automotive environment for years and years and years ?

Then why does the electronics in cars croak so often ... ?

<duck and run>

 

[Joerg]

Jim Thompson wrote:
Charlie E. wrote:
[snip]
Yes, Jim, I think I sent that to you back in the day. But, you have
to be careful. It really does what is in effect an inverse FFT of the
Sparams, so it doesn't include any of the really important data you
need to do a good spice simulation when you are concerned more with
transient response.
That's exactly the point, especially with LDMOS. When a big old fat one
goes phut ... *KABLAM* it's mucho Dolares down the drain. Not the best
way to make friends at a new client.


... IBIS models are a 'little' better, but they are
also very behavioral and I was always interested in the little
'gotchas' that following them too closely led to.

Charlie
Joerg, You have way too much "phut ... *KABLAM*" in your life! What
is it you're doing to cause all that ?

Crikey! Here I am months from the big '70, and I can count all my
"phut ... *KABLAM*"'s on one hand... and they were ALL in the lab, NOT
in the field, just great entertainment for my technicians... nothing
quite like the boss getting knocked off his lab stool to amuse the
troops ;-)
Mine are also in the lab. It usually happens when we try to push the
envelope a bit too much, when models don't jibe or when something else
breaks down and causes a huge reflection or things like that. I do a lot
of heavy duty pulse stuff where this is a normal part of life.

You are doing IC design. That's like signal corp versus a job in the
artillery.
What a pile of horse pucky. Who do you think did Hubble magnetic
support, a satellite spinner for objects as big as a car, and
automotive environment for years and years and years ?

Then why does the electronics in cars croak so often ... ?

<duck and run>

Only GM (Government Motors) and Mercedes, judging from local
observation ;-) ...

Wasn't it Ford who managed to place an ingnition controller hybrid or
something similar on top of the engine? I thought that was a rather
stupid thing to do. Probably the cause of issues like "doesn't start
when still warm".

The electrical failures in my Chrysler weren't truly electrical. They
had mounted the alternator on an aluminum strut. Now that was really stupid.

... As you may properly deduce from my postings here, I
am of the big hammer school... if I can't kill it with a big hammer,
get a bigger one. I don't tolerate pansy designers.

As a consultant, I just politely decline when I realize that the rest of
the team ain't up to snuff. After all, that carries some liability risks
with it.

 

[krw]

Jim Thompson wrote:
Charlie E. wrote:
[snip]
Yes, Jim, I think I sent that to you back in the day. But, you have
to be careful. It really does what is in effect an inverse FFT of the
Sparams, so it doesn't include any of the really important data you
need to do a good spice simulation when you are concerned more with
transient response.
That's exactly the point, especially with LDMOS. When a big old fat one
goes phut ... *KABLAM* it's mucho Dolares down the drain. Not the best
way to make friends at a new client.


... IBIS models are a 'little' better, but they are
also very behavioral and I was always interested in the little
'gotchas' that following them too closely led to.

Charlie
Joerg, You have way too much "phut ... *KABLAM*" in your life! What
is it you're doing to cause all that ?

Crikey! Here I am months from the big '70, and I can count all my
"phut ... *KABLAM*"'s on one hand... and they were ALL in the lab, NOT
in the field, just great entertainment for my technicians... nothing
quite like the boss getting knocked off his lab stool to amuse the
troops ;-)

Mine are also in the lab. It usually happens when we try to push the
envelope a bit too much, when models don't jibe or when something else
breaks down and causes a huge reflection or things like that. I do a lot
of heavy duty pulse stuff where this is a normal part of life.

You are doing IC design. That's like signal corp versus a job in the
artillery. I did some chip designs as well but only a few and, you
guessed it, those are run hard along the kablam ridge. "But this will
electromigrate itself to death" ... "We have no real estate, got to do
it" ... "Yabbut, the design rules and all that" ..."It only needs to
live a few hours" ... "Oh".

Oops. It didn't.

They all do

Evidently not the ones that go "phut ... *KABLAM*", unless you're
really a closet pyro. ;-)

 

[krw]

Jim Thompson wrote:
Jim Thompson wrote:
Charlie E. wrote:
[snip]
Yes, Jim, I think I sent that to you back in the day. But, you have
to be careful. It really does what is in effect an inverse FFT of the
Sparams, so it doesn't include any of the really important data you
need to do a good spice simulation when you are concerned more with
transient response.
That's exactly the point, especially with LDMOS. When a big old fat one
goes phut ... *KABLAM* it's mucho Dolares down the drain. Not the best
way to make friends at a new client.


... IBIS models are a 'little' better, but they are
also very behavioral and I was always interested in the little
'gotchas' that following them too closely led to.

Charlie
Joerg, You have way too much "phut ... *KABLAM*" in your life! What
is it you're doing to cause all that ?

Crikey! Here I am months from the big '70, and I can count all my
"phut ... *KABLAM*"'s on one hand... and they were ALL in the lab, NOT
in the field, just great entertainment for my technicians... nothing
quite like the boss getting knocked off his lab stool to amuse the
troops ;-)
Mine are also in the lab. It usually happens when we try to push the
envelope a bit too much, when models don't jibe or when something else
breaks down and causes a huge reflection or things like that. I do a lot
of heavy duty pulse stuff where this is a normal part of life.

You are doing IC design. That's like signal corp versus a job in the
artillery.
What a pile of horse pucky. Who do you think did Hubble magnetic
support, a satellite spinner for objects as big as a car, and
automotive environment for years and years and years ?

Then why does the electronics in cars croak so often ... ?

<duck and run>

Only GM (Government Motors) and Mercedes, judging from local
observation ;-) ...

Wasn't it Ford who managed to place an ingnition controller hybrid or
something similar on top of the engine?

Yep, it was called a "carburetor". ;-)

I thought that was a rather
stupid thing to do. Probably the cause of issues like "doesn't start
when still warm".

That's the one.

The electrical failures in my Chrysler weren't truly electrical. They
had mounted the alternator on an aluminum strut. Now that was really stupid.

Chrysler's body didn't last long enough for the electronics to be
stressed.

As a consultant, I just politely decline when I realize that the rest of
the team ain't up to snuff. After all, that carries some liability risks
with it.

Consult for the government. No worries at all.

 

[Joerg]

Jim Thompson wrote:
Jim Thompson wrote:
Charlie E. wrote:
[snip]
Yes, Jim, I think I sent that to you back in the day. But, you have
to be careful. It really does what is in effect an inverse FFT of the
Sparams, so it doesn't include any of the really important data you
need to do a good spice simulation when you are concerned more with
transient response.
That's exactly the point, especially with LDMOS. When a big old fat one
goes phut ... *KABLAM* it's mucho Dolares down the drain. Not the best
way to make friends at a new client.


... IBIS models are a 'little' better, but they are
also very behavioral and I was always interested in the little
'gotchas' that following them too closely led to.

Charlie
Joerg, You have way too much "phut ... *KABLAM*" in your life! What
is it you're doing to cause all that ?

Crikey! Here I am months from the big '70, and I can count all my
"phut ... *KABLAM*"'s on one hand... and they were ALL in the lab, NOT
in the field, just great entertainment for my technicians... nothing
quite like the boss getting knocked off his lab stool to amuse the
troops ;-)
Mine are also in the lab. It usually happens when we try to push the
envelope a bit too much, when models don't jibe or when something else
breaks down and causes a huge reflection or things like that. I do a lot
of heavy duty pulse stuff where this is a normal part of life.

You are doing IC design. That's like signal corp versus a job in the
artillery.
What a pile of horse pucky. Who do you think did Hubble magnetic
support, a satellite spinner for objects as big as a car, and
automotive environment for years and years and years ?

Then why does the electronics in cars croak so often ... ?

<duck and run>
Only GM (Government Motors) and Mercedes, judging from local
observation ;-) ...

Wasn't it Ford who managed to place an ingnition controller hybrid or
something similar on top of the engine? I thought that was a rather
stupid thing to do. Probably the cause of issues like "doesn't start
when still warm".

I was referring to contemporary auto manufacturers. Back in time Ford
certainly had their issues... mostly mechanical. In the late '60's
(IIRC) Ford was fond of their ad, "... brighter idea", with a
hand-held light bulb. I had my technician blow out a whole case of
100W light bulbs, then sent them to Arnold Thibideau, electrical
engineering manager at the Dearborn operation ;-)

Did he explode on you?

Same here, though I'm more often inclined to make them out as asses
during a heavily attended design review ;-)

I'd never, ever do that.

 

[Joerg]

Jim Thompson wrote:
Charlie E. wrote:
[snip]
Yes, Jim, I think I sent that to you back in the day. But, you have
to be careful. It really does what is in effect an inverse FFT of the
Sparams, so it doesn't include any of the really important data you
need to do a good spice simulation when you are concerned more with
transient response.
That's exactly the point, especially with LDMOS. When a big old fat one
goes phut ... *KABLAM* it's mucho Dolares down the drain. Not the best
way to make friends at a new client.


... IBIS models are a 'little' better, but they are
also very behavioral and I was always interested in the little
'gotchas' that following them too closely led to.

Charlie
Joerg, You have way too much "phut ... *KABLAM*" in your life! What
is it you're doing to cause all that ?

Crikey! Here I am months from the big '70, and I can count all my
"phut ... *KABLAM*"'s on one hand... and they were ALL in the lab, NOT
in the field, just great entertainment for my technicians... nothing
quite like the boss getting knocked off his lab stool to amuse the
troops ;-)
Mine are also in the lab. It usually happens when we try to push the
envelope a bit too much, when models don't jibe or when something else
breaks down and causes a huge reflection or things like that. I do a lot
of heavy duty pulse stuff where this is a normal part of life.

You are doing IC design. That's like signal corp versus a job in the
artillery. I did some chip designs as well but only a few and, you
guessed it, those are run hard along the kablam ridge. "But this will
electromigrate itself to death" ... "We have no real estate, got to do
it" ... "Yabbut, the design rules and all that" ..."It only needs to
live a few hours" ... "Oh".
Oops. It didn't.

They all do

Evidently not the ones that go "phut ... *KABLAM*", unless you're
really a closet pyro. ;-)

That's what my father thought when my first attempt at building a
kilowatt-size amplifier as a teenager showed some "sub-optimal"
behavior. I was blissfully unaware that even large electrolytic
capacitors have things like ESR and ripple current limits. Phssssoooosh
..... cap took off like a Saturn V, left a crater in the ceiling plaster
and a smolder hole in the carpet.

What I meant with *KABLAM* are experiments in the lab. The more you can
model beforehand the less likely it is that you blow through a case of
$250 RF transistors. This is why I prefer devices that come with SPICE
models. Because most of my RF designs are not run-of-the-mills benign
amplifiers at all.

 

[Joerg]

Jim Thompson wrote:
Jim Thompson wrote:
Charlie E. wrote:
[snip]
Yes, Jim, I think I sent that to you back in the day. But, you have
to be careful. It really does what is in effect an inverse FFT of the
Sparams, so it doesn't include any of the really important data you
need to do a good spice simulation when you are concerned more with
transient response.
That's exactly the point, especially with LDMOS. When a big old fat one
goes phut ... *KABLAM* it's mucho Dolares down the drain. Not the best
way to make friends at a new client.


... IBIS models are a 'little' better, but they are
also very behavioral and I was always interested in the little
'gotchas' that following them too closely led to.

Charlie
Joerg, You have way too much "phut ... *KABLAM*" in your life! What
is it you're doing to cause all that ?

Crikey! Here I am months from the big '70, and I can count all my
"phut ... *KABLAM*"'s on one hand... and they were ALL in the lab, NOT
in the field, just great entertainment for my technicians... nothing
quite like the boss getting knocked off his lab stool to amuse the
troops ;-)
Mine are also in the lab. It usually happens when we try to push the
envelope a bit too much, when models don't jibe or when something else
breaks down and causes a huge reflection or things like that. I do a lot
of heavy duty pulse stuff where this is a normal part of life.

You are doing IC design. That's like signal corp versus a job in the
artillery.
What a pile of horse pucky. Who do you think did Hubble magnetic
support, a satellite spinner for objects as big as a car, and
automotive environment for years and years and years ?

Then why does the electronics in cars croak so often ... ?

<duck and run>
Only GM (Government Motors) and Mercedes, judging from local
observation ;-) ...

Wasn't it Ford who managed to place an ingnition controller hybrid or
something similar on top of the engine?

Yep, it was called a "carburetor". ;-)

I thought that was a rather
stupid thing to do. Probably the cause of issues like "doesn't start
when still warm".

That's the one.

The electrical failures in my Chrysler weren't truly electrical. They
had mounted the alternator on an aluminum strut. Now that was really stupid.

Chrysler's body didn't last long enough for the electronics to be
stressed.

There you've got a point. Mine had the right rear suspension coil pop
into the cabin after about 6 years. Pathetic. Never bought a Chrysler again.

Consult for the government. No worries at all.

My work comes mostly via word-of-mouth, very little government
connections except with one new client.

 

[JosephKK]

Jim Thompson wrote:

[...]

Young man, queuing up to be cancer-victim-Duane's replacement, is, of
all things, the maintenance shop manager for the Chandler Police
Department...

http://www.analog-innovations.com/SED/AllisonAtMarksShop.JPG

They ride Honda, not Harley? I've never seen police ride Japanese bikes
anywhere. But Folsom PD and the CHP use BMW.

Heck, i used to ride an ex-police Kawasaki myself. Common in the Far
west US.

 

[Joerg]

Jim Thompson wrote:

[...]

Young man, queuing up to be cancer-victim-Duane's replacement, is, of
all things, the maintenance shop manager for the Chandler Police
Department...

http://www.analog-innovations.com/SED/AllisonAtMarksShop.JPG

They ride Honda, not Harley? I've never seen police ride Japanese bikes
anywhere. But Folsom PD and the CHP use BMW.

Heck, i used to ride an ex-police Kawasaki myself. Common in the Far
west US.

Kind of unusual, considering that they typically never buy foreign
brands for their cruisers. Although I think L.A. just started with
electric Mini-Coopers but only for the volunteer force.

 

[JosephKK]

Jim Thompson wrote:

[...]

Young man, queuing up to be cancer-victim-Duane's replacement, is, of
all things, the maintenance shop manager for the Chandler Police
Department...

http://www.analog-innovations.com/SED/AllisonAtMarksShop.JPG

They ride Honda, not Harley? I've never seen police ride Japanese bikes
anywhere. But Folsom PD and the CHP use BMW.

Heck, i used to ride an ex-police Kawasaki myself. Common in the Far
west US.

Kind of unusual, considering that they typically never buy foreign
brands for their cruisers. Although I think L.A. just started with
electric Mini-Coopers but only for the volunteer force.

BMW, Honda, and Motoguzzi seem to be the current most common for MC
patrol vehicles. There are some HD, Suzuki, Yamaha and other brands.
Kawasaki still seem to be used for MC interceptors.

 

[Fred Abse]

-snip=

I'd never, ever do that.

That's just your innate Teutonic politeness showing through, Joerg.
Embrace a little of the redneck culture, it can be very satisfying ;-)

 

[Joerg]

Nah, my religious beliefs tell me not to ;-)

Hmmmmm? I always thought my urges to trash ignorami were _because_
some of my heritage _is_ Teutonic ;-)

Thompson? Teutonic?

But yeah, Teutons used to have a reputation for being rude, among
Romans. Instead of proper battle planning Hermann's guys just got drunk
before a fight and ran at the Romans all hollering and fearless.
Ultimately the Romans high-tailed it ;-)