SWCADIII 555 model unrealistic?

[Spehro Pefhany]

On Fri, 26 Mar 2004 15:35:02 GMT, Spehro Pefhany
<speffSNIP@interlogDOTyou.knowwhat> wrote:


Sorry, wrong newsgroup for the binaries! mea culpa.

Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

 

[Mike Engelhardt]

Terry,

The other 555 is a transistor implementation in the file
./examples/Educational/NE555.asc. That one works rather like
a bipolar 555. You can see all the little glitches while it
runs.

OK, that certainly looks complex enough to be realistic! But how do I
set about using it in practice please, just as if it was another 555
model?

It's an actual transistor-level schematic of a 555. The easiest
thing to do would be decorate the schematic with the parts you want.
You'd even then be able to probe the inside of the IC. This is the
approach I recommend for you for now.

In CircuitMaker I'm familiar with making a new model by choosing an
appropriate symbol (such as an 8-pin DIP IC rectangle), adding
internal circuitry (such as your detailed 555 model), and saving as a
new part. Is there an equivalent approach in SWCADIII please?

Yes, you can do that do. There you could do basically this:
1. delete the external components from the 555 schematic.
2. label the pins as I/O ports
3. make a symbol with the same base name as the 555 schematic
and pin names that correspond to the port names
4. Place this symbol on a higher level schematic and decorate
it with the external parts there.
If you use this hierarchal schematic approach, start with all
files in the same directory. That will be less confusing.

Alternatively, you can library the 555 schematic's netlist as a
subcircuit and the write a symbol that automatically includes
this subcircuit on any schematic that uses the symbol.

For either of these techniques, you would want to read the help
sections on schematic capture.

--Mike

 

[Mike Engelhardt]

Terry,

Mike: I suggest a name change. 'NE555' is misleading. (That's
the Signetics, now Philips chip. How about something like '555'
or '555Ideal'?

I like keeping the name NE555 out of respect for the original,
but we've changed the symbol's description to "An Idealized 555
timer model" for furture releases. This is the description you see
in the "Select Component Symbol" dialog.

--Mike

 

[Mike Engelhardt]

Chuck, Kevin:

Actually we are very lucky. LT used to provide this
spice only for use with their switching regulator chips.
It was a very kindly act of generosity that allows you
to use it as a full featured spice emulator... for free,
no less.

Complete Nonsense. It was not an act of kindness or generosity
in any way whatsoever. It was a sound, well thought out business
decision. As Mike has already pointed out, it has probably led
to millions of dollars of increased sales for LT components.

Thanks, I like to think it was a well thought out business
decision. But there were at least two aspects of releasing
SwCADIII as an uncrippled SPICE that were discussed that may
or may not overlap with kindness and generosity. One is that
it didn't hurt Linear to release it as being more useful. That
was a 'gift' that didn't cost anything. It wasn't really known
if it would be appreciated or not, so on the non-commercial side
of life, it is nice to hear that LTspice is appreciated. The
other thing is that there's a tendency of hardware people to
dislike CAD houses. It was explicitly discussed as a good thing
for humanity if a better SPICE program was available for free
than what CAD houses try to sell -- just in the interest of
putting the CAD houses on notice.

For Kevin, you have this incredibly cold view of business. Maybe
you're just putting it on to try to look smart. Sure, there's a
fiduciary responsibility to a company's share holders to turn a
profit. At a company like Linear, that is felt all the way down
to the individual contributor(So, OK, I think Linear's a great
company). People making decisions have to make them without being
able to predict the future or know all the facts. In the process
of hedging all this ignorance, people chose how they live and what
morals are involved in the decisions they make and that goes into
business too. There's a human side for people in business making
business decisions that can include kindness and compassion.
LTspice doesn't have to be a free unlimited SPICE to fulfill its
role in helping to sell billions of dollars of SMPS products.
That's the bottom line.

--Mike

 

[Tam/WB2TT]

Plus you get a free and completely useful schematic entry program.

Tam

 

[Tim Shoppa]

Terry Pinnell <terrypin@dial.pipex.com> wrote in message news:<s8r6609ih2eond95bnvtll3fvlt3gnrv48@4ax.com>...

Mike: I suggest a name change. 'NE555' is misleading. (That's the
Signetics, now Philips chip. How about something like '555' or
'555Ideal'?

All models are unrealistic or idealized at some level. Most real
555's briefly short Vcc to Gnd whenever they switch, but I've yet to see
this in a model.

Different manufacturer's 555's actually can vary quite a bit in terms
of output impedance. I still have a few hundred signetics NE555's from the
early 70's should you want to test against the real deal

Tim.

 

[Terry Pinnell]

"Mike Engelhardt" <pmte@concentric.net> wrote:

Terry,

Mike: I suggest a name change. 'NE555' is misleading. (That's
the Signetics, now Philips chip. How about something like '555'
or '555Ideal'?

I like keeping the name NE555 out of respect for the original,
but we've changed the symbol's description to "An Idealized 555
timer model" for furture releases. This is the description you see
in the "Select Component Symbol" dialog.

Fair enough, thanks.

--
Terry Pinnell
Hobbyist, West Sussex, UK

 

[John Woodgate]

I read in sci.electronics.design that Mike Engelhardt
<pmte@concentric.net> wrote (in <c41nas$3nv@dispatch.concentric.net&gt
about 'SWCADIII 555 model unrealistic?', on Fri, 26 Mar 2004:

For Kevin, you have this incredibly cold view of business.

Kevin has a reason for being cheesed off about the temporal crumbling
characteristics of cookies, if you remember. He'd just started charging
for SuperSpice when your freebie hit the fan.
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

 

[Rene Tschaggelar]

Chuck Harris wrote:

Kevin Aylward wrote:

Chuck Harris wrote:

Hi Terry,

Actually we are very lucky. LT used to provide this spice only
for use with their switching regulator chips. It was a very kindly
act of generosity that allows you to use it as a full featured spice
emulator... for free, no less.



Complete Nonsense. It was not an act of kindness or generosity in any
way whatsoever. It was a sound, well thought out business decision. As
Mike has already pointed out, it has probably led to millions of dollars
of increased sales for LT components.

No one dose nought for nought in this universe. Companies simply don't
do things to be nice. http://www.anasoft.co.uk/replicators/index.html


Perhaps, but they could have done like Actel, Xilinx, Altera, Microchip,
... and charged large bucks for the tools that were necessary to use
their chips.

Were necessary ?
I never used a spice tool despite the fairly diverse variety of chips
I have on stock. Why would you simulate a 555, it does as told.

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

 

[Jim Thompson]

On Fri, 26 Mar 2004 21:34:12 +0100, Rene Tschaggelar <none@none.net>
wrote:

[snip]

I never used a spice tool despite the fairly diverse variety of chips
I have on stock. Why would you simulate a 555, it does as told.

Rene

You don't do very complex designs do you?

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

Throughout the history of this great country there have actually
been people of only two political persuasions: fighters and cowards.
WE MUST NOT LET THE LATTER PREVAIL IN THE NEXT ELECTION!

 

[John Woodgate]

I read in sci.electronics.design that Rene Tschaggelar <none@none.net>
wrote (in <406493e5$0$713$5402220f@news.sunrise.ch&gt about 'SWCADIII 555
model unrealistic?', on Fri, 26 Mar 2004:

Why would you simulate a 555, it does as told.

Not if you tell it to produce a 10 ps pulse or a 1-week pulse, or drive
a 1 ohm load from a 12 V supply. But the simulation quite possibly will!
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

 

[John Woodgate]

I read in sci.electronics.design that Mike Engelhardt
<pmte@concentric.net> wrote (in <c425lg$3o3@dispatch.concentric.net&gt
about 'SWCADIII 555 model unrealistic?', on Fri, 26 Mar 2004:

Linear has been giving away SMPS design software for about 15 years.
The current, unlimited, general-purpose SPICE version, LTspice/SwCADIII
based on a SPICE engine I wrote, was first released in 1998.

That's why I said 'hit the fan' instead of 'released' or anything
definite like that.

Put it like this, the first I saw (but possibly not the first mention)
about SwCADIII on this NG was just after KA announced the pay-for
version of SS.
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

 

[Kevin Aylward]

Mike Engelhardt wrote:

Chuck, Kevin:

Actually we are very lucky. LT used to provide this
spice only for use with their switching regulator chips.
It was a very kindly act of generosity that allows you
to use it as a full featured spice emulator... for free,
no less.

Complete Nonsense. It was not an act of kindness or generosity
in any way whatsoever. It was a sound, well thought out business
decision. As Mike has already pointed out, it has probably led
to millions of dollars of increased sales for LT components.

Thanks, I like to think it was a well thought out business
decision.

It is, as apparently, other competitors don't seem to have appreciated
what an edge having their companies name on the desk top every day is.
Its an excellent marketing tool.

Well thought out can actually be a matter of only 5 minutes thought.

But there were at least two aspects of releasing
SwCADIII as an uncrippled SPICE that were discussed that may
or may not overlap with kindness and generosity. One is that
it didn't hurt Linear to release it as being more useful. That
was a 'gift' that didn't cost anything.

I agree, that part of it was already there, however, it still cost
something.

It wasn't really known
if it would be appreciated or not, so on the non-commercial side
of life, it is nice to hear that LTspice is appreciated. The
other thing is that there's a tendency of hardware people to
dislike CAD houses. It was explicitly discussed as a good thing
for humanity if a better SPICE program was available for free
than what CAD houses try to sell

I am sure, many if not most, are not as honest with themselves as they
like to think they are.

-- just in the interest of
putting the CAD houses on notice.

For Kevin, you have this incredibly cold view of business.

Indeed I do. As I do of life in general. Its what the facts dictate.

Maybe
you're just putting it on to try to look smart.

Not at all. Have you not yet really grasped my view of life, e.g. my
aforementioned Mean Meme-Gene Darwinian Machine papers. I don't consider
it debatable. Evolution is a fact.

Sure, there's a
fiduciary responsibility to a company's share holders to turn a
profit.

Indeed.

At a company like Linear, that is felt all the way down
to the individual contributor(So, OK, I think Linear's a great
company). People making decisions have to make them without being
able to predict the future or know all the facts. In the process
of hedging all this ignorance, people chose how they live and what
morals are involved in the decisions they make and that goes into
business too. There's a human side for people in business making
business decisions that can include kindness and compassion.

It is much more subtle than this. Evolution demands that we behave in
certain ways. We only feel good about helping others because evolution
has dictated that that is in our best interests. The fact that we may
not be always be consciously aware of such programming, doesn't change
anything. Life is the way it is. Cold. As I noted, most simply cant
accept that what they do is selfish.
http://www.anasoft.co.uk/replicators/psychology.html

I would like it to be differernt, but it isnt.

Kevin Aylward
salesEXTRACT@anasoft.co.uk
http://www.anasoft.co.uk
SuperSpice, a very affordable Mixed-Mode
Windows Simulator with Schematic Capture,
Waveform Display, FFT's and Filter Design.

"quotes with no meaning, are meaningless" - Kevin Aylward.

 

[Frank Bemelman]

"John Woodgate" <jmw@jmwa.demon.contraspam.yuk> schreef in bericht
news:tao+w5FQ1JZAFwHF@jmwa.demon.co.uk...

I read in sci.electronics.design that Rene Tschaggelar <none@none.net
wrote (in <406493e5$0$713$5402220f@news.sunrise.ch&gt about 'SWCADIII 555
model unrealistic?', on Fri, 26 Mar 2004:

Why would you simulate a 555, it does as told.

Not if you tell it to produce a 10 ps pulse or a 1-week pulse, or drive
a 1 ohm load from a 12 V supply. But the simulation quite possibly will!

I don't think it will simulate very satisfying when trying to get a 10ps
pulse out of it, or trying to driving a 1 ohm load. It may simulate nicely
for a 1-week pulse, but that's not the 555 (model) to blame.

--
Thanks, Frank.
(remove 'x' and 'invalid' when replying by email)

 

[Kevin Aylward]

John Woodgate wrote:

I read in sci.electronics.design that Mike Engelhardt
pmte@concentric.net> wrote (in <c425lg$3o3@dispatch.concentric.net&gt
about 'SWCADIII 555 model unrealistic?', on Fri, 26 Mar 2004:

Linear has been giving away SMPS design software for about 15 years.
The current, unlimited, general-purpose SPICE version,
LTspice/SwCADIII based on a SPICE engine I wrote, was first released
in 1998.

That's why I said 'hit the fan' instead of 'released' or anything
definite like that.

Put it like this, the first I saw (but possibly not the first mention)
about SwCADIII on this NG was just after KA announced the pay-for
version of SS.

But as I keep pointing out, the demo allows 30 top level blocks times 25
one level deep schematics, giving 750 real components.

Kevin Aylward
salesEXTRACT@anasoft.co.uk
http://www.anasoft.co.uk
SuperSpice, a very affordable Mixed-Mode
Windows Simulator with Schematic Capture,
Waveform Display, FFT's and Filter Design.

"quotes with no meaning, are meaningless" - Kevin Aylward.

 

[Kevin Aylward]

John Woodgate wrote:

I read in sci.electronics.design that Mike Engelhardt
pmte@concentric.net> wrote (in <c41nas$3nv@dispatch.concentric.net&gt
about 'SWCADIII 555 model unrealistic?', on Fri, 26 Mar 2004:

For Kevin, you have this incredibly cold view of business.

Kevin has a reason for being cheesed off about the temporal crumbling
characteristics of cookies, if you remember. He'd just started
charging for SuperSpice when your freebie hit the fan.

Don't forget, I didn't write SS to make money. I simply couldn't afford
to spend $3000 for PSpice. I felt that I would learn a doing it, and I
have. Making some drinking money is just a bonus. I have an amazingly
amount of selfish self satisfaction by completing that project.

Kevin Aylward
salesEXTRACT@anasoft.co.uk
http://www.anasoft.co.uk
SuperSpice, a very affordable Mixed-Mode
Windows Simulator with Schematic Capture,
Waveform Display, FFT's and Filter Design.

"quotes with no meaning, are meaningless" - Kevin Aylward.

 

[Chuck Harris]

Rene Tschaggelar wrote:

Chuck Harris wrote:



Perhaps, but they could have done like Actel, Xilinx, Altera, Microchip,
... and charged large bucks for the tools that were necessary to use
their chips.


Were necessary ?
I never used a spice tool despite the fairly diverse variety of chips
I have on stock. Why would you simulate a 555, it does as told.

Rene

Admit it Rene, you don't know what kind of chips Actel, Xilinx, ...
make. Right?

-Chuck Harris

FIY, They make programmable logic devices. You cannot do zip without
their tools. Each has made the fitters for their chips proprietary, and
have lawyers who will vigorously beat you to a pulp if you try to write
your own fitter. (Not microchip ;-)

 

[Chaos Master]

Somebody hiding from the police, using the fake name of "maxfoo" wrote:

On Fri, 26 Mar 2004 15:41:55 GMT, Spehro Pefhany
speffSNIP@interlogDOTyou.knowwhat> wrote:

On Fri, 26 Mar 2004 15:35:02 GMT, Spehro Pefhany
speffSNIP@interlogDOTyou.knowwhat> wrote:


Sorry, wrong newsgroup for the binaries! mea culpa.

Best regards,
Spehro Pefhany

Sorry does not cut it dude,
DarkMatter will be all over your shit now.

Shit happens, ya know.
But DarkMatter wants that shit.

--
_____ ___ Chaos MasterŽ
| | Posting from Brazil
| | MSN: wizard_of_yendor at hotmail.com
___|_____| irc.brasnet.org #XLinuxNews #POA

 

[Rene Tschaggelar]

Chuck Harris wrote:

Rene Tschaggelar wrote:

Chuck Harris wrote:



Perhaps, but they could have done like Actel, Xilinx, Altera, Microchip,
... and charged large bucks for the tools that were necessary to use
their chips.

Were necessary ?
I never used a spice tool despite the fairly diverse variety of chips
I have on stock. Why would you simulate a 555, it does as told.


Admit it Rene, you don't know what kind of chips Actel, Xilinx, ...
make. Right?

FIY, They make programmable logic devices. You cannot do zip without
their tools. Each has made the fitters for their chips proprietary, and
have lawyers who will vigorously beat you to a pulp if you try to write
your own fitter. (Not microchip ;-)

Thanks Chuck,
I actually do Altera designs. Yes, the MaxPlus2 or Quartus is
necessary. However, they not only do the simuation, they also do the
routing and the programming. Just for the schematics, they wouldn't be
necessary. I hardly ever fail with my schematic entry.
I also did a few switchmode supplies, they can be build without simulation.

Rene

 

[Rene Tschaggelar]

Jim Thompson wrote:

On Fri, 26 Mar 2004 21:34:12 +0100, Rene Tschaggelar <none@none.net
wrote:

[snip]

I never used a spice tool despite the fairly diverse variety of chips
I have on stock. Why would you simulate a 555, it does as told.


You don't do very complex designs do you?

That depends. A bit more complex than 3 transistors used to inflate a
ballon, yes. By other standards perhaps not. Never mind.
Till now I was able to shift compexity into the software. And the
hardware did what it had to do, except for an error here or there.


Rene