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SuperSpice and new component

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oran...@mail.ru

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Mar 16, 2005, 7:18:37 AM3/16/05
to
I need to analyse VERY simple circuit with SuperSpice (or should I use
some other program?). Schematics has some resistors and 'special type'
of (coax)amplifiers. All that I know about those amplifiers is that
their U*I=22,5Watt, but that should be all that I need. It is connected
to power supply =63V DC.
I want to know the (DC)current that those amplifiers are using and
their voltage.

How do I add that type of amplifiers to SuperSpice component database?

I do not need any complex analysis, just DC voltages and currents. I
have used Derive for (numerical) solving system of nonlinear equations,
but SuperSpice should be easier for modifying schematics..etc?

Kevin Aylward

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Mar 16, 2005, 9:19:52 AM3/16/05
to
oran...@mail.ru wrote:
> I need to analyse VERY simple circuit with SuperSpice

You can always email me direct. Support is all free.

(or should I use
> some other program?).

No:-)

> Schematics has some resistors and 'special type'
> of (coax)amplifiers. All that I know about those amplifiers is that
> their U*I=22,5Watt, but that should be all that I need.

This don't seem to mean much. Amps have all sorts of specs, like gain,
bandwidth, noise, slew rate etc.

>It is
> connected to power supply =63V DC.
> I want to know the (DC)current that those amplifiers are using and
> their voltage.
>
> How do I add that type of amplifiers to SuperSpice component database?

I presume you mean the specific amp model which is a ".subckt".
".subckt" models are placed in library text files, usually with the
extension .lib. You need to find out what the amp model is.

Adding a file with models is just a matter of drag-dropping the file
from windows explorer to the SS main window. You aslo ope existing files
and past in the model text

When you try and place the ".subckt" it will want to be attached to a
symbol. The GUI will guide you through selecting an existing symbol, or
you can create a block symbol automatically, or draw one from scratch
using the symbol editor.

>
> I do not need any complex analysis, just DC voltages and currents. I
> have used Derive for (numerical) solving system of nonlinear
> equations, but SuperSpice should be easier for modifying
> schematics..etc?

Yes it is. However, I need more specific info though to sort out your
problem. Your amp spec is pretty much meaningless.

Kevin Aylward
salesE...@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.


oran...@mail.ru

unread,
Mar 17, 2005, 8:22:33 AM3/17/05
to
>> Schematics has some resistors and 'special type'
>> of (coax)amplifiers. All that I know about those amplifiers is that
>> their U*I=22,5Watt, but that should be all that I need.
>
> This don't seem to mean much. Amps have all sorts of specs, like
gain,
> bandwidth, noise, slew rate etc.

but I really don't need all that. When I try to solve it manually, I
write down Kirchhoffs rules and equations for componenets, use math
program for numerical solving of system and thats ALL.
I just want program to make it easier for me when for eg. removing one
resistor.
To me, (coax) amplifier is a 'strange' resistor with U=22/I. Its a
'black box' with two wires and I don't wanna know more about it. My
problem is
calculating ONLY power supply of amps, so it should be really simple
to solve it.

>>It is
>> connected to power supply =63V DC.
>> I want to know the (DC)current that those amplifiers are using and
>> their voltage.
>>
>> How do I add that type of amplifiers to SuperSpice component
database?
>
> I presume you mean the specific amp model which is a ".subckt".
> ".subckt" models are placed in library text files, usually with the
> extension .lib. You need to find out what the amp model is.

yes, (but its not really an 'amp' to me, at least not now)

oran...@mail.ru

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Mar 17, 2005, 8:23:51 AM3/17/05
to
you once said:

'To construct a non-linear resistor, one can set up a voltage dependent
current source as a non-linear function of its own terminal voltage.
I've never tried it, but believe a behavioral source's describing
function can include frequency. But even if you could, why would you
wish to model a non realizable component?'


What I need is to 'construct' a nonlinear resistor that has: I=P/U
(P=const.=22.5Watt)

how do I do it?

Kevin Aylward

unread,
Mar 17, 2005, 9:42:06 AM3/17/05
to
oran...@mail.ru wrote:
>>> Schematics has some resistors and 'special type'
>>> of (coax)amplifiers. All that I know about those amplifiers is that
>>> their U*I=22,5Watt, but that should be all that I need.
>>
>> This don't seem to mean much. Amps have all sorts of specs, like
>> gain, bandwidth, noise, slew rate etc.
>
> but I really don't need all that. When I try to solve it manually, I
> write down Kirchhoffs rules and equations for componenets, use math
> program for numerical solving of system and thats ALL.
> I just want program to make it easier for me when for eg. removing one
> resistor.
> To me, (coax) amplifier is a 'strange' resistor with U=22/I.


An amplifier is not a resister. The problem here, is that you are
essentially, talking gibberish. "U" means nothing, other then as a
referance desigater.

>Its a
> 'black box' with two wires and I don't wanna know more about it.

But *we* need to know what your talking about to help you. You are using
notation that means, essentially, nothing in electronics.

> problem is
> calculating ONLY power supply of amps, so it should be really simple
> to solve it.

Probably is, if you can tell us what you are actualy trying to do.

Do you mean somting to do with

V=IR

or V=P/I

Until you formulate you problem correctly, or explain in more detail
what you are trying to do so we can formulate it for you, no one can
help you.


Kevin Aylward
informati...@anasoft.co.uk

Kevin Aylward

unread,
Mar 17, 2005, 9:42:03 AM3/17/05
to

Until you tell us what "U" is, we don't know. Do you want to confirm it
might be "V", for voltage?

Genome

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Mar 17, 2005, 12:33:38 PM3/17/05
to

"Kevin Aylward" <salesE...@anasoft.co.uk> wrote in message
news:cgXZd.68825$Bk7....@fe1.news.blueyonder.co.uk...
> oran...@mail.ru wrote:

Oi, I happened to be in my registry today. I had a look at your software
once and then uninstalled it. What's that anasoft/superspice crap doing in
my registry?

DNA


oran...@mail.ru

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Mar 17, 2005, 2:57:56 PM3/17/05
to
of course it means the same as V.. I've been using symbol U as voltage
for years in school.. so I thought everyone else used it too, my
mistake., sorry

The 'amplifier' has constant power: V*I=22.5Watt, that is it, nothing
more..

I have been trying to use your users guide and part that describes:
3.2.3. Non-linear Dependent Sources
but as you can see I'm a total newbie and need help badly..

Jim Thompson

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Mar 17, 2005, 3:10:08 PM3/17/05
to

Just use a G source (behavioral), where G = W/V (W=22.5)

I don't know SuperSpice, but that expression _might_ cause convergence
issues. If so try:

G = W/(abs(V)+0.001)

to avoid a divide by zero.

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

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

Helmut Sennewald

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Mar 17, 2005, 3:51:32 PM3/17/05
to
<oran...@mail.ru> schrieb im Newsbeitrag
news:1111089476....@f14g2000cwb.googlegroups.com...


Hello orange,
this is an example how you would write it in a netlist.
B1 is a behaviorial current source. The current is
I = const/actual_voltage .

B1 a 0 I=22.5/V(a)

What you see above is SPICE instruction line.
It can be also the result of a schematic containing a B-source.
I have attached a schematic file from another SPICE program.
It's LTspice. This example sweeps the voltage from 20V to 60V.
You can download LTspice with this link.
http://ltspice.linear.com/software/swcadiii.exe

There are many other SPICE programs around, but not all have
behavioral sources.

Best Regards,
Helmut

This is the schematic file "test.asc".

Version 4
SHEET 1 880 680
WIRE 32 208 32 160
WIRE 32 336 32 288
WIRE 32 368 32 336
WIRE 208 160 32 160
WIRE 208 208 208 160
WIRE 208 336 32 336
WIRE 208 336 208 288
FLAG 32 368 0
FLAG 208 160 a
SYMBOL voltage 32 192 R0
SYMATTR InstName V1
SYMATTR Value 63
SYMBOL bi 208 208 R0
SYMATTR InstName B1
SYMATTR Value I=22.5/V(a)
TEXT 32 80 Left 0 !.dc V1 20 100 1
TEXT 40 24 Left 0 ;I = P / V


Kevin Aylward

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Mar 18, 2005, 2:49:18 AM3/18/05
to

Well, it just stays there. It don't do anything. Its completely passive.
You can just delete the whole lot if you want. I did have a go once at
improving the delete on uninstall, but it got to be a bit of pain with
the install/uninstall program I use.

Kevin Aylward
informati...@anasoft.co.uk

oran...@mail.ru

unread,
Mar 18, 2005, 8:10:22 AM3/18/05
to
you said:
>Hello orange,
>this is an example how you would write it in a netlist.
>B1 is a behaviorial current source. The current is
>I = const/actual_voltage .

>B1 a 0 I=22.5/V(a)

>What you see above is SPICE instruction line.

yes, that is what i need, but how to do it in super spice?

I have tried modifying 'functional' component named COS_XN like this:

.SUBCKT COS_XN _ssi_pin0 1
* _SS_Symbol [C:\Program
Files\AnaSoft\SuperSpice\system\SchematicBlocks.ssm] [2PinBlock]
B1 _ssi_pin0 1 I=22/(V(_ssi_pin0,1))
.ENDS

but it doesn't work. Please tell me how to make it work.


BTW, does ltspice have nice and greatlooking GUI like superspice? Can I
easily draw schematics in it? I don't wanna type in node numbers and
elements like in old spice, ever.

oran...@mail.ru

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Mar 18, 2005, 12:22:42 PM3/18/05
to
it works!! :))
where do I set how many digits of precision is needed?

Kevin Aylward

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Mar 19, 2005, 2:58:11 AM3/19/05
to
oran...@mail.ru wrote:
> it works!! :))
> where do I set how many digits of precision is needed?

Not sure what you mean by this. The calculation itself always uses the
full range that the compiler supports, which is something like 12 digits
of accuracy. This never need setting. You can change the number of
digits displayed by clicking on the graph and going to the Options/misc
tab. The default is usually quite adequate.

Mike Engelhardt

unread,
Mar 19, 2005, 11:58:47 AM3/19/05
to
orangeKDS,

> BTW, does ltspice [...]Can I easily draw schematics in


> it? I don't wanna type in node numbers and elements
> like in old spice, ever.

LTspice had integrated schematic capture. It also lets
you add SPICE directives on the schematic and has dialog
boxes that let you mix and match editing the SPICE
syntax in text or checking boxes on a dialog box. You
might want to check it out. More full licenses of
LTspice are distribed per day than, say, PSpice/Schematic/
Orcad does in a year.

--Mike


Jim Thompson

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Mar 19, 2005, 12:17:49 PM3/19/05
to
On Sat, 19 Mar 2005 16:58:47 GMT, "Mike Engelhardt" <nos...@spam.org>
wrote:

And Wimpows has even more licenses than LTSpice ;-)

Mike Engelhardt

unread,
Mar 19, 2005, 12:26:39 PM3/19/05
to
Jim,

> > More full licenses of LTspice are distributed per day than,


> > say, PSpice/Schematic/ Orcad does in a year.
>

> And Wimpows has even more licenses than LTSpice ;-)

Wrong-Horse-Thompson -- stuck in the wrong simulator
saddle again!

--Mike


Jim Thompson

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Mar 19, 2005, 12:47:56 PM3/19/05
to

Could be.

However one of my clients tried LTSpice on a *complex* BiCMOS circuit
and got spurious results, not matching actual performance like PSpice
did.

I suspect that your speed-up algorithms, just ducky for SMPS, can skip
over important stuff in other types of circuits.

Mike Engelhardt

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Mar 19, 2005, 1:11:13 PM3/19/05
to
Jim,

>>>> More full licenses of LTspice are distributed per day than,
>>>> say, PSpice/Schematic/ Orcad does in a year.
>>>
>>> And Wimpows has even more licenses than LTSpice ;-)
>>
>> Wrong-Horse-Thompson -- stuck in the wrong simulator
>> saddle again!
>

> Could be.
>
> However one of my clients tried LTSpice on a *complex* BiCMOS
> circuit and got spurious results, not matching actual
> performance like PSpice did.
>
> I suspect that your speed-up algorithms, just ducky for SMPS,
> can skip over important stuff in other types of circuits.

Nothing that speeds up the SMPS stuff would corrupt
the BiCMOS results. The SMPS stuff doesn't impact the
SPICE stuff, its a library of ABM, special devices,
and HDL's w/ some VerilogA-type extensions. Anyway,
people upgrade routinely from PSpice and hspice to
LTspice for it's speed, *accuracy*, and convergence
specifically in BiCMOS full-chip simulation. LTspice
was first a IC simulation tool and second a SMPS
tool. BTW, it now has a new data file format called
Fast Access that allows you to load waveforms from
full chip sims extremely fast, i.e., if you have a
5G file with 2K data traces the load time for a new
trace drops from 5min to 1sec with not one bit loss
of accuracy.

I'd have to see the circuit to tell what happened.
Please feel free to send the files I need to duplicate
the problem and I can tell you what the problem was.
Just to rub it in, last time you sent me a nelist,
LTspice gave the correct result and PSpice gave the
wrong one because it isn't as accurate at integrating
differential equations.

The most effective thing for me would be if you
first make sure you're using the current version(2.13x)
and see if the problem occurs both in the Normal
and Alternate solver(Tools=>Control Panel=>SPICE=>
Solver)

Regards,

--Mike


Jim Thompson

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Mar 19, 2005, 1:16:14 PM3/19/05
to
On Sat, 19 Mar 2005 18:11:13 GMT, "Mike Engelhardt"
<nos...@nospam.org> wrote:

>Jim,
[snip]


>
>I'd have to see the circuit to tell what happened.
>Please feel free to send the files I need to duplicate
>the problem and I can tell you what the problem was.
>Just to rub it in, last time you sent me a nelist,
>LTspice gave the correct result and PSpice gave the
>wrong one because it isn't as accurate at integrating
>differential equations.
>
>The most effective thing for me would be if you
>first make sure you're using the current version(2.13x)
>and see if the problem occurs both in the Normal
>and Alternate solver(Tools=>Control Panel=>SPICE=>
>Solver)
>
>Regards,
>
>--Mike
>

qrk/Mark, Could you send Mike the circuit? I don't recall now what
was involved.

ldg

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Mar 20, 2005, 1:03:24 PM3/20/05
to
On Sat, 19 Mar 2005 16:58:47 GMT, "Mike Engelhardt" <nos...@spam.org>
wrote:

>More full licenses of


>LTspice are distribed per day than, say, PSpice/Schematic/
>Orcad does in a year.


And more are deleted :-)

Actually, LTspice seems to be getting slightly better, but is a board
level simulator. If that's you're purpose, then fine. If you're
doing IC's, it will soon disappoint.

It still doesn't seem to be able to handle simple hspice models for
resistors and capacitors. (specified by w/l). These are simple
things, but not needed for board level work.

I haven't tried using a multiplier ( m=) for bipolars, but this didn't
seem to work when I tried it a while back in a bandgap. A multiplier
isn't in the LTspice documentation for bipolars, so it's really not
there anyway. Again, if you're not doing a lot of device level work
using bipolars, this isn't too much of a problem. There are many
things like this you run into when trying to use LTspice for IC's.

So LTspice is a board level simulator with nice graphics. There are
many undocumented features in LTspice that people have reverse
engineered, but a user shouldn't have to do that.

I looked at Simetrix recently and they can't do m= (mutipliers) on
capacitors, so LTspice has them beat there. They have a native linux
version though and that sure is tempting.

Both LTspice and Simetrix run well on my AMD 64 box under SuSE9.2.

Ltspice really does run well under wine. I was impressed. I didn't
do benchmarks, so have no way of knowing at this point how the extra
overhead might affect a long simulation. What impressed me most I
think was the ease with which this software loaded and ran. As a new
linux administrator (used unix for years), I've struggled with getting
other software to run. Loading LTspice was a joy in comparison. 64
bits? No problem.

I tried recently to get ECS/Synario/Cohesion/Lakers_AMS schematic
capture to run under SuSE9.2. It's libraries are dependent on Redhat
V3 and gets glibc errors under SuSE.

Smartspice won't even let you try their software if you tell them you
have anything besides Redhat V3. They don't support anything else.
End of story. They're nice about it though :-)

Looks like I chose the wrong distro for my linux box. I'm going to
have to switch over to Redhat since that's what the engineering
software companies seem to have standardized on. From what I
understand the different distros use the same libraries, but have
arranged them differently? If true it makes one wonder if the word
duh means anything to these folks. Then again, why is it some vendors
seem to be able to write distro independent software for linux and
while others can't?

Regards,
Larry


Mike Engelhardt

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Mar 20, 2005, 2:07:39 PM3/20/05
to
Larry,

> Actually, LTspice seems to be getting slightly better,
> but is a board level simulator. If that's you're purpose,
> then fine. If you're doing IC's, it will soon disappoint.
>
> It still doesn't seem to be able to handle simple hspice
> models for resistors and capacitors. (specified by w/l).
> These are simple things, but not needed for board level
> work.

I have people upgrading from hspice to LTspice to for IC
design. For accuracy.

--Mike


ldg

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Mar 20, 2005, 10:13:05 PM3/20/05
to

in your dreams. :-)

Jim Thompson

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Mar 20, 2005, 10:23:13 PM3/20/05
to

ldg, You harp about things that you know not about. LTSpice can run
ANY netlist... you're just too much the amateur to understand how.

If only Mike would make his simulation engine talk to my venerable old
MicroSim Schematics he'd likely have a convert.

ldg

unread,
Mar 21, 2005, 2:36:12 AM3/21/05
to
On Sun, 20 Mar 2005 20:23:13 -0700, Jim Dynamite
<thegr...@example.com> wrote:

>dg, You harp about things that you know not about. LTSpice can run
>ANY netlist... you're just too much the amateur to understand how.

Really? :-)

Didn't know I was harping. What things are you worried about? Just
the parts about devices?

I said:
o LTspice can't handle resistor and capacitors specified with w/l and
models. (It can actually run resistors this way with various error
messages, but it's undocumented.) You can use undocumented features
if you like. I usually choose not to.

I have run circuits in ltspice with resistors to use the graphics, but
always have checked the results with other simulators. I like using
multiple simulators anyway as a cross check so this isn't unusual. I
don't like seeing the error messages LTspice gives with these models.

Caps don't seem to work at all specified this way, but aren't supposed
to:

Syntax: Cnnn n1 n2 <capacitance> [ic=<value>]
+ [Rser=<value>] [Lser=<value>] [Rpar=<value>]

+ [Cpar=<value>] [m=<value>]
+ [RLshunt=<value>]

**********

LTSPICE test
*********************************************************
.model pp c cox=9e-04 capsw=2.5e-11 del=0.045e-6
+ tref=25 tc1=22e-6 tc2=0.0

*********************************************************

V1 1 0 pulse(0 5 5u 1n 1n 1)
R1 1 2 1e5
C1 2 0 5p m=1
R3 1 3 1e5
C3 3 0 PP W=33.33U L=33.33U M=5
*c3 3 0 1p m=5
.tran 1u 15u

.end

*********************************************************

Perhaps you can show me how to run this netlist in LTspice? It will
run in smartspice just fine. I guess it literally "runs" in
LTspice, but seems to give the wrong answer when the cap is specified
by w/l and uses a typical foundry model.

A lot of this is preference. I did my own layouts for years and now
hire others to do it. I've found it more accurate to design resistors
and capacitors myself rather than giving the layout person so much
leeway by specifying values. I also use the foundry specified models
for these devices during simulation.

I'd be interested in how a professional organizes their workflow. How
about teaching me a few things? As I recall you use the old Microsim
schematic capture for layout and simulate in pspice. Is this the
perfect solution (and we should all copy) or do you do this for some
other reason? Do you do your own layout? What tools do you use?

o No M= on Bipolars?

**********
Symbol Names: NPN, PNP, NPN2, PNP2

Syntax: Qxxx Collector Base Emitter [Substrate Node] model [area]
+ [off] [IC=<Vbe, Vce>] [temp=<T>]

**********

I don't see it in the documentation. It may by now be an undocumented
feature and I haven't tried this lately.

Again, you're free to draw as many parallel devices and work-arounds
as you like. I'm trying to avoid this.

Thanks for any professional advice :-)

Regards,
Larry


Helmut Sennewald

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Mar 21, 2005, 2:57:04 AM3/21/05
to
"ldg" <as...@hotmail.com> schrieb im Newsbeitrag
news:tqms31hmn7iup88oc...@4ax.com...


Hello Larry,
the multiplier for Q is now in the LTspice documentation and it's
implemeted.
I wonder why it is exactly the same text as you posted.


---- From the manual -------

Q. Bipolar transistor

Symbol Names: NPN, PNP, NPN2, PNP2

Syntax: Qxxx Collector Base Emitter [Substrate Node] model [area]
+ [off] [IC=<Vbe, Vce>] [temp=<T>]

---- End ----


To all here,
don't make personal attacks. It doesn't help the technical discussions.


Best Regards,
Helmut

PS: I am not an employee off Linear Technology.

Useful links:

LTspice/SwitcherCAD: www.linear.com

User group: http://groups.yahoo.com/group/LTspice/
I am one of the two moderators of this group.

Pera Mitic

unread,
Mar 21, 2005, 5:22:38 AM3/21/05
to
On Sat, 19 Mar 2005 07:58:11 GMT, "Kevin Aylward"
<salesE...@anasoft.co.uk> wrote:

>oran...@mail.ru wrote:
>> it works!! :))
>> where do I set how many digits of precision is needed?
>
>Not sure what you mean by this. The calculation itself always uses the
>full range that the compiler supports, which is something like 12 digits
>of accuracy. This never need setting. You can change the number of
>digits displayed by clicking on the graph and going to the Options/misc
>tab. The default is usually quite adequate.
>

I see, ok

but i have another problem now: convergence :((
I have found in manual that you could set initial guess for some
voltages and currents that helps iteration process.

>.NODESET: Specify Initial Node Voltage Guesses
> 4.2.1. .NODESET: Specify Initial Node Voltage Guesses
> General form:
> .NODESET V(NODNUM)=VAL V(NODNUM)=VAL ...

where do I enter this in superspice?
(I'm hoping that guessing will help iteration)

I've got 19 of those nonlinear components we talked about (I=const/V).
With smaller circuits (12 of them), everything is ok

All I need is operating point analysis and for relativelty large
voltages (~30V) and currents (~1A)

Pera Mitic

unread,
Mar 21, 2005, 6:16:51 AM3/21/05
to
On Mon, 21 Mar 2005 11:22:38 +0100, Pera Mitic <oran...@mail.ru>
wrote:

I made a mistake, there are 29 of them. When I remove just 3, it
works. Maybe that means its not possible in reality to supply all of
them?

I need one more thing (less important): is it possible somehow to set
values of all resistors to =const*R
?
(I have to calculate resistors, for eg. R1=150m *0.00528 Ohm/m
it would be a lot easier to simply enter meters and let your program
calculate resistance)


--
Qmnon fgr ebg-binyv

Ken Smith

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Mar 21, 2005, 10:07:56 AM3/21/05
to
In article <9rbr3156lgmhjsde2...@4ax.com>,
ldg <as...@hotmail.com> wrote:
[...]

>Ltspice really does run well under wine. I was impressed. I didn't
>do benchmarks, so have no way of knowing at this point how the extra
>overhead might affect a long simulation.

I think you will find that the extra overhead of running it under Windows
(at least Win98) makes it run only a little slower than it does using
wine. Is this what you mean?


[...]


>arranged them differently? If true it makes one wonder if the word
>duh means anything to these folks. Then again, why is it some vendors
>seem to be able to write distro independent software for linux and
>while others can't?

Some companies have good programmers and others don't. In some cases, it
isn't that the software will not work just fine on some other system, it
just that the maker only tests it on one version and makes their install
script test for that specific version.


I use SuSE to run "dosemu" to run the DOS Orcad. I had troubles with DOS
orcad running dos windows on Windows machines. So far there has been no
problem under dosemu. Unlike windows, xdosemu allows the DOS window to be
resized etc.

--
--
kens...@rahul.net forging knowledge

ldg

unread,
Mar 21, 2005, 10:19:12 AM3/21/05
to
On Mon, 21 Mar 2005 08:57:04 +0100, "Helmut Sennewald"
<HelmutS...@t-online.de> wrote:

>Hello Larry,
>the multiplier for Q is now in the LTspice documentation and it's
>implemeted.
>I wonder why it is exactly the same text as you posted.
>
>
>---- From the manual -------
>
>Q. Bipolar transistor
>
>Symbol Names: NPN, PNP, NPN2, PNP2
>
>Syntax: Qxxx Collector Base Emitter [Substrate Node] model [area]
> + [off] [IC=<Vbe, Vce>] [temp=<T>]

Thanks Helmut,

This is very useful to know. You say it is in the LTspice
documentation, but where? I know I'm needing better glasses, but I'm
having trouble finding the [M=<M>] in the above text. Is there other
documentation posted for this simulator other than the help file?

Like I said, LTspice keeps getting better :-)

Regards,
Larry

Jim Thompson

unread,
Mar 21, 2005, 10:13:40 AM3/21/05
to
On Sun, 20 Mar 2005 23:36:12 -0800, ldg <as...@hotmail.com> wrote:

>On Sun, 20 Mar 2005 20:23:13 -0700, Jim Dynamite
><thegr...@example.com> wrote:
>
>>dg, You harp about things that you know not about. LTSpice can run
>>ANY netlist... you're just too much the amateur to understand how.
>
>Really? :-)
>
>Didn't know I was harping. What things are you worried about? Just
>the parts about devices?
>
>I said:
>o LTspice can't handle resistor and capacitors specified with w/l and
>models. (It can actually run resistors this way with various error
>messages, but it's undocumented.) You can use undocumented features
>if you like. I usually choose not to.

Sure it can. In most Spices, it's done with subcircuits...

xR node1 node2 <stray nodes> ModelName Params: L=100u W=2u M=4



>
>I have run circuits in ltspice with resistors to use the graphics, but
>always have checked the results with other simulators. I like using
>multiple simulators anyway as a cross check so this isn't unusual. I
>don't like seeing the error messages LTspice gives with these models.

HSpice and "Smart"Spice tend to run NON-SPICE-STANDARD notation just
to be ass-holes and thwart portability.

But my particular schematic capture can write out netlists in multiple
templates, so I can presently write in PSpice, LVS (for any layout
editor) and SmartSpice/HSpice formats.

There IS an issue with computational notation, {...} or '...' , but
that was solved this weekend (see below).

>
>Caps don't seem to work at all specified this way, but aren't supposed
>to:
>
>Syntax: Cnnn n1 n2 <capacitance> [ic=<value>]
> + [Rser=<value>] [Lser=<value>] [Rpar=<value>]
>
> + [Cpar=<value>] [m=<value>]
> + [RLshunt=<value>]
>

Done the same way as R's...

xC node1 node2 <stray nodes> ModelName Params: L=100u W=20u (Some
nutcases use an M here, I don't, it's confusing... for segmented R's I
may adopt "S")

>**********
>
>LTSPICE test
>*********************************************************
>.model pp c cox=9e-04 capsw=2.5e-11 del=0.045e-6
>+ tref=25 tc1=22e-6 tc2=0.0
>
>*********************************************************
>
>V1 1 0 pulse(0 5 5u 1n 1n 1)
>R1 1 2 1e5
>C1 2 0 5p m=1
>R3 1 3 1e5
>C3 3 0 PP W=33.33U L=33.33U M=5
>*c3 3 0 1p m=5
>.tran 1u 15u
>
>.end
>
>*********************************************************
>
>Perhaps you can show me how to run this netlist in LTspice? It will
>run in smartspice just fine. I guess it literally "runs" in
>LTspice, but seems to give the wrong answer when the cap is specified
>by w/l and uses a typical foundry model.
>
>A lot of this is preference. I did my own layouts for years and now
>hire others to do it.

Same here.

>I've found it more accurate to design resistors
>and capacitors myself rather than giving the layout person so much
>leeway by specifying values.

Likewise. Amazing how fast a digital layout guy can screw-up an
Analog layout.

> I also use the foundry specified models
>for these devices during simulation.

(I have models for well over 100 processes/foundries.)

I'm a circuit designer, thus I THINK in values, NOT physical
dimensions. Layout people like dimensions (naturally :).

I can netlist that way (using alternate templates), backing out the
dimensions by Algebraic computations {...functions...}, but this
doesn't help the layout guy (we like to minimize human intervention
:).

So, this weekend, my oldest son wrote an executable for me that reads
in a netlist, computes all the {...} and fills in numbers for L and W,
making for a clean, untouched by human hands, LVS netlist.

After refinement, we will put it up for sale on his website.

>
>I'd be interested in how a professional organizes their workflow. How
>about teaching me a few things? As I recall you use the old Microsim
>schematic capture for layout and simulate in pspice. Is this the
>perfect solution (and we should all copy) or do you do this for some
>other reason? Do you do your own layout? What tools do you use?
>
>o No M= on Bipolars?

Spice STANDARD is A= , but the literal is assumed, not written...

Q1 C B E [SUB} ModelName 5 <<---

>
>**********
>Symbol Names: NPN, PNP, NPN2, PNP2
>
>Syntax: Qxxx Collector Base Emitter [Substrate Node] model [area]
> + [off] [IC=<Vbe, Vce>] [temp=<T>]
>
>**********
>
>I don't see it in the documentation. It may by now be an undocumented
>feature and I haven't tried this lately.
>
>Again, you're free to draw as many parallel devices and work-arounds
>as you like. I'm trying to avoid this.

Just showed you how above ;-)

>
>Thanks for any professional advice :-)
>
>Regards,
>Larry
>

Jim Thompson

unread,
Mar 21, 2005, 10:44:34 AM3/21/05
to

"[area]" is a number, it IS NOT SPECIFIED as M=, except in
non-standard-conforming shit-for-brains simulators.

If you think HSpice is a good simulator you must be awfully young, or
substantially isolated from the real world ;-)

ldg

unread,
Mar 21, 2005, 11:18:06 AM3/21/05
to
On Mon, 21 Mar 2005 15:07:56 +0000 (UTC), kens...@green.rahul.net
(Ken Smith) wrote:

>In article <9rbr3156lgmhjsde2...@4ax.com>,
>ldg <as...@hotmail.com> wrote:
>[...]
>>Ltspice really does run well under wine. I was impressed. I didn't
>>do benchmarks, so have no way of knowing at this point how the extra
>>overhead might affect a long simulation.
>
>I think you will find that the extra overhead of running it under Windows
>(at least Win98) makes it run only a little slower than it does using
>wine. Is this what you mean?
>

Actually, I was wondering how wine itself works as an emulator. I'm
supposing it adds another layer between the application and the
hardware and would incur some overhead. Is this not the case?

I sometimes find I have to run sims that take days. In these cases,
speed counts.

>
>[...]
>>arranged them differently? If true it makes one wonder if the word
>>duh means anything to these folks. Then again, why is it some vendors
>>seem to be able to write distro independent software for linux and
>>while others can't?
>
>Some companies have good programmers and others don't. In some cases, it
>isn't that the software will not work just fine on some other system, it
>just that the maker only tests it on one version and makes their install
>script test for that specific version.
>

So you have to solve the problem caused by the various distro vendors
by writing different install scripts? I believe there actually is an
attempt to solve this problem by normalizing the libraries so 3rd
party software can always find them. This seems like a better
solution, but so far the various vendors haven't complied. Redhat
probably thinks their user base is "captured" by the way they have
these libraries arranged. The other vendors apparently refuse to
follow Redhat.

>
>I use SuSE to run "dosemu" to run the DOS Orcad. I had troubles with DOS
>orcad running dos windows on Windows machines. So far there has been no
>problem under dosemu. Unlike windows, xdosemu allows the DOS window to be
>resized etc.

I'll have to look at this - thanks!

One of the issues with switching to linux is that 3rd party software
vendors seem to not want to port their code to it. Nero did recently
and has been taking flack because their code is proprietary. If the
linux community wants linux to grow, they should encourage such
things. It also means they should take steps to ensure easy
operability between distros I think.

So far I've tried Fedora, Xandros, and SuSE. SuSE seemed to set up
the hardware more easily, though Xandros was also very good. Using a
memory stick on Fedora meant creating a special mount directory and
going through that process. SuSE and Xandros seemed to just recognize
a memory stick automatically. Only Xandros automatically set up Samba
so that it would function on my lan with win2k machines.

Regards,
Larry

ldg

unread,
Mar 21, 2005, 12:03:38 PM3/21/05
to
On Mon, 21 Mar 2005 08:13:40 -0700, Jim Thompson
<thegr...@example.com> wrote:

>Sure it can. In most Spices, it's done with subcircuits...
>
>xR node1 node2 <stray nodes> ModelName Params: L=100u W=2u M=4


I used to do such things when I used pspice. It causes you to look
for ways around its limitations. Unless doing a subcircuit adds
accuracy to the simulation, it's difficult for me to understand how
doing this is better.

Once in a while I use a capacitor symbol, for instance, that calls a
subcircuit to add stray to ground. This stray is constantly present
in an IC and if you don't account for it, it can cause real problems.
It isn't needed all the time, so I just change the pointer to another
symbol in another directory and it netlists out normally.

<snip>


Done the same way as R's...

xC node1 node2 <stray nodes> ModelName Params: L=100u W=20u (Some
nutcases use an M here, I don't, it's confusing... for segmented R's I
may adopt "S")

***********

It's less confusing to place the same capacitor over and over again?
If you say so.

Lets say you were drawing a 6 bit switched capacitor mdac. This
means you have to draw 1,2,4,8,16,and 32 cap arrays (in subcircuits
perhaps?). Or you could do one of your workarounds and create the
m=<M> function yourself I suppose. Then you'd have to figure out how
to do an lvs netlist for layout. You also could simply make the caps
sequentially larger, but I know you wouldn't do that because of
matching issues and the chance of confusing the layout person.

In any case, if I have a choice of simply adding m=32 on a cap, I'll
do this instead. If the schematic capture supports iterated
instances, I've also created these arrays by adding the appropriate
instance name on the device. C[0:31]

Regards,
Larry

"nutcase"

ldg

unread,
Mar 21, 2005, 12:21:57 PM3/21/05
to
On Mon, 21 Mar 2005 08:44:34 -0700, Jim Thompson
<thegr...@example.com> wrote:

>"[area]" is a number, it IS NOT SPECIFIED as M=, except in
>non-standard-conforming shit-for-brains simulators.

Really? How interesting. It's not an accepted spice "lexicon"?

Since Helmut says this has been implemented in LTspice now, this
simulator also is bad?

So using a 6 bit dac example again, you wouldn't weight the
transistors 1,2,4,8,16,32? Or you would just place 64 transistors?

Perhaps you'd write a subcircuit to create the M= function yourself?
Or maybe you'd try to make the transistors physically larger so the
current densities would match?

The dacs I've done seemed to be help greatly by doing these arrays.
It also seemed to me that if you want things to match they should be
the same, hence the arrays. Using M= greatly simplifies this.

Regards,
Larry

Jim Thompson

unread,
Mar 21, 2005, 12:21:11 PM3/21/05
to
On Mon, 21 Mar 2005 09:03:38 -0800, ldg <as...@hotmail.com> wrote:

>On Mon, 21 Mar 2005 08:13:40 -0700, Jim Thompson
><thegr...@example.com> wrote:
>
>>Sure it can. In most Spices, it's done with subcircuits...
>>
>>xR node1 node2 <stray nodes> ModelName Params: L=100u W=2u M=4
>
>
>I used to do such things when I used pspice. It causes you to look
>for ways around its limitations. Unless doing a subcircuit adds
>accuracy to the simulation, it's difficult for me to understand how
>doing this is better.

A "resistor" is a NATIVE Spice device. If it has more than two
terminals, or has parameters, it's a "subcircuit".

>
>Once in a while I use a capacitor symbol, for instance, that calls a
>subcircuit to add stray to ground. This stray is constantly present
>in an IC and if you don't account for it, it can cause real problems.
>It isn't needed all the time, so I just change the pointer to another
>symbol in another directory and it netlists out normally.

Since I have 100's of clients and 100's of models, I create my own
symbol set with Templates appropriate to the process.

For instance I don't just place an NMOS device, I place an XFAB-NMOS,
so that its strays are properly computed per the process.

>
><snip>
>Done the same way as R's...
>
>xC node1 node2 <stray nodes> ModelName Params: L=100u W=20u (Some
>nutcases use an M here, I don't, it's confusing... for segmented R's I
>may adopt "S")
>
>***********
>
>It's less confusing to place the same capacitor over and over again?

Sorry, I went back and placed the modifier after the wrong device. I
use M= on capacitors all the time. I have so many different types of
capacitors (in silicon) that I probably have 20 different symbol
types.

I just find M= for resistors confusing... parallel?? or serial??

>If you say so.
>
>Lets say you were drawing a 6 bit switched capacitor mdac. This
>means you have to draw 1,2,4,8,16,and 32 cap arrays (in subcircuits
>perhaps?). Or you could do one of your workarounds and create the
>m=<M> function yourself I suppose. Then you'd have to figure out how
>to do an lvs netlist for layout.

Naaaah! You missed the BEAUTY of my schematic capture. The
simulation TEMPLATE and the LVS TEMPLATE are different.

For instance, MOS devices, in the LVS netlist have no AD, AS, PD, PS,
etc., but do in the simulation netlist.

>You also could simply make the caps
>sequentially larger, but I know you wouldn't do that because of
>matching issues and the chance of confusing the layout person.
>
>In any case, if I have a choice of simply adding m=32 on a cap, I'll
>do this instead. If the schematic capture supports iterated
>instances, I've also created these arrays by adding the appropriate
>instance name on the device. C[0:31]

I can do that too, but generally limit such notation to buses.

>
>Regards,
>Larry
>
>"nutcase"

I presume you mean, by "nutcase", that you've never really used a good
simulator ;-)

Jim Thompson

unread,
Mar 21, 2005, 12:35:33 PM3/21/05
to
On Mon, 21 Mar 2005 09:21:57 -0800, ldg <as...@hotmail.com> wrote:

>On Mon, 21 Mar 2005 08:44:34 -0700, Jim Thompson
><thegr...@example.com> wrote:
>
>>"[area]" is a number, it IS NOT SPECIFIED as M=, except in
>>non-standard-conforming shit-for-brains simulators.
>
>Really? How interesting. It's not an accepted spice "lexicon"?

Nope. Get out a 2G6 or 3F5 manual.



>
>Since Helmut says this has been implemented in LTspice now, this
>simulator also is bad?

No. Knowing Mikey, I would bet the farm that he's implemented ANY
variation of the scheme, to allow netlists from any source.

>
>So using a 6 bit dac example again, you wouldn't weight the
>transistors 1,2,4,8,16,32? Or you would just place 64 transistors?

I'd just place the number after the ModelName per the standard. No M=
called for.

>
>Perhaps you'd write a subcircuit to create the M= function yourself?
>Or maybe you'd try to make the transistors physically larger so the
>current densities would match?
>
>The dacs I've done seemed to be help greatly by doing these arrays.
>It also seemed to me that if you want things to match they should be
>the same, hence the arrays. Using M= greatly simplifies this.
>
>Regards,
>Larry

ldg

unread,
Mar 21, 2005, 12:50:00 PM3/21/05
to
On Mon, 21 Mar 2005 10:35:33 -0700, Jim Thompson
<thegr...@example.com> wrote:

>I'd just place the number after the ModelName per the standard. No M=
>called for.

So you have different models for different sized devices?

Jim Thompson

unread,
Mar 21, 2005, 1:12:03 PM3/21/05
to

What part of "place the NUMBER after the ModelName per the standard"
do you have a problem with?

Q1 C B E [SUB} ModelName 5 <<<<----

Do you get it yet ?:-)

"Different sized" is a different game than "area".

"area" just creates multiple instances (paralleled devices).

"Different sized" implies different emitter size, or layout strategy.
These have different models, for instance....

.MODEL ab05a npn
[snip]
.MODEL ab05ai npn
[snip]
.MODEL ab16ai npn
[snip]
.MODEL ab1a npn
[snip]
.MODEL ab1ai npn
[snip]
.MODEL ab2a npn
[snip]
.MODEL ab2ai npn
[snip]
.MODEL ab4ai npn

etc....

Keith will probably recognize these names of a MAJOR semiconductor
house ;-)

ldg

unread,
Mar 21, 2005, 4:57:26 PM3/21/05
to
On Mon, 21 Mar 2005 15:07:56 +0000 (UTC), kens...@green.rahul.net
(Ken Smith) wrote:

>Some companies have good programmers and others don't. In some cases, it
>isn't that the software will not work just fine on some other system, it
>just that the maker only tests it on one version and makes their install
>script test for that specific version

Btw, this is the linux file system standard I believe they're trying
to implement:

http://www.pathname.com/fhs/


Regards,
Larry

Chuck Harris

unread,
Mar 21, 2005, 3:12:38 PM3/21/05
to
ldg wrote:
> On Mon, 21 Mar 2005 15:07:56 +0000 (UTC), kens...@green.rahul.net
> (Ken Smith) wrote:
>
>
>>In article <9rbr3156lgmhjsde2...@4ax.com>,
>>ldg <as...@hotmail.com> wrote:
>>[...]
>>
>>>Ltspice really does run well under wine. I was impressed. I didn't
>>>do benchmarks, so have no way of knowing at this point how the extra
>>>overhead might affect a long simulation.
>>
>>I think you will find that the extra overhead of running it under Windows
>>(at least Win98) makes it run only a little slower than it does using
>>wine. Is this what you mean?
>>
>
>
> Actually, I was wondering how wine itself works as an emulator.

The acronym for Wine is: <W>ine <I>s <N>ot an <E>mulator

Wine is an applications interface for windows code that runs under
x86 based linux systems. Just like 'doze 98 is an applications
interface for windows code that runs under DOS.

I'm
> supposing it adds another layer between the application and the
> hardware and would incur some overhead. Is this not the case?

No more so than the layer between windoes and dos. The underlying
operating system, linux, is a whole bunch more efficient than the
windows/dos mess.

-Chuck

ldg

unread,
Mar 21, 2005, 4:39:28 PM3/21/05
to
On Mon, 21 Mar 2005 11:12:03 -0700, Jim Thompson
<thegr...@example.com> wrote:

>>On Mon, 21 Mar 2005 10:35:33 -0700, Jim Thompson
>><thegr...@example.com> wrote:
>>
>>>I'd just place the number after the ModelName per the standard. No M=
>>>called for.
>>
>>So you have different models for different sized devices?
>
>What part of "place the NUMBER after the ModelName per the standard"
>do you have a problem with?
>
>Q1 C B E [SUB} ModelName 5 <<<<----
>
>Do you get it yet ?:-)
>
>

I misread your post. Sorry. I see that you're using <area> as a
multiplier.

This spice "lexicon" really isn't such a good standard, is it? To me
it would be better to have one syntax for a multiplier that can be
used across the devices. Hspice and smartspice seem to have settled
on m= for this. In fact, multiples are calculated by multiplying
area*m with 1 being the default for both.

If I could summarize, so far your professional approach seems to be
using subcircuits to get around Pspice simulator issues which you
justify the need for by pointing out that the original spice didn't
have more functionality anyway? Or did I miss something?

Many (maybe all?) of these work-arounds simply aren't needed anymore
and are things I used for years, then rejected when a simpler approach
became available. Some call this progress. Others call it an
improper spice lexicon or some such thing.

You also seem to take great pride in creating all of these pspice
compatible model files from the original foundry files. I prefer not
to edit the foundry given model files at all and treat these files as
"gold". It also makes it much simpler to incorporate updates.

LTspice parses the foundry models files without all the modifications,
so it would be preferable to your approach I'd think.

Regards,
Larry

ldg

unread,
Mar 21, 2005, 4:56:12 PM3/21/05
to
On Mon, 21 Mar 2005 15:12:38 -0500, Chuck Harris
<cf-NO-SP...@erols.com> wrote:

>> Actually, I was wondering how wine itself works as an emulator.
>
>The acronym for Wine is: <W>ine <I>s <N>ot an <E>mulator
>

Ha! Good to know ... :-)

There must be a lot of booze and good natured humor coming up with
some of these names.

>Wine is an applications interface for windows code that runs under
>x86 based linux systems. Just like 'doze 98 is an applications
>interface for windows code that runs under DOS.
>
> I'm
>> supposing it adds another layer between the application and the
>> hardware and would incur some overhead. Is this not the case?
>
>No more so than the layer between windoes and dos. The underlying
>operating system, linux, is a whole bunch more efficient than the
>windows/dos mess.

I'm hoping to transition to linux on all my machines, but first I
guess I have to jump through the Redhat hoop.

Thanks for the info!

Regards,
Larry

ldg

unread,
Mar 21, 2005, 4:43:08 PM3/21/05
to
On Mon, 21 Mar 2005 08:57:04 +0100, "Helmut Sennewald"
<HelmutS...@t-online.de> wrote:

>Hello Larry,
>the multiplier for Q is now in the LTspice documentation and it's
>implemeted.
>I wonder why it is exactly the same text as you posted.
>
>
>---- From the manual -------
>
>Q. Bipolar transistor
>
>Symbol Names: NPN, PNP, NPN2, PNP2
>
>Syntax: Qxxx Collector Base Emitter [Substrate Node] model [area]
> + [off] [IC=<Vbe, Vce>] [temp=<T>]
>
>---- End ----

Hi Helmut,

Is [area] the multiplier you were referring to? Sorry if I
misunderstood your post.

I've gotten used to using m= in Smartspice for all devices. I guess I
like the uniformity.

Regards,
Larry

Jim Thompson

unread,
Mar 21, 2005, 5:27:08 PM3/21/05
to
On Mon, 21 Mar 2005 14:24:35 -0800, ldg <as...@hotmail.com> wrote:

>On Sun, 20 Mar 2005 23:36:12 -0800, ldg <as...@hotmail.com> wrote:
>
>>>dg, You harp about things that you know not about. LTSpice can run
>>>ANY netlist... you're just too much the amateur to understand how.
>
>

>For completeness, I suppose I should include an example of the
>resistor error messages when the resistor is specified with w/l and a
>model.
>
>LTspice is apparently looking for the original spice syntax for the
>various parameters in the model and doesn't utilize much of the
>foundry supplied resistor model.
>
>The fact that it works for "semiconductor resistors" is not
>documented:
>
>
>Syntax: Rxxx n1 n2 <value> [tc=tc1, tc2, ...]
>
>The resistor supplies a simple linear resistance between nodes n1 and
>n2. A temperature dependence can be defined for each resistor
>instance with the parameter tc. The resistance, R, at will be
>
>R = R0 * (1. + dt * tc1 + dt**2 * tc2 + dt**3 * tc3 + ...)
>
>where R0 is the resistance at the nominal temperature and dt is the
>difference between the resistor's temperature and the nominal
>temperature.
>
>
>Running this file shows the error messages the simulator kicks out.
>It does find the sheet resistance and that provides an accurate
>nominal simulation in the rc below:
>
>
>
>LTSPICE test
>
>V1 1 0 pulse(0 5 10u 1n 1n 1)
>R1 1 2 1e4
>C1 2 0 1e-9
>XR2 1 3 rny10k
>C3 3 0 1e-9
>
>.SUBCKT RNY10K a b
>RR10 N_1 b NY W=4.4U L=88U
>RR9 N_2 N_1 NY W=4.4U L=88U
>RR8 N_3 N_2 NY W=4.4U L=88U
>RR7 N_4 N_3 NY W=4.4U L=88U
>RR6 N_5 N_4 NY W=4.4U L=88U
>RR5 N_6 N_5 NY W=4.4U L=88U
>RR4 N_7 N_6 NY W=4.4U L=88U
>RR3 N_8 N_7 NY W=4.4U L=88U
>RR2 N_9 N_8 NY W=4.4U L=88U
>RR1 a N_9 NY W=4.4U L=88U
>.ENDS RNY10K
>.tran 1u 0.1m
>
>.model ny r rsh = 50
>+ dw = 0.08e-6 dlr = -0.8e-6
>+ cox = 1.3e-4 capsw = 0.060e-9
>+ tc1r = 4.0e-4 tc2r = 1.1e-6
>+ tref = 25
>*
>
>.end
>
>Again, this works fine in Smartspice. No subcircuits needed :-)
>
>Regards,
>Larry

Take it up with Mikey. You've wasted several hours of my time. No
more. Fookin' amateur ;-)

ldg

unread,
Mar 21, 2005, 5:24:35 PM3/21/05
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On Sun, 20 Mar 2005 23:36:12 -0800, ldg <as...@hotmail.com> wrote:

>>dg, You harp about things that you know not about. LTSpice can run
>>ANY netlist... you're just too much the amateur to understand how.

Jim Thompson

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Mar 21, 2005, 5:08:39 PM3/21/05
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On Mon, 21 Mar 2005 13:39:28 -0800, ldg <as...@hotmail.com> wrote:

>On Mon, 21 Mar 2005 11:12:03 -0700, Jim Thompson
><thegr...@example.com> wrote:
>
>>>On Mon, 21 Mar 2005 10:35:33 -0700, Jim Thompson
>>><thegr...@example.com> wrote:
>>>
>>>>I'd just place the number after the ModelName per the standard. No M=
>>>>called for.
>>>
>>>So you have different models for different sized devices?
>>
>>What part of "place the NUMBER after the ModelName per the standard"
>>do you have a problem with?
>>
>>Q1 C B E [SUB} ModelName 5 <<<<----
>>
>>Do you get it yet ?:-)
>>
>>
>
>I misread your post. Sorry. I see that you're using <area> as a
>multiplier.

That is the Spice "Standard"



>
>This spice "lexicon" really isn't such a good standard, is it? To me
>it would be better to have one syntax for a multiplier that can be
>used across the devices. Hspice and smartspice seem to have settled
>on m= for this. In fact, multiples are calculated by multiplying
>area*m with 1 being the default for both.

To those of us who stopped netlisting by-hand maybe 20 years ago, this
is no longer an issue... the symbol TEMPLATE does all the work.



>
>If I could summarize, so far your professional approach seems to be
>using subcircuits to get around Pspice simulator issues which you
>justify the need for by pointing out that the original spice didn't
>have more functionality anyway? Or did I miss something?

You've missed a lot. There are a limited number of NATIVE DEVICES is
Spice, all else are subcircuits.

>
>Many (maybe all?) of these work-arounds simply aren't needed anymore
>and are things I used for years, then rejected when a simpler approach
>became available. Some call this progress. Others call it an
>improper spice lexicon or some such thing.

I call it "head-up-the ass syndrome". You are really so clueless I
might suppose your father is Fred Bloggs ;-)

>
>You also seem to take great pride in creating all of these pspice
>compatible model files from the original foundry files. I prefer not
>to edit the foundry given model files at all and treat these files as
>"gold". It also makes it much simpler to incorporate updates.

Excuse me? What makes you think I edit the original foundry files?



>
>LTspice parses the foundry models files without all the modifications,
>so it would be preferable to your approach I'd think.
>
>Regards,
>Larry


I really am tiring of trying to help what appears to be a student,
only to have them turn on me, implying I know nothing.

If you're on this side of the pond you are so ignorant you must be a
Democrat.

Other side of pond, you must be a relative of Bemelman.

You're definitely a fookin' amateur ;-)

ldg

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Mar 21, 2005, 5:52:16 PM3/21/05
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On Mon, 21 Mar 2005 15:08:39 -0700, Jim Thompson
<thegr...@example.com> wrote:


>I really am tiring of trying to help what appears to be a student,
>only to have them turn on me, implying I know nothing.

>You're definitely a fookin' amateur ;-)


Of course I didn't ask others recently how to search my hard drive :-)

Regards,
Larry

ldg

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Mar 21, 2005, 6:18:03 PM3/21/05
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On Mon, 21 Mar 2005 15:27:08 -0700, Jim Thompson
<thegr...@example.com> wrote:

>Take it up with Mikey. You've wasted several hours of my time. No
>more. Fookin' amateur ;-)
>
> ...Jim Thompson
>--

To JIM:

Take your lithium. Rent Napoleon Dynamite. Grab a good cabernet and
enjoy life :-)

You may want to reconsider saying things like this to others - "You
harp about things that you know not about". I was curious at that
point what you might actually know. Not curious now. :-)

TO THE GROUP:

Hopefully the exchange might provide some insight to others on the
various topics and wasn't too distracting. If so, let me apologize.

Sorry for taking over the thread.

I had fun though. :-)

Regards,
Larry

Jim Thompson

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Mar 21, 2005, 6:25:13 PM3/21/05
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Bwahahahahaha!

Fookin' amateur!

Though I'm a Scot, not Irish, I like that phrase "Fookin' amateur";
have to add it to my repertoire ;-)

Ken Smith

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Mar 25, 2005, 5:00:04 PM3/25/05
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In article <1jrt31dugusf979sl...@4ax.com>,
ldg <as...@hotmail.com> wrote:
[....]

>Actually, I was wondering how wine itself works as an emulator.

Wine works very well indeed as an emulator even though it is in fact not
an emulator but a port of the windows API onto linux.

> I'm
>supposing it adds another layer between the application and the
>hardware and would incur some overhead. Is this not the case?

Consider the case of a request to write to a file:

The typical Windows application does this:

(1) The object that is requesting to be written calls its virtual method
that is used for writing.

(2) The write virtual method calls the virtual method for each of its
component parts.

(3) Each component part calls the virtual method that is part of the file
handling stuff in MFC.

(4) The file handling stuff creates the needed structure to pass to the
windows API.

(5) The windows API recieves the request and burries it in warm peat for
aging.

(6) The windows API hands the request to the 32 bit DOS function.

(7) The 32 bit DOS function calls the section of the device driver that
does writing

(8) The device driver waits for the tubes in the disk drive to warm up and
then dribbles the data into the srive.

Under wine, items 5 to 8 change to this:

(5) The wine code recieves the request.

(6) wine passes the request to the kernal function

(7) The kernal transfers the data to a buffer and flags it as needing to
be written.

(8) When time permits or there are not enough buffers left, the Kernal
calls the code for writing on this type of disk.

(9) The write actually happens.

>>Some companies have good programmers and others don't. In some cases, it
>>isn't that the software will not work just fine on some other system, it
>>just that the maker only tests it on one version and makes their install
>>script test for that specific version.
>>
>
>So you have to solve the problem caused by the various distro vendors
>by writing different install scripts?

In many cases, it is just a matter of using the software from the good
programmers and ignoring the software from the bad ones.

> I believe there actually is an
>attempt to solve this problem by normalizing the libraries so 3rd
>party software can always find them.

It is less about normalizing and more about picking a minimum standard and
going with that.

<RANT>
Bad programmers assume that the target machine has all the latest stuff.
Good programmers only enforce the requirements that actually matter in
their code. Bad programmers hard code the locations and versions of
everything. Good programmers allow for things to be specified at install
time.
<\RANT>

> This seems like a better
>solution, but so far the various vendors haven't complied. Redhat
>probably thinks their user base is "captured" by the way they have
>these libraries arranged. The other vendors apparently refuse to
>follow Redhat.

Dead Rat has lots of silly ideas. But then so do lots of other folks.
Altera just brought out a version of Quartus that runs under Linux, if you
have the right version of Read Hat and if you have the right version of QT
and if you have the right version of Glibc and if you place your left hand
on top of your head while you install it. All Quartus really is, is a
compiler and a text editor. They could have left the editor out. There
is no reason a compiler needs any such specifics about the machine it will
run on.

[...]

>One of the issues with switching to linux is that 3rd party software
>vendors seem to not want to port their code to it. Nero did recently
>and has been taking flack because their code is proprietary. If the
>linux community wants linux to grow, they should encourage such
>things. It also means they should take steps to ensure easy
>operability between distros I think.

Nero comes free with many DVD burners etc. The free version is not the
Linux version. I think this is why they are getting flack. If they gave
you the Linux version when you bought the DVD burner, most users would not
care that they did not get the source code.

[...]


>So far I've tried Fedora, Xandros, and SuSE. SuSE seemed to set up
>the hardware more easily, though Xandros was also very good. Using a
>memory stick on Fedora meant creating a special mount directory and
>going through that process. SuSE and Xandros seemed to just recognize
>a memory stick automatically. Only Xandros automatically set up Samba
>so that it would function on my lan with win2k machines.


My work machine runs SuSE 9.2. It almost got samba right on the first
try. At home I run SuSE 8.2. The samba set up in it was completely
broken. There are signs of progress.

ldg

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Mar 26, 2005, 12:22:00 AM3/26/05
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Thanks for the thoughtful reply!

Regards,
Larry

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