If I want to set Gmin, Abstol, or other LT Spice parameters, and have them travel with a circuit model, how can I do this? Is there some text thing I can include on a particular schematic that will set these params for Spice? The LT Spice Simulation/Control Panel/Spice window indicates that these settings are not inherently carried across program invocations. Gmin of 1e-12 is just too leaky!
John
Isn't it like this?
.option abstol=
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
In PSpice, options _stay_ with the schematic.
I'm only a casual user of LTspice, but it appears that you can get the same effect in LTspice by clicking on "Spice Directive" (furthest right in the tool bar) and type in the .options line information that you want.
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Stormy on the East Coast today... due to Bush\'s failed policies.
Cool. Seems to work.
Thanks.
John
Except you need .options gmin=1e-15, or whatever.
("abstol" is current resolution.)
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Stormy on the East Coast today... due to Bush\'s failed policies.
Use .PARAM or better yet .OPTIONS ??
I pointed out the "Spice Directive", .op symbol, right-most in the toolbar is where you enter such items, but John keeps ignoring me, 'cause he's an asshole who can't take criticism... much like Slowman ;-)
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
The first sign of senility is persistently trying to be an asshole
The second sign of senility is touting your company\'s wonderful
circuit designs as your own, while posting amateur crap on S.E.D
The third sign is acting like Polly Prissypants :-)
Turns out you click the funny little letter icon, upper-right, and then type
.OPTION Gmin=1e-18
Plop the resulting string somewhere on your schematic. That makes the diodes work much better.
This shows up in the ascii netlist file as stuff like...
TEXT -600 -8 Left 0 !.option Gmin=1e-18 TEXT -608 32 Left 0 !.option abstol=1e-18 TEXT -608 72 Left 0 !.option chgtol=1e-18
John
It's been a while but IIRC you can also use ".option" just once, followed by all the parameters you'd like to change, separated by spaces.
Careful with the computer. When doing stuff like this on a Pentium in the 90's ... tsssk ... tick, tick, tick ... *PHUT* ... Pentium gone.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
.OPTION CPU=AMD
:-)
As consultants we often have to take what's there at the clients offices.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
That can sting a little, at times:
.OPTION CPU=IMSAI
Jon
IEEE Spectrum just had an interesting article about legacy chips that made history, and the 8080 was at least mentioned (under 8088 which was the real break-through).
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
On Wed, 13 May 2009 10:26:15 -0700, Joerg wrote:
Yes. At the time, I was just going to college and was paying my own way (no money within our family and I was the oldest.) I had read the article on the Mark 8 Personal Minicomputer in Radio Electronics in
1974, but didn't feel ready/competent/money-flush to go for it at the time. Then I saw the articles and ads that followed a little later in Popular Electronics for the MITS ALTAIR 8800 and I went for it. Bought the system (with just 256 bytes of memory) without a power supply or any memory to fit the other three 256x8 static ram sockets on the main board because I couldn't afford to add either. A simple power supply was about my level of design skill as a hobbyist, so I did that part. I also was being paid part time to solder probes for Tektronix to help pay my way, so soldering I could also do. In no way was I prepared for what happened when I finally splurged and later on (when they became available) bought their 4k dynamic ram cards. They didn't function and I was nearly in tears because of my lack of skill to do more than solder them up. I spent the next 6-7 weeks learning and eventually was able to work out the patches to make with the help of someone's scope and the thoughts of the few friends in my age group that I had at the time. In the process, I paid dearly in emotion but also learned some digital and enough analog to actually do something about the problems. I wouldn't put anyone through that, intentionally. But in the end, I wound up having a story written about me in a suburban, local newspaper which I didn't deserve but I suppose happened more because at the time such things just didn't happen to "regular folks," so it was a nice personal-interest story for them. I don't know how they found out. But I just felt very embarrassed about the whole thing.I have very mixed feelings about that period. I suppose most of us do about when we were just getting past the idea of being 18 years old, though.
Jon
We all went through that, although not nearly as hard as you. I vividly remember having scratched together all my money and buying one (!) VMOS FET that could be used as a power amp up to 100MHz. I thought that it can't be much of a stretch from there to 145MHz, that datasheets were always way too conservative, that I'd already wrestled a reliable kilowatt out of five TV flyback tubes and therefore was quite invincible and yada, yada, yada. Built the amp, worked. Yeehaw! After about 10mins of radio conversations ... phut ... *POP*
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
I'm not sure if you were here in the US when you were that young, or not. At the time when I was growing up, welfare simply didn't exist (yes, it existed on paper but there was almost no expenditure at all and what little of it existed didn't apply to me.) I worked the fields as a child just to eat, literally. And had zero health care. Not possible. Lived in a home without walls, etc. You get the idea. Not a lot of extras.
I improved upon my public education by going to the libraries, so I consider them like gold today. They are the ONLY true safety net that exists for those willing to work for their own science education and where otherwise "the system" fails them here in the US. Schools may not be well funded or have other problems in attracting and holding excellent science teachers. Your own family may be a mess and unable to cope with or even understand how to try. Everything else can go crumbling around you, but the one thing left that is out there which you yourself can control (if they exist in your area, at all) is your access to a library system. With that, even a child can compensate a bit for all of the other failures. The library is a golden community resource that should always be well funded. Period. It saved my ass and allowed me to get to the point where I could achieve an 800 on the SAT math section and could qualify for scholarships. Believe me, I support the library system here now. Maybe people don't use it or need it quite the way I did, but I like just knowing that it is there
-- it represents something to me, a kind of last fall-back position for an educated society.. that last educational safety net that can catch a child when every other part fails. And using it doesn't require adult-level skill sets, mostly just what you can acquire through even the most mediocre public education system.
But when all this came about, I was paying for my own rent, food, working as much as I could handle while also going to school, etc. I had a very hard time coming up with the 2 times $295 it cost me to buy those two dynamic ram cards. That money wasn't just slush funds -- it literally put me at risk and took food off the table and health care out of reach, should I have needed it. It was serious. There was very little of a safety net for folks like me, then. I gambled. And came up short, for a time. And learned something in the process, too.
Jon
I remember you writing about that, could have been in the MSP430 group.
It was in Germany. My parents were (and are) great but kids back then didn't have the financial resources as today and I wasn't the only child in the family. 50-100 Deutschmarks for a lone electronic part like a transistor was outrageous, don't remember the exact amount but it drew my piggybank straight down to zero. Stuff was a whole lot more expensive over there.
I spent whole afternoons in the library and probably there wasn't one week in my youth when I didn't have at least one checked-out textbook at home. Four weeks max back then, one extension but only if nobody else had dibs on it (someone usually did). Our library wasn't good for techies, didn't have much. The better one was about five miles away and one challenge was to get the books there or back home without them becoming wet in the rain on the bicycle.
Lately I donated technical books that I could spare, still very much current. Once I had to look up a radar equation, so went to the local library with notepad in hand to look for "my" book. Not there. Seems they send them on to universities or bigger libraries which is quite sad. There was no other book on their shelves that even remotely teaches beamforming and Doppler. Most aisles have novels or thrillers :-(
Yikes! I didn't have that kind of money back then. Well, once I did. Worked my butt off at a meat processing plant, grueling work and definitely not for the faint of heart but paid about $4/hr which was a fortune. This was so I could buy a used and quite banged up ham radio transceiver after getting my license (a Heathkit HW-100). Pa had to drive my to the seller because it was too heavy to schlepp onto a train.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
And I had to trudge thru the snow to get to both high school _and_ MIT... uphill both ways ;-)
Worked part-time as a technician at MIT making, on average, $20/week.
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Stormy on the East Coast today... due to Bush\'s failed policies.
And the wind was somehow always blowing in your face ...
So did I, Aachen University in Germany, 10 Deutschmarks an hour which back then was probably around $3-4. You could live pretty high on the hog with that. Initially I built up a "Heathkit-style" homebrew program for students so they gain some real hands-on experience. After they found out that I didn't really "need" the masters to do engineering, part of my job became rescuing capsizing masters projects. One of the most fun experiences was when the academic director had to call in sick, none of the Ph.D. candidates was on site or had time and I was asked to hold the training lecture in the big auditorium. Here I was, in front of
200 students or so, hadn't even done the exam they were training for, and felt like da professor. Oh, and no microphones back then.-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
I was making $1.90/hour... but, then, I'm just shy of my 70th year. When I went to Motorola, straight from MIT, I made $6600.00 annual, $126.92/week ;-)
Amazing how well we lived on that amount of money!
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Stormy on the East Coast today... due to Bush\'s failed policies.
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