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Hooking up transistors in LTSpice

Ok, will have to figure out that format then. And also how to make sure LTSpice PWM chips transfer correctly. That'll be a problem at times because LTC often doesn't have all pins and features in the sim models. Throws me a curve every time I need to sync a switcher, and I have to do that a lot.

I think the political contrast between Berkeley and Pleiskirchen is huge :-)

Seriously, a guy from a Bavarian town down there told me that in his town it happened that a vote was cast for the SPD (like the dems here). Immediately comments were heard such as "This is unbelievable. Who was that? I want to know!"

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Regards, Joerg

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Joerg
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Study up on LTspice symbol notation and Eagle notation and roll your own.

ANY Spice variant netlists the "pin" order as the same as the underlying subcircuit instantiation (which must match the same order as in the library declaration, or all hell breaks loose). ...Jim Thompson

--
| James E.Thompson, CTO                            |    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     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

That in itself is going to become an issue which needs some fancy translating routines. As I mentioned, LTC's models often omit certain functions and pins. So if pin 3 is a sync pin and that ain't there in their model ... poof. A SW routine would need to notice that and reshuffle all subsequent pins. Which will not be trivial considering that LTC's models or not ASCII but proprietary.

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Joerg

He who lives by invisible pins dies by invisible pins :-)

Likewise, he who lives by encrypted models, dies likewise :-) ...Jim Thompson

--
| James E.Thompson, CTO                            |    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     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

Funny you should say that - I did the same search a month ago (failed). I'm quite up to the task of writing the code, but the documentation of the formats is so weak, especially LTSpice... I'd be delighted if someone creates a set of examples; *this* Eagle file should convert to

*that* LTSpice file... with enough examples to constitute a small test suite. It wouldn't be hard to source an Eagle programmer who'd implement that, and refine from there.

Clifford Heath.

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Clifford Heath

Thanks, Clifford. Then I can restrict my search about anything in the last 30 days :-)

At least for transistor-level stuff this would be nice. I've had two manual transcription errors from LTSpice into Eagle. Both caught in a timely manner but it's just a matter of time until one slips through.

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Yup, that is one of the not so nice behaviors of LTSpice, no real-world pin numbers.

Ever looked at PSpice models for PWM chips and such? You'll be unpleasantly surprised ;-)

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:-)

I have a policy of refusing to use parts with encrypted models. ...Jim Thompson

--
| James E.Thompson, CTO                            |    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     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

Is there a free demo version of Eagle? ...Jim Thompson

--
| James E.Thompson, CTO                            |    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     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

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John S

:-)

Good luck with that. Then you have become unable to design modern high frequency switch mode converters, lighting controllers, motor controllers, avionics and a whole lot of other stuff. Unless the client is willing to invest some six-digit sum into a chip. Which happens on occasion even in my world of mostly board-level design (like right now) but they'd read me the riot act later if it turns out there was a COTS chip for a buck fifty all along.

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Jim, give it a shot. It contains some quirks such as the fact that "cut" really means "copy". But other than that, if they really introduce a hierarchy with version 6 it'll be the best schematic editor there ever was, IMHO. Except for Orcad-SDT, that is, because that was clearly the best. Anyhow, then they'll receive an upgrade order and a check from me.

The library editor of Eagle is not very intuitive. While the schematic editor can be learned by just hopping into the saddle (watch your hip there ...) you'll need the manual for the lib editor or it'll frustrate you. I have the book but it is available as PDF for download.

For the record: Hard crashes of Orcad 16.3 in the first month: Several dozen. Crashes (any kind) of Eagle in all the years I had it: Zero.

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:-)

Amending my statement slightly...

If the vendor will assure me that the encrypted model is transistor level rather than behavioral, I'll use it. ...Jim Thompson

--
| James E.Thompson, CTO                            |    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     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

For the record, PSpice Schematic crashes in the past _multi-years_: ZIPPO! ...Jim Thompson

--
| James E.Thompson, CTO                            |    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     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

Eagle? Wheeeee!

(1) Extraordinarily crude schematic capture!

(2) You WILL need a script to convert its netlist output to LTspice compatible :-( ...Jim Thompson

--
| James E.Thompson, CTO                            |    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     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

Romans.

huge :-)

Then you aren't designing switch mode supplies much :-)

I recently had the "pleasure" to use a transistor-level model (encrypted) and some sims took forever. However, since AGW must have been called off the increase in office temp from the PC-turned-spaceheater was welcome. We still blew through five cords and still heating right now :-(

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Regards, Joerg

http://www.analogconsultants.com/

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Tried it already? Give it some more time.

What's crude about it? Moving stuff around is a lot smoother than with Orcad. And as for PSpice schematics, it's nice that it never crashes but with many clients you will have compatibility issues if schematics need to be exchanged.

T'is what I thought :-(

The same would probably be true for most other CAD expcet the Orcad-PSpice combo or other combos. But I don't like software that crashes a lot.

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Regards, Joerg

http://www.analogconsultants.com/

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Eagle doesn't appear oriented to simulation, just board work. I couldn't find any means to create netlisting "templates". That feature may exist somewhere in its obscurity. If you can find a way to set "templates" for parts, then you won't need a script. Otherwise you're "fooked" ;-)

With PSpice Schematics I can create an OrCAD Crapture equivalent with a single click, for those clients that want it.

Inbound, all I need is a PDF and a netlist... simply call the netlist into PSpice, no need to re-create a schematic. ...Jim Thompson

--
| James E.Thompson, CTO                            |    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     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

Romans.

huge :-)

Generally roll my own, though a recent need suggests I use MY custom chip to talk to a LT switcher part.

Often I find transistor level parts can actually "run" faster since they converge more easily.

This time of year, the A/C barely runs, so my office gets hot. A temporary squirrel-cage in the door-way cures that :-) ...Jim Thompson

--
| James E.Thompson, CTO                            |    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     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

Not sure what you mean by templates. You have the symbol, the footprint, pin designators, names and such. V5 which you probably downloaded also has several extra attribute fields. Netlisters are usually either taken from the shared area on the Cadsoft server or you can write your won using script or (preferably) the rather powerful user language in order to create a ULP. People have do that for all sorts of non-Cadsoft layout programs but not SPICE. Then nice thing about Eagle is that it is fairly open.

A fully compatible 16.3 file? Sorry, but that I can't believe. More importantly, you can't read in a version 16.3 file.

Ok, that is very different in my work. Looks like the PSpice schematics route wouldn't work for me then.

--
Regards, Joerg

http://www.analogconsultants.com/

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