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Update: Varistor/MOV Spice Modeling

Varistor/MOV Spice Modeling has been updated.

See VaristorMOV.zip on the Device Models & Subcircuits Page of my website. ...Jim Thompson

-- | James E.Thompson | mens | | Analog Innovations | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | San Tan Valley, AZ 85142 Skype: skypeanalog | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at

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| 1962 | I love to cook with wine. Sometimes I even put it in the food.

Reply to
Jim Thompson
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Encrypted! Not very general.

Given how imprecise MOVs are, seems like a couple of zeners and resistors, and maybe a capacitor, would be plenty good enough.

MOVs "wear out", too. Did you include that?

--

John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com
Reply to
John Larkin

To conceal my techniques. Did you read... 8 lines versus 34 ??

Parameterizable to any MOV... read!

Good enough for you, perhaps >:-}

Typical Larkin sand-in-air... you can't help but be an asshole. ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| San Tan Valley, AZ 85142     Skype: skypeanalog  |             | 
| 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

Good enough for anybody. MOVs are not precise parts.

Did I hurt your feelings by not admiring your encrypted MOV model?

I really can't imagine why anyone needs to Spice a MOV. The things that matter (power dissipation, joule capacity, wearout) aren't in the model.

--

John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com
Reply to
John Larkin

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

8 lines? Looks more like 20 to me.

Tim

--
Seven Transistor Labs, LLC 
Electrical Engineering Consultation and Contract Design 
Website: http://seventransistorlabs.com
Reply to
Tim Williams

That's LTspice's encryption scheme that adds all those extra characters. ...Jim Thompson

-- | James E.Thompson | mens | | Analog Innovations | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | San Tan Valley, AZ 85142 Skype: skypeanalog | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at

formatting link
| 1962 | I love to cook with wine. Sometimes I even put it in the food.

Reply to
Jim Thompson

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

Well either way, your claim is absurd, because the file size (not that 2k files are any concern these days) certainly isn't 8 lines, and without cracked encryption (anyone know if LTSpice / PSpice / HSpice encryption has been cracked? anyone working on it?), impossible to verify.

There's also the possibility that fewer lines contain more math, resulting in worse execution time or convergence anyway.

But really, I'm guessing it's your tanh fit stuff, which you've posted about publicly before. You also claim it's based on publically published curves. So hiding it is all the more absurd...

Tim

--
Seven Transistor Labs, LLC 
Electrical Engineering Consultation and Contract Design 
Website: http://seventransistorlabs.com
Reply to
Tim Williams

New technique. It definitely works. Try it or not, I don't care. It was originally posted to the LTspice List where the question was broached initially.

Those with interest in circuit work should subscribe to the LTspice List... you'll learn some new techniques... and not be annoyed by cockroach invasions into technical threads. ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| San Tan Valley, AZ 85142     Skype: skypeanalog  |             | 
| 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

Seems pretty pointless at your age, Jim. Are you ever going to pass on all those pearls of wisdom, or are you going to take them to the grave like King Tut?

Soon would be good, if you're ever going to.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 

hobbs at electrooptical dot net 
http://electrooptical.net
Reply to
Phil Hobbs

Right now I'm making money at it. Why should I give away the store? Does Larkin post a _complete_ schematic of his instruments and manufacturing techniques here? ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| San Tan Valley, AZ 85142     Skype: skypeanalog  |             | 
| 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

Because you're in your mid 70s. I know your dad lived into his early

90s, and was pretty sharp till the end, but there's no guarantee that you'll do the same. What do you want your legacy to be? It's pretty late not to be thinking about that, especially given the amount of time and energy it will take to pass on the best of what you know in a form accessible to young people.

John L.'s company will probably be manufacturing stuff long after he's retired, and he isn't the sole designer, so that isn't the same case at all.

Also you vastly overestimate the opportunity cost of publishing stuff--it's usually a net win.

My book gives away the majority of what I know about what I do, and besides helping a lot of young folks (which was the point of the exercise), it has been the foundation of my consulting practice. The first edition was published when I was 40.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 

hobbs at electrooptical dot net 
http://electrooptical.net
Reply to
Phil Hobbs

An MOV model is "the store"? That's sort of sad.

Sometimes I post actual product schematics, usually sheets relevant to the topic, and photos of real boxes and boards. Sometimes I post (non-encrypted!) Spice files. Sometimes I post ideas and scribbles that I just imagined.

I don't post manufacturing techniques, because my production people do that, and it's fairly standard stuff. I have posted a lot of breadboarding techniques, stuff that I do myself.

I don't post encrypted Spice circuits and then tell people that I'm smart, just because I say so.

I still don't know why your thing would be any better than a couple of zeners and resistors, and you won't say why.

--

John Larkin         Highland Technology, Inc 
picosecond timing   laser drivers and controllers 

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com
Reply to
John Larkin

OK. I'll divulge all my "secrets":

(1) All derivatives must exist and be continuous (2) All functions must be BOUNDED smoothly, per (1) above.

That's all there is to it other than knowing circuit design at the device level which you can pick up easily with 50 or so years or experience >:-}

Seriously.

More seriously, leukemia testing begins tomorrow.

I'll consider your advice... maybe it is time to do a load dump. ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| San Tan Valley, AZ 85142     Skype: skypeanalog  |             | 
| 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

I'm praying for good test results for you.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 

hobbs at electrooptical dot net 
http://electrooptical.net
Reply to
Phil Hobbs

GFYU ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| San Tan Valley, AZ 85142     Skype: skypeanalog  |             | 
| 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

After you get well, you're welcome to try.

--

John Larkin         Highland Technology, Inc 
picosecond timing   laser drivers and controllers 

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com
Reply to
John Larkin

On a related note then, if anyone has something they'd like to model, I could take a crack at it.

I suspect Jim isn't doing anything I don't know, and if he sees some examples, maybe he'd even admit what it is, too ;-)

Tim

--
Seven Transistor Labs, LLC 
Electrical Engineering Consultation and Contract Design 
Website: http://seventransistorlabs.com
Reply to
Tim Williams

Perhaps not the right place in the thread to say this, but what problems would come up if you modelled a varistor as a behavioural current source with I = k* V^alpha in series with a bulk resistance? I've had pretty good luck with that model (just not in SPICE).

Reply to
Ralph Barone

Bwahahahahahaha! I needed a laugh right now.

How about an NCP1072? That was requested on the LTspice List >:-} ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| San Tan Valley, AZ 85142     Skype: skypeanalog  |             | 
| 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

How about a resistor, diode, voltage source?

A couple in parallel if you want some curvature.

Bridge rectifier if you need bipolar.

--

John Larkin         Highland Technology, Inc 
picosecond timing   laser drivers and controllers 

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com
Reply to
John Larkin

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