LTSpice Model for LM3914

[eTech]

Hi

I've developed a new LM3914 simulation model for use with LTSpice.
It appears to work but I would like someone else to test and provide some feedback.
I've included dot bar logic in the model to handle cascading of multiple LM3914's

Anyone interested?

thanks..

 

[ericgibbs]

hi eT,
Please post your model etc, I will give it a run.
E

 

[alec_t]

I'd be interested to compare it with the model I developed last year.

 

[eTech]

Hi Eric and Alec,

I'm attaching some same images of some test circuits I made.

I'll be uploading an encrypted .sub file along with a .asy symbol file.
But before I do...are you guys OK with that?

eT

 

[alec_t]

Ok with me.
Have you modelled the slight overlap/fade from LED to LED in dot mode? It's difificult to tell from the waveforms.

 

[eTech]

Ok with me.
Have you modelled the slight overlap/fade from LED to LED in dot mode? It's difificult to tell from the waveforms.

Cool...
I have it on my list of improvements and still need to figure out how to do that but I definitely saw that on the bench. For now, I've only delayed the rising edge.

 

[eTech]

Ok guys...here you go.

On my PC, the schematic with three cascaded devices takes 2.2 seconds to converge.
Please give it a road test and provide some feedback.

Thanks

eT

 

[ericgibbs]

hi eT,
Downloaded your zip, sorry I do not wish to deal with encrypted files.

Why do you consider it necessary to encrypt open source LTSpice models.?

Eric.

 

[alec_t]

Since your model is encrypted I can't compare it with mine . As Eric says, why encrypt it?

 

[eTech]

Alec, Eric,

(sigh)....ok....then never mind guys...but I did ask in post #4 if you were ok if the file was encrypted.

Thanks anyway...

eT

 

[ericgibbs]

hi eT,
Can you say why it needs to be encrypted.?
E

 

[eTech]

hi eT,
Can you say why it needs to be encrypted.?
E

Hi Eric

Simply to protect what has taken me a considerable amount of time and effort to develop.
Even if it may only be for a short time.

The model will only work with LTSpice anyway...

eT

 

[ericgibbs]

hi eT,
Alec and I have already created and posted LM3914 and LM3915 LTSpice models as open source, in what way is yours unique.?

Eric

 

[alec_t]

has taken me a considerable amount of time and effort to develop

Me too, but I hope others can benefit from my effort and suggest improvements

 

[eTech]

hi eT,
Alec and I have already created and posted LM3914 and LM3915 LTSpice models as open source, in what way is yours unique.?

Eric

The model you've posted uses arbitrary nonlinear controlled sources (b devices) for circuit representation.
Which is not a bad thing....just different. The model I posted is a Macro-model design that uses a combination of functional elements and LTSpice proprietary devices. It's very fast but can only run with LTSpice.

I'm getting the impression I may have stepped on someone's toes here....which was not my intent.
I did ask if you were ok with my post. If I stepped on someone's toes, I apologize...

eT

 

[ericgibbs]

I'm getting the impression I may have stepped on someone's toes here....which was not my intent.
I did ask if you were ok with my post. If I stepped on someone's toes, I apologize...

hi eT,
Not at all, it was just curiosity wanting to know why it was encrypted.
Regards
Eric

 

[eTech]

hi eT,
Not at all, it was just curiosity wanting to know why it was encrypted.
Regards
Eric

Ok...we'll..thanks anyway guys...

eT