I've updated the first page to include a section for any interesting ideas and tutorials that anyone may wish to submit.
Thank you, Mooly...
slight ommision: to be able to add custom component libraries, one sometimes is required to take ownership of the LTC directory, since Windows installations are likely to grant full-access only to the "Trusted installer" and blocking the user (administrator) from write/delete actions.
slight ommision: to be able to add custom component libraries, one sometimes is required to take ownership of the LTC directory, since Windows installations are likely to grant full-access only to the "Trusted installer" and blocking the user (administrator) from write/delete actions.
You're welcome 🙂
If you have a worked example showing what you want then we can include that in the thread. I've tended to steer clear of altering libraries, preferring to add any 'one offs' individually to the relevant project... which is also another way of saying I'd be starting from zero on that one 😉
Question about adding models
I wanted to use an OA2 tube regulator in a sim, so I found a model and added it to the library in the file library>cmp>standard.dio. Now when I run the sim it says it can't find the OA2 model. What am I doing wrong?
This is the model (it is modeled as a zener)
.model 0A2 D(Is=10u Rs=50 Cjo=10p nbv=147 bv=150 Ibv=20m Vpk=150 mfg=steve type=zener )
The sim does run fine if I change the OA2 callout to a zener number.
I wanted to use an OA2 tube regulator in a sim, so I found a model and added it to the library in the file library>cmp>standard.dio. Now when I run the sim it says it can't find the OA2 model. What am I doing wrong?
This is the model (it is modeled as a zener)
.model 0A2 D(Is=10u Rs=50 Cjo=10p nbv=147 bv=150 Ibv=20m Vpk=150 mfg=steve type=zener )
The sim does run fine if I change the OA2 callout to a zener number.
Go for it 🙂
If you look at post #1 you will see I have added a subsection to the index to cater for any submissions made by members.
Just post it all here (even if its in more than 1 post) and we can edit and tidy it up later.
THD calculation
Does anyone know how THD is calculated in LTSpice? Is it documented somewhere? Is it the rms sum of the 1st 10 harmonics or something else?
This came about as I noticed something strange. I have 2 circuits A & B, same Vout and frequency, A has higher harmonics h2 through h5 (as read from the Fourier plot) but lower THD than circuit B. Not a huge difference, but a lot more than could be explained by rounding errors, etc.
Does anyone know how THD is calculated in LTSpice? Is it documented somewhere? Is it the rms sum of the 1st 10 harmonics or something else?
This came about as I noticed something strange. I have 2 circuits A & B, same Vout and frequency, A has higher harmonics h2 through h5 (as read from the Fourier plot) but lower THD than circuit B. Not a huge difference, but a lot more than could be explained by rounding errors, etc.
If We could use your post as a hint, in one place you have said OA2 (letter O),
and in another place 0A2 (number 0). They aren't the same...maybe the same problem in your sim?
Aha! Yes indeed, I forgot that Oh-A-2 is really Zero-A-2, as in zero volts filament. Works now. Many thanks.
Not a THD calculator (sorry) but a resistor calculator, just one of the uses for a simulator (as a calculator). This was actualy an interesting problem, I wanted to calculate op-amp-gain-setting resistors for equal voltages (against ground) on both input pins. Demonstrates using the voltage-dependent-voltage-source 🙂
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Hi all,
Anyone have spice models for Intersil ICL8038CCPD and/or PTC PT2399? Thanks in advance.
That's the old Harris sine/triangle generator I believe. I'd think the chances of that having been modelled would be zero tbh.
Any thoughts on the PT2399? Someone had mentioned that there is believed to be some sort of "Delay object" in LTSpice. Ring a bell?
I doubt that anybody except an over-ambitious hobbyist would ever try to model that whole IC - there are just too many functional blocks inside it. It's been discontinued for quite a while but you can still find a few floating around: http://www.diyaudio.com/forums/swap...eform-generator-any-interest.html#post3482932
Dale
but you can probably find sims of each function block with generic spice transistor models
which while not the same as the integrated chip's Semi Process devices still can show operating principles
which while not the same as the integrated chip's Semi Process devices still can show operating principles
Question about adding models:
I did read your post #85 but it's not working for my issue so perhaps we need further clarification.
I added a triode by going to lib\sym\Misc and selecting the generic triode. Then on the schematic I changed "triode" to the actual one I want to use, let's say 6XX7. Then I added the directive .inc 6XX7.inc and stuck the model file 6XX7.inc both in the folder containing the sim and also in the folder lib\sub. Still, when I run the sim it can't find the model. What am I doing wrong?
I get the error "Unknown subcircuit called in"
I did read your post #85 but it's not working for my issue so perhaps we need further clarification.
I added a triode by going to lib\sym\Misc and selecting the generic triode. Then on the schematic I changed "triode" to the actual one I want to use, let's say 6XX7. Then I added the directive .inc 6XX7.inc and stuck the model file 6XX7.inc both in the folder containing the sim and also in the folder lib\sub. Still, when I run the sim it can't find the model. What am I doing wrong?
I get the error "Unknown subcircuit called in"
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check file, subckt name, spelling?
you can also just put the .subckt in the schematic with the Spice Directive button
you can also just put the .subckt in the schematic with the Spice Directive button