Thanks
I can see the original 4069 circuit here.....................
I have the Library CD4000_v.lib.
From your demo the duty cycle is tiny.
How can this be increased in this circuit?

 

Thanks
I can see the original 4069 circuit here.....................
I have the Library CD4000_v.lib.
From your demo the duty cycle is tiny.
How can this be increased in this circuit?

Hi

It’s not my circuit, and I didn’t really study it much.
But it looks to be a leading and trailing edge detector. The resulting duty cycle will depend on input frequency. Try changing C1/R1 and/or C2/R2 time constants.

eT

 

Thanks to all
Primarily I am here to learn.

I have a story.

20 years ago I went to the Hanoi university to learn Vietnamese.
For white devils, like myself, this is very very difficult.

After a lot of hard study I realized that the only Vietnamese people that could understand what I spoke were Vietnamese people that spoke English. Extremely useful NOT!

I see an analogy with this forum.

When a novice asks a questions the experts here have no real idea of the position of ignorance the novice is speaking from.
The answers provided tend to be "club speak" ie expert to expert. The poor old novice is drowned in unfamiliarity and alien terms.

I understand that the quality of the answer is determined by the clarity of the question.

But when you don't speak the language how can one ask precise questions.

Instead of trying to make us feel guilty about how we discuss things, why not ask for clarification on whatever part is troubling you. If you're not getting anything at all out of any of these answers, you may want to take a few steps back and build some more fundamentals before trying to simulate integrated circuits. However, I suspect that's not the case, and that you're exaggerating and being a little dramatic.

So, what's the trouble?

It is quite common, both in printed schematics and in simulation software, for the power connections to integrated circuits (logic chips, op amps, microcontrollers, etc.) to not be shown at all, or to be represented somewhere else in the schematic. This cleans up and clarifies things, making it much easier to see the logic/signal flow without distractions.

There isn't any one correct way that this is handled. We can't be much more specific without referring to a specific example. Sorry, there just isn't a simple answer to precisely how this is handled - the details are situation specific.

If it's the simulation side of things you're struggling with, tell us what part you're struggling with. What do you have so far? What is the simulator doing or not doing? What's the hang up?

We'd love to help, but you've got to do more than just complain that we're talking over your head. We've all been there, and all of us have gotten help as we learned. We're here to share what we've learned, but we can't guess what you need. Help us help you.

 

Thanks to all
Primarily I am here to learn.

I have a story.

20 years ago I went to the Hanoi university to learn Vietnamese.
For white devils, like myself, this is very very difficult.

After a lot of hard study I realized that the only Vietnamese people that could understand what I spoke were Vietnamese people that spoke English. Extremely useful NOT!

I see an analogy with this forum.

When a novice asks a questions the experts here have no real idea of the position of ignorance the novice is speaking from.
The answers provided tend to be "club speak" ie expert to expert. The poor old novice is drowned in unfamiliarity and alien terms.

I understand that the quality of the answer is determined by the clarity of the question.

But when you don't speak the language how can one ask precise questions.

The secrets to learning are persistence and paying attention, and in a venue such as this one that can certainly work. But sometimes there is a need to restate the question. I have asked that in a number of instances, requesting a better explanation of just what the original poster was seeking to discover. Your question was valid, as was my answer, but it did not fit your question.
The fact that this site does have a lot of really knowing folks is great, although as you commented, they are experts talking with experts. But that can be a source of education even if it is far beyond what you were seeking. Sometimes you need to ask "What is the mechanism for it being that way?" Getting answers to that sort of question will bring insight and understanding, both are very valuable.
So don't give up on us yet, just consider that some questions may need to be clarified as to just what it is that you need to know.

 

Thanks, I have had a go at this.
I did not copy exactly so I did not use "user defined" parameters in V1.
I could not understand your "Rser=100m"

I am still confused with the two wires going into U1F despite no obvious connection points there.

My variant on your theme FAILED. I obviously missed something major.

Your comments please

 

When a novice asks a questions the experts here have no real idea of the position of ignorance the novice is speaking from.

Unfortunately, often true; but not always. And usually when a thread starts to wander off, the TS (that's you) can gently ask people to get back to his level. The good people do, the rest you can ignore. There is a frequent poster in another forum who regularly tells less experienced people to come back in twenty years and they might understand his answers. This forum has less of that attitude than most, so hang in and keep asking.

ak

 

My variant on your theme FAILED. I obviously missed something major.

Maybe not major but certainly significant.
Change the 0.22pF (tiny) caps to 22pF as in the original.

 

Maybe not major but certainly significant.
Change the 0.22pF (tiny) caps to 22pF as in the original.

I have done this and made another correction.
Missing .param statement.
It now has life.
If the remaining neurones can continue working as a team I maybe able to massage it to where I need it.

Thanks

 

Missing .param statement.

You don't need the .param statement since you put all the pulse parameters directly into the pulse statement.

 

Thanks
Ignorance is a very boring place.

 

I have done this and made another correction.
Missing .param statement.
It now has life.
If the remaining neurones can continue working as a team I maybe able to massage it to where I need it.

Thanks

LTSpice has a steep learning curve (at least it's felt that way to me) and can be frustrating at times, but the payoff is well worth the effort. It sounds like you're making progress. Keep up the good work!

 

Thanks to all
Primarily I am here to learn.

I have a story.

20 years ago I went to the Hanoi university to learn Vietnamese.
For white devils, like myself, this is very very difficult.

After a lot of hard study I realized that the only Vietnamese people that could understand what I spoke were Vietnamese people that spoke English. Extremely useful NOT!

I see an analogy with this forum.

When a novice asks a questions the experts here have no real idea of the position of ignorance the novice is speaking from.
The answers provided tend to be "club speak" ie expert to expert. The poor old novice is drowned in unfamiliarity and alien terms.

I understand that the quality of the answer is determined by the clarity of the question.

But when you don't speak the language how can one ask precise questions.

Sorry for chiming in since I cannot reply but to the most basic of your question. I am afraid your are creating a problem of what is just what happens everywhere in life.

As a professional newbie myself, I learnt that no matter what I ask (obviously because I ignore something) I have to accept that the answer could contain information still hard to grasp. Knowledge gaining is, for me, climbing a ladder with few quantum leaps if at all.

Regarding eventual digressions, focus on your problem and ignore the rest. Imagine a conversation while in a group of friends. Would you expect all of them talking precisely about the subject?

Ability is to stay in focus and avoid digressions. In my daily work is what I care of all the time and is worth the effort.

Buena suerte.

EDIT/ Where is that Darwin? Not in Argentina, I guess. /EDIT

 

Thanks, I have had a go at this.
I did not copy exactly so I did not use "user defined" parameters in V1.
I could not understand your "Rser=100m"

Yes...I make it a habit of using some resistance in voltage sources because in reality all voltage sources have some resistance.
And yes...I also use parameters for voltage sources used for power supply and logic levels so they can be changed easily.
Especially with CD4000 chip simulations.

I am still confused with the two wires going into U1F despite no obvious connection points there.

Those represent the IC power supply connections. I showed them because they were on the original drawing.
But they also illustrate use of bypass caps....many time they are forgotten.

My variant on your theme FAILED. I obviously missed something major.

I think the only thing you missed was the capacitor sizes. Should have been 22 pico farad instead of 22 femto farad.
These were the only values I changed in your simulation and the sim worked.

eT

 

Thanks, I have had a go at this.
What is challenging is that mostly the actual circuit in logic gates is fairly complex, and mostly what one would find is a whole lot of circuitry that may vary between different manufacturers for the same IC.number. Most of the time that makes no difference, but in one instance I did a design that would work with National brand CD4538BE devices but was totally unreliable with Motorola "equivalent" devices. At least I think those were the two brands. My whole point is that the insides of even just an inverter are not trivial, and if you move to a schmidt trigger inverter the internal circuit is a bit confusing. So because the power supply normally does not connect directly to inputs or outputs it is simply understood to somehow supply the charges that they deliver and consume. If you can get hold of some 1972 or73 CMOS logic device manuals you will be able to see the circuits and what I was referencing.
And I hope that this long drawn out explanation has delivered a little bit of value.

 

Hay más de un Darwin
Este no está en Argentina.
Territorio del Norte - Australia

If I have learnt only a single thing it would be to keep my gob shut.

 

I am still playing with capacitance values.
I have to balance between the min frequency and max frequency this device will be confronted with and try to maintain the duty cycle below 50% and not less than 10%. So now I am a random number generator