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Pspice and 4538 help

Hello!
I'm trying to simulate a monostable multivibrator MC14538B or CD4538B in PSpice. I'm butting heads with this program for the second day and can't seem to make it work.
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Is there anything better than PSpice? Because I've grown to despise this program.
 

Harald Kapp

Moderator
Moderator
Welcome to our forum.

I can't help you with PSPICE, but is this PW=0,5m? Shouldn't this read PW=0.5m?
Also: is there a connection from R1/C1 to UA1? You show a wire, but there is no connecting dot (this may be a visual problem, check the netlist).
 
Hey!
There's a connection there, dunno why it shows that there isn't. And yeah, I changed the dot in 0.5 right away. Also, CX (1) shouldn't have anything connected to it.
It turns out you have to load specific model libraries. I don't have one that says 4538. I tried loading the likes of 1-shot.lib but that didn't really help. The simulation still says "unspecified model" or something like that.
Anyway, I found a different program called LT Spice IV and simulated the circuit without too many problems. The program itself is not very user-friendly, unfortunately. Even though it doesn't require any tinkering with libraries, you can't use keyboard shortcuts, copy/paste also doesn't work.

Do you know any good programs for simulations, that are relatively easy to use? Even if they are not free.
 
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Harald Kapp

Moderator
Moderator
Even though it doesn't require any tinkering with libraries, you can't use keyboard shortcuts, copy/paste also doesn't work.
It does require tinkering with libraries - if the model you need is not included.
A lot of keyboard shortcuts are available and one can become acquainted quite fast with the program. See our ressources forum, there I have put lots of useful ressources for using LTSPICE.

Regardless of the simulator you use, you will always have to find suitable models for the components you want to simulate - or build your own model.
 
I meant that if a model exists in LTSpice, and I can place it on the board - it will simulate (Unlike PSpice, but maybe I'm wrong). I found a large library collection on the internet ("vanilla" LTSpice doesn't have a lot of models).

Thanks for your replies :) I will go look through the resources forum.
 
Do you know any good programs for simulations, that are relatively easy to use? Even if they are not free.

Don`t blame the program. Since more than 20 years I work with PSpice - and if something went wrong it was ALWAYS a failure of the user (that`s me) and NEVER a malfunction of the program.
May I ask: What means "can`t seem to make it work"?
Didn`t the program start? Was there any failure message? Are the resullts non-realistic?
Without any information about how the program does react I cannot give any recommendation.
By the way: I share your opinion about LTSpice.
 
Well, I built the exact same circuit (with some changes that are not present in the picture, like not connecting anything to CX) in LTSpice and it worked without a problem. PSpice wouldn't simulate it because of "unspecified model" error or something similar.
 
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