issue using proteus

Thread Starter

m4lyg0s

Joined Apr 17, 2014
11
hello there i am new in this forum but i´m planning to stay here for a long time :p.

i have an issue with proteus, i am trying to simulate a triangule wave using 2 opamps (tl082) one as an integrator and the other as a square wave generator

originally i thought it was a bug from proteus but well i saw on youtube and others source of reference that it should not give anyproblem... after that i tried falstad and it is working with no issue

i am posting an image showing both simulations

can you guys help m find this problem please?, is it telling me that the slew rate is to low for the frequency i want it to work with?

for what purpuse i am doing this triangle generator , well i will use it to compare it with signal from either a ldr or a phototransistor (ofc both signal will be converted to voltage) and generate a pwm to move a pair of dc motors

i was thinking of using a timer 555 but i am working with voltage (as far as i investigate timer 555 pin 5 is for vco and not pwm)

finally , i know there are components like LTC6992 that just work how i want XD. but it is not on sale(?) at the "markets" i am familiar with and buying at digikey well cost too much time



i am uploading the file if there is someone ready to test it please. (as a side note change the extension from .txt to .pdsprj)

and i am sending the link from falstad if you are interested in it too

http://www.falstad.com/circuit/#$+1...+16+160+0 o+12+64+0+34+10.0+9.765625E-5+0+-1


thanks for your time trying to understand me and love :)
 

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Thread Starter

m4lyg0s

Joined Apr 17, 2014
11
hello there it is me again though i got no help i was able to "fix " it, searching in the forum i found someone having almost the same issue .

this is the link,
http://forum.allaboutcircuits.com/showthread.php?t=40627&page=4

thanks to gatorcpe´s schematic and marsden pointing the main issue (histeresis and the opamp itself) i got my generator to work though it is still not working in proteus it is working in multisim and in real life

the next step of my project is to comparate that triangule wave with a signal provided by 2 phototransistor (im using tl082 in mode transimpedance) it is working so far :), though details ill be able to see tomorrow

as a sidenote the light those phototransistor are getting is laser redirected via optic fibers

cheers to everyone
 

DrRich

Joined Apr 21, 2014
5
Pfft. Forced to use Proteus? It is one of the better offerings! (at least UI makes sense, unlike Eagle :D). My productivity in Proteus is very good compared to anything else and I have use a fair share of products (Protel 99SE, CadStar, OrCad, er Agilent ADS and others).

With a lot of oscillator circuits, you need to give them a little "kick" to start them up in simulation. Often, I do this by attaching a high value resistor from the oscillators timing components (100k ish or more - higher is preferable) to a stimulus that generates a singular pulse at the beginning of the simulation.

Unless you do this, pretty much all oscillators in Proteus refuse to start.

Try it out, even the classic 7414 oscillator does not work in proteus unless you give it a little kick at the beginning of the simulation.
 

Thread Starter

m4lyg0s

Joined Apr 17, 2014
11
well i am not force to use any of them , if i know how to use them , use it thats what my teacher said .-. , what you miean to kick in so the generator work? , you mean use a switch or a button ? i tried that too , instead of a button i played with a potentiometer conected to vcc , gave me lot of warnings : transient gmin , singular matrix check node , and not running in reall time due to excessive cpu load XD
 

DerStrom8

Joined Feb 20, 2011
2,390
Multisim and Proteus are the only two simulators I use. I am very impressed with them both and would never use anything else. I have used LTSpice and PSpice but was not terribly impressed.
 

Thread Starter

m4lyg0s

Joined Apr 17, 2014
11
spice was the 1st reason i have to commit suicide more than twice... and THAT was an obligatory software to learn ,jesus....
 
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