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Hello, im a newbie with some questions.


Jun 30, 2023
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Hello people. I recently made some circuits in Proteus 8 and in tinkercad.
I would be grateful if someone could help me compare these two circuits.
They are supposed to be the same but I don't know if they are both correct.

Circuito 555 2.png
Circuito 555.png

Some commeents about your post in general,
A forum is meant that many people gain information from your post.
Thus your headline should be a short description of the real problem. Otherwise no one finds your post ... and maybe starts a very similar thread.

These thinkecad schematics are hard to read - at least for me.
I know thinkercad is used by many hobbyists. But they do it a very unprofessional way .... and teach you thing that you need forget later when you become more professional. Thus I recommend to learn to do it the professional way ... to avoid to need to learn things twice.

(Sadly) In opposite to simulations, in real world a capacitor at VCC is mandatory in most cases. Thus I recommend to add this in your achematic, so you can' t forget to add it on the real circuit.

The proteus schematic has low resolution, thus the values are hard to read.

The wiring of the thinkercad is unnecessarily difficult ... and due to crossing of same colored wires hard to read.
Example: pin 8 of IC is VCC, so the usual way is to use one wire at column 4 to the common VCC line (and omit the second gren wire)
Same with GND.

As pointed out by KlausST, the thinkercad circuit uses too much wires. In any case it is different from the schematic since two connections are missing: there is no wire between pin 2 and 6 and pin 4 is not connected to Vcc (it's not connected at all).
In general the LED have to be connected to the output of the NE555 through a resistor to limit the current otherwise the LED will be damaged.
Usually a blue LED has a voltage drop of 3.5V and requires a current of 25mA, then if you supply the 555 with a 15V battery, then the resistor in series to the LED will be:

R = (15-3.5)/25m = about 470 ohm

Probably the output voltage of the 555 will be less than Vcc, so you could recalculate the resistor based on the actual value or the LED will be little bit less brigth.
Respectifully, the circuit in the left is a real mess, hard to assess; a lot of wires conected to other wires.
Clean routing protects the circuit from ourselves, making it easy to review.

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