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schematic

simulate this circuit – Schematic created using CircuitLab

I have this schematic that I need to convert to a circuit using Tinkercad. At the moment, the LED turns on but it does not flash and I can not figure out why.

Here is the tinkercad Link

Schematic:

enter image description here

Circuit:

enter image description here

Grewal_Creator
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  • Please edit your question and insert the schematic directly into the question rather than linking to an external site. Stack Exchange hosts its own images. – jwh20 Jun 01 '21 at 15:00
  • You might want to consider avoiding 555’s when it can be done much simpler https://electronics.stackexchange.com/questions/313415/rc-circuit-as-clock-source/313420#313420 then subst. The same RC values 10uF 51k – Tony Stewart EE75 Jun 01 '21 at 15:19
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    Pin 1 (GND) of the 555 looks like it is going to the wrong side of the capacitor – Mat Jun 01 '21 at 15:24
  • Ive fixed the 555 to ground issue and it doesnt seem to have changed anything – Grewal_Creator Jun 01 '21 at 16:04
  • The ratio of your resistor values determine the on time vs the off time. Your 1k off time is so small that the LED appears to be on all the time. – Audioguru Jun 01 '21 at 17:31
  • @Audioguru The cap discharges through 51k, not 1k. – Mitu Raj Jun 01 '21 at 19:28
  • Looks like your schematic and 'breadboard' diagram are apple and orange. Re-check the connections. – Mitu Raj Jun 01 '21 at 19:33
  • it all looks good to me, perhaps you have the wrong resistor in r2 – Jasen Слава Україні Jun 01 '21 at 21:21
  • @ Mitsu Raj No, the capacitor charges slowly through 52k (with the LED turned on) then the capacitor discharges very quickly through 1k with the LED turned off for such a short off duration that it appears to be turned on all the time. – Audioguru Jun 02 '21 at 01:45
  • @Audioguru I am afraid it's actually the otherway. R2 for discharging and R1+R2 for charging. https://www.electronics-tutorials.ws/waveforms/555_oscillator.html – Mitu Raj Jun 03 '21 at 19:53
  • I see that the LED off-time should be almost the same as the LED on-time. Then if the parts are good the breadboard must have an intermittent contact. – Audioguru Jun 04 '21 at 22:50

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Your 555 isn't grounded. The only connection to ground in the entire circuit is the one connecting the LED to ground, and the 555 isn't connected to that. At least if your cartoon diagram is anything to go by.

Hearth
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