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555 LED Circuit not playing nicely

jokester2001101

Jan 14, 2023
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Jan 14, 2023
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Im having issues with my 555 circuit not working how the math should. i need the led on for 5-7seconds and off for 50-60 seconds. it just doesnt seem to be cooperating. any help with my diagram below?

1673677806379.png
 

bertus

Moderator
Nov 8, 2019
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hello

the reset pin should be connected to the plus of the powersource
also you will need a current limiting resistor for the led
without the resistor, the 555 can push upto 200 mA into the led and burn it

bertus
 

danadak

Feb 19, 2021
751
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Keep in mind the tolerance of electrolytic is awful, in some cases > 100%,
so if timing off first suspect assuming you use 5% or better R's. Add to that
timing accuracy CMOS 555 is ~ +/- 10% (ideal R and C).




Regards, Dana.
 

Alec_t

Jul 7, 2015
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Leakage current through C1 can be a problem with time periods longer than a few seconds.
 

crutschow

May 7, 2021
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Your schematic is very hard to follow with horizontal components and long wires with jogs.
Please draw it with vertical components and short wires with minimum jogs.
 

jokester2001101

Jan 14, 2023
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Jan 14, 2023
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Your schematic is very hard to follow with horizontal components and long wires with jogs.
Please draw it with vertical components and short wires with minimum jogs.
i dont know the best way to draw. i found the program online for free
 

Bluejets

Oct 5, 2014
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Bat1+ and Bat1- are connections to power source, battery.


Regards, Dana.
Rather strange to show that when the battery is already shown.
As is, it infers there is more to the circuit than shown.
 
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