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enter image description here

I am using the 74HC08N chip. Why doesn't the first AND gate latch itself?

I have connected the output of the first AND gate to its own input.

I have used two resistors, the one on top is a pull-up and the one in the bottom is the pull-down

After I release the button, the diode should take care by feeding the current from the output back into the input. Why doesn't this happen. The LED is not always turned on after I press the button once.

enter image description here

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  • \$\begingroup\$ please draw the schematic diagram of the circuit \$\endgroup\$
    – jsotola
    Commented Jun 24, 2021 at 6:18
  • \$\begingroup\$ Where is your decoupling? \$\endgroup\$
    – winny
    Commented Jun 24, 2021 at 6:23
  • \$\begingroup\$ Those prototyping boards often are quite bad and gives you lots of bad contacts. \$\endgroup\$
    – Damien
    Commented Jun 24, 2021 at 6:31
  • \$\begingroup\$ @jsotola i have added a picture \$\endgroup\$
    – Kandy boy
    Commented Jun 24, 2021 at 6:39
  • \$\begingroup\$ @winny i am not sure what decoupling means , what is it actually ? \$\endgroup\$
    – Kandy boy
    Commented Jun 24, 2021 at 6:39

1 Answer 1

Reset to default
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you must connect the LED through a resistor to the ground:

enter image description here

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  • \$\begingroup\$ Thank you very much @Paul Ghobril, your solution worked perfectly ! \$\endgroup\$
    – Kandy boy
    Commented Jun 24, 2021 at 14:20
  • \$\begingroup\$ @Kandyboy - Hi, Your comment suggests that you have received as much help as you need. In order to mark the topic as solved, please consider "accepting" the answer which most helped you (i.e. click the "tick mark" ("check mark") next to that answer, to turn it green). Although accepting an answer isn't mandatory, it is encouraged to do so as your question is then clearly shown as being answered in various lists, it shows that you aren't waiting for more answers, and we don't get nagged for it being a question without an accepted answer. Thanks! \$\endgroup\$
    – SamGibson ♦
    Commented Jan 8, 2022 at 20:07

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