Troubleshooting a Three Input AND Gate Circuit

  • Thread starter Thread starter kenvin100
  • Start date Start date
  • Tags Tags
    Gate Input
AI Thread Summary
A user faced issues with a three-input AND gate circuit on a breadboard, where the first LED lit up but the second did not. After confirming that pins 1, 2, and 5 were connected to the positive line, the user realized the problem stemmed from a broken circuit caused by an extra input connected to pin 4. Once the extra wire was removed, the circuit functioned correctly, and both LEDs lit up as intended. The discussion highlights the importance of careful connections in circuit design. Troubleshooting steps led to a successful resolution of the issue.
kenvin100
Messages
8
Reaction score
0
Okay, so I am trying to use the breadboard and I have a hard time with a three input AND gate. Guess I can do a schematic

http://imageiso.com/out.php/i17298_3inputandgate.JPG

So in my bread board, I have pins 1 and 2 as inputs..with pin 3 as a LED (output), and I have a jumper connecting pins 3 and 4 cause the result of the first and gate determines if the second AND Gates lights the LED..and I have pin 5 as the input..and pin 6 in another LED..now I connected pin 7 to the ground and pin 14 to +5V..this is the problem: the first and gate works..first LED (on pin3) lights up, but the second one doesnt

I tested everything and I reconnected it to my breadboard..sorry I don't have a picture of it so I am curious why the second one won't light up..Any ideas guys?
 
Last edited by a moderator:
Physics news on Phys.org
So... do you have pins 1, 2, and 5 all tied high?

- Warren
 
yes i did that..its all on high..like on the +ve line..where pin 14 is connect to +5..and i have another wire connected to the power source..well the first led works

and I tried another LED..so I really don't know what I am doing wrong
 
How exactly have you connected pin 3 to both an LED and to pin 4?

- Warren
 
nvm i fixed it.apparently i think i broke the circuit when i added an extra input to pin 4..i just removed that wire and it worked..
 
Back
Top