74HC08 (Quad 2 Input AND Gate) Not working

#1 · October 12, 2025, 10:15 am

I tried to simulate counter circuit and 74HC08 is one of the component used. After starting simulation, I see input 1A and 1B both HIGH but output 1Y is LOW, can anyone point out what I did wrong?

Uploaded files:

Counter-test.sim1

#2 · October 12, 2025, 10:52 am

Hi.

The problem is that LEDs don't have resistances so they keep voltage quite low.
Add resistances or set "Resistance" property in LEDs to at least 50 Ω.

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#3 · October 12, 2025, 11:04 am

Thank you so much! You save the day!