Simple OR Gate with LED.
Shows the working of an OR gate with a 5v source.
I used 2 pulldown resistors to give the OR gate the LOW input when the switches are open, otherwhise they would be floating and weird things can happen.
Such as the OR gate detecting a high input when floating, making the LED turn on even when the switches are open.
The OR gate OUTPUT turns HIGH when "at least" 1 of the INPUTS is HIGH.
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Please bare in mind (altough not showing here) that besides the INPUT and OUTPUT pins the OR gate also has VDD (5Volt) and VSS (Ground) pins which need to be connected to 5 Volts and GROUND.
This OR gate would have 5 pins.
1 VDD (5volts)
2 VSS (Ground)
3 Input pin.
4 Input pin
5 Output pin.
The OR gates come in a variety of "packages" (ic's). For example a OR Gate with 3 or 4 INPUTS.
There are also IC'S with 2 or more OR Gates on 1 IC.
