Logic gates NOR (4001, 4025, 4002, 7402, 7427)
Logic gate ΝΟR (NOT OR)
The logic gate NOR is a combination of the gate OR and of the gate ΝΟΤ. The logic function that describes the gate NOR is: Υ = (Α + Β)'
Its symbol is the same as the one of the gate OR but a small circle is added that indicates a denial. The truth table and the symbol can be seen at the following figure:
The output of the gate NOR is 1 when all of the inputs are 0
Logic gates NOR CMOS CD4001, CD4025, CD4002
Logic gates NOR CMOS 74HC02, 74HC27
Logic gates NOR TTL compatible 74LS02, 74LS27, 74HCT02, 74HCT27