Data Sheet

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32. Electronic ‘AND’ Gate
Build the circuit, turn on the switch (62) and the
press switch[61] and you will light up the lamp (76).
In digital electronics there are seven logic gates:
AND, OR, XOR, NOT, NAND, NOR, and XNOR. This
circuit represents an AND gate. If ON = True and
OFF = False then an AND gate is best dened as:
The output is TRUE only when both inputs are True.
Therefore, the two inputs represented by the press
switch (61) and the switch (62) must both be ON
(TRUE) in order for the output represented by the
lamp (76) to be ON (TRUE).
33. Electronic ‘OR’ Gate
Build the circuit, turn on the switch (62) or press
the press switch (61) and you will light up the lamp
(76). If you want to turn off the lamp (76), you have
to disconnect both the switch (62) and the press
switch (61). This circuit represents an OR gate. If
ON = True and OFF = False, then an OR gate is best
dened as: The output is TRUE when any input is
True and False only when all the inputs are False.
In this circuit the output represented by the lamp
(76) is ON (True) if either input represented by the
press switch (61) or the switch (62) or both is ON
(TRUE). The lamp (76) is OFF (False) only when both
switches are OFF (False).