Manual

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I
f you don’t know what an exclusive OR means,
don’t worry. An exclusive OR (abbreviated XOR)
circuit provides a high output only when one or the
o
ther of its inputs are high.
You can see that an XOR circuit produces a low
output, only if both of the inputs are the same (high
or low). If the inputs are different (either high and
low or low and high) it results in the output being
high. This circuit is handy to let us know if we have
two inputs that are the same or if the inputs are
different.
Before completing this circuit, be sure you have the
switch set to B. Once you have finished connecting
the wiring, connect terminals 13 and 14 to turn the
power on. Now watch LED 1. Press the key to
produce a high input. Is there any change in the
LED 1? To make both inputs low release the switch.
To make the input through the switch high, set the
switch to A. What does LED 1 do?
Press the key while leaving the switch at A to make
both the inputs high. Now you can see that in an
XOR circuit, you need two high inputs to produce a
low output.
If desired, you can build an XNOR circuit (exclusive
NOR). We will not build one here, however, you
might be able to figure how to do it. Hint: It is almost
identical to the NOR circuit followed by additional
wiring in order to reverse the circuit. Make sure that
you keep track of your experiments in your
notebook, particularly if you make an XNOR circuit.
N
otes:
EXPERIMENT #33: “EXCLUSIVE OR” DTL CIRCUIT
Wiring Sequence:
o 13-45-132-137
o 14-119
o 44-31-75
o 76-84-82-33-121
o 81-40-138
o 41-130
o 48-42-128
o 43-47
o 46-80
o 79-129-125
o 83-126-127-131
Schematic
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