Subject
Year
: Digital System
: 2009
Logic Gates
Chapter 5
Overview
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The Inverter
The AND Gate
The OR Gate
The NOR Gate
The Exclusive-OR & Exclusive NOR Gates
Timing diagram
3
The Inverter
• The inverter (NOT circuit) performs the operation called inversion or
complementation. The inverter changes one logic level to opposite level. In terms
of bits, it change a 1 to a 0 and a 0 to a 1
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The Inverter Logic
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The AND Gate
• The AND gate produces a HIGH output only when all of the inputs are HIGH
.When any of the inputs is LOW, the output is LOW.
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The AND Gate logic
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The AND Gate Example
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The AND Gate Example con’t
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The AND Gate Application
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The OR Gate
• An OR gate produce a HIGH on the output when any of the inputs is HIGH. The
output is LOW only when all the inputs are LOW.
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The OR Gate Logic
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The OR Gate Example
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The OR Gate Application
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The Exclusive-OR Gate
• The output of an Ex-OR gate is HIGH only when the two inputs are at the opposite
logic level.
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The Exclusive-NOR Gate
• The output of an Ex-NOR gate is LOW only when the two inputs are at the
opposite logic level.
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