Page 83 - Digital Electronics by harish
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Level triggering
In this triggering, the output of the FF changes during the presence of the clock signal.
When the inputs to the FF change during the presence of the clock pulse, uncertainty
in the output occurs. This problem can be avoided by using Master-Slave FFs or edge
triggered FFs.
Edge triggering
There are two types of edge triggering:
1. Positive edge triggering
2. Negative edge triggering
Figure : Positive edge triggered FF
Figure : Negative edge triggered FF
In Positive edge triggering, the output of the FF changes only during the positive edge
(leading edge) of the clock pulse. In negative edge triggering, the output of the FF changes
only during the negative edge (trailing edge) of the clock pulse. The type of triggering of FF
is represented in the clock input as shown in figure.
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