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This problem in JK FF is called racing problem and this condition is called race-
around condition. The racing problem can be avoided by using JK Master Slave (JK MS)
flip-flop or by using edge triggering techniques.
3.1.4 JK Master Slave (JKMS) flip-flop
The racing problem in JK FF can be avoided by using JKMS FF. The logic symbol of
JKMS FF is show in figure.
Figure : Logic symbol of JKMS FF
In JKMS FF there are two JKFFs, one Master JKFF and one Slave JKFF. The CLK
pulse of the master section is inverted and then given to the CLK input of the slave section.
Figure : JKMS FF using two JK FF
The logic circuit diagram and truth table of JKMS FF are shown in figure.
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