How To Avoid Race Around Condition in JK Flip Flop
Race around condition is the most important condition in Digital electronics. In J-K Flip flop, when J=K=1 the output changes its state. When a clock pulse width tp is applied the output will change from 1 to 0 after a time interval of Δt, where Δt is the propagation delay through two NAND Gates in series. Now after Δt we have J=K=1, Q=0, After another interval of Δt, output Q will become 1. Hence the output will oscillates back and forth between 0 and 1 in the duration tp of the clock pulse width.
So at the end of the clock pulse the value of Q is ambiguous. This situation is known as Race Around condition.
This condition can be avoided if [tp < Δt < T] as shown in figure. Lump delay lines can be used in series with fee back connections in order to increase the loop delay beyond tp and hence to prevent race around difficulty. However it may be difficult to satisfy this inequality, because of very small propagation delay in Integrated circuits (IC's). This Race around conditions can be avoided in Master Slave Flip flop.
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So at the end of the clock pulse the value of Q is ambiguous. This situation is known as Race Around condition.
This condition can be avoided if [tp < Δt < T] as shown in figure. Lump delay lines can be used in series with fee back connections in order to increase the loop delay beyond tp and hence to prevent race around difficulty. However it may be difficult to satisfy this inequality, because of very small propagation delay in Integrated circuits (IC's). This Race around conditions can be avoided in Master Slave Flip flop.
EAM6XYQWZG72
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