# Master-slave vs jk flipflop [duplicate]

This question already has an answer here:

I'm trying to figure out what's the difference between a master-slave flip flop and a jk flip flop with the clock negated.

Do they behave in the same manner?

can I just say that a master slave flipflop is a flip flop which output id giben in the falling edge but recorded in the rising edge?

## marked as duplicate by Mitu Raj, Michel Keijzers, Kevin Reid, winny, Dmitry GrigoryevMay 8 '18 at 8:48

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## 1 Answer

A JK flip flop with the clock negated has the truth table for a normal JK flip flop, however with the clock negated, the outputs are shifted by half of a clock cycle.

A master slave flip flop looks like this:

Source: Circuits Today

If you look at the truth tables for both, there isn't much difference. However looking at the gates of the negated clock input, Q can change at the same time as the clock and create a race condition. With the delay of the extra gates in the Master Slave JK flip flop this is not possible and prevents race conditions.