- A pulse-triggered flip-flop is also called “master-salve” due to its implementation which
require two D-type flip-flop in a master-salve set up as shown below:
The D flip-flop is the most commonly used bi-stable memory device. The other two kinds used are J-K
and T flip-flops.
J-K Flip Flops
Below is a negative-edge triggered JK flip flop. As in other flip-flops, the inputs J and K are called
“excitation inputs”.
S
1J
C1
1K
R
PRE’
J
CLK
K
CLR’
Q
Q’
J K Q + Comment
0 0 Q no change
0 1 0 reset condition
1 0 1 set condition
1 1 Q’ toggle
Symbol
Characteristic equation: Q
+
= J.Q’ + K’.Q
Characteristic Table
Q
D
C
S
D
C
R
C
D
Q
Q
Q’
Set
Reset
or
S
D
C
R
Q
Q’
Set
D
C
Reset
Postponed output symbol