Different Types Of Flip Flops | SR, D, JK & T FlipFlops With Truth Table
A flip flop is a basic memory unit capable of storing one a single bit at a time. It is made from two latches in Master-slave configuration. They are edge sensitive so they are triggered by a clock pulse.
There are few types of flip flop which are given below.
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SR Flip Flop
The name SR represents the SET and RESET function of the flipflop. This type of flip flop has two inputs named S & R for SET & RESET respectfully & and two outputs name Q & Q’, whereas Q’ is the invert of Q.
The SET function represents when output Q is high & Q’ is low. RESET function represents clear function when output Q low & Q’ High.
At each trigger pulse, the output of SR flipflop sets when the input S is high and input R is low. And clears the output when the input R is HIGH & S is low.
when both inputs R & S are LOW, the output status Q & Q’ Remains unchanged.
Both HIGH input combination is considered forbidden (invalid) as they will produce race condition (indetermined state) which causes ambiguity in the system.
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D Flip Flop
You can say that D flip-flop is a modified form of SR flip flop because design-wise, D flip flop is the same as SR flip flop with only a minor change. In D flip-flop, the inputs of SR flip flop are combined together into a single input D with one of the input R inverted.
This configuration eliminates the invalid inputs combinations as there cannot be the same inputs.
During the clock pulse, D flipflops SET output when its input is High & Resets when the input is LOW. It is easier to configure as compared to SR Flip flop because there are no Invalid inputs.
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JK Flip Flop
JK flipflop can also be considered a better and modified version of SR flip-flop with J input corresponding to SET and K input corresponding to RESET of the JK flipflop. The invalid inputs of the SR flip-flops are used in this type of flipflop for a meaning full function.
When both inputs are high the output status is toggled during each clock cycle. When the inputs are same, the JK flip-flop retains its original status even after clock pulses.
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T Flip Flop
The T in the name of T flip-flop represents the toggle function of the flipflop. It is a modified version of the JK flipflop. The input of the JK flip-flop is combined together into one same input named T input.
This single input enables the flipflop to toggle its status whenever its input T is high during each clock pulse. And also it retains its status when the input T is Low.