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.
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.
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.
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.
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.