D Flip Flop
As we have seen in the SR flip flop when the inputs S= R are applied the forbidden or indeterminate state occurs. This state can destabilize the SR file flop. It can be avoided by D flip flop. The D flip flop can be constructed using SR flip flop. The D flip flop has one inputs D and a clock inputs. The logic diagram of D flip flop is shown in figure.
The D input is directly connected to the S input and its complement is connected to R input. since the output is delayed because the output does not change immediately when the clock pulse goes from 0 to 1 the inputs is thus delayed by a clock pulse before appearing at the output. So it is also known as delay flip flop.