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D Flip-Flop Truth Table


D Flip-Flop Truth Table

D Flip-Flop Truth Table

A D Flip-Flop (Data Flip-Flop) transfers the input D to output Q on the triggering clock edge.

Truth Table (Positive Edge Triggered)

Clock (CLK) D (Input) Q (Next State) Description
↑ (rising edge) 0 0 Reset
↑ (rising edge) 1 1 Set
No edge X Q (no change) Holds previous value

Simplified Table

D Q (next)
0 0
1 1

Summary

  • On clock edge: Qnext = D
  • Without clock transition: output remains unchanged
  • Eliminates invalid states of SR flip-flop
D = Data → Q copies D on clock

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