The D Flip Flop

We want a FF that responds to a clock edge, either rising or falling. One design is the master-slave type, Figure 62.

**Figure 62:** Master-slave D FF circuit.
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This circuit is designed to respond to the falling edge, Figure 63 (propagation delays shown).

**Figure 63:** Master-slave D FF waveform.
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The standard circuit symbols for the rising and falling edge triggered D flip flops are shown in Figure 64.

**Figure 64:** D FF symbols.
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Reading: Wakerly, Sections 7.1 and 7.2 (pp531).

ANU Engineering - ENGN3213