D Latch and D type Flip Flop Question

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gl0ck
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Homework Statement


Hello,



I am thinking about the operation of the D latches and Flip Flops. I know
the operation of Latch :
When clock is hi:
-Q follows D in simple combinational behaviour
- D/Q path is transperant ( what I think it means what is on D can be seen on Q) ?
At the transition from hi to low
- Q output frozen
-Non - combinational behaviour, Q ignores D intput changes.
Circuit diagram of a D latch with transmission gates and inverters, showing the transparent state G = hi and memory state G = lo, with timing waveforms for D, G and Q below.


Flip Flop :
When clock is low:
- the 'master' is transperant
-slave retained memorized output

At the transition low- hi:
-master stores input,slave transperant
-slave passes master stored value to the output
-'Data in' sampled at the rising clock edge, stored and passed to 'Data out'

Diagram of a master-slave D flip-flop built from two D latches, with Data in, Clock, Q and Data out, beside a positive-edge-triggered D flip-flop symbol, above timing waveforms for D, Clock and Q.





My question is about the graphs under the diagrams. Should I take care only on the rising and folling edges of the clock ? Does it what only matters , I mean the values of D and Q on the rising and folling edges? If so, why the output waveform is like this, I mean it is changing during the hold, setup time ?

Thanks

Homework Equations





The Attempt at a Solution

 
In a D flip flop the output only changes on a rising clock edge.