Question

Is it possible to build the equivalent of a master-slave J-K flip-flop using a single 74x74-type edge-triggered D flip-flop and external combinational logic? If so, show the logic. If not, explain why not.  

Why not just use one D flip flop in this problem? Why invert the clock signal when wiring it to the second D flip flop?

Answer 1

Yes,It is possible to build the equivalent of a master-slave j-k flip-flop using a single 74*74-type edge triggered D flip flop.We have to use inverter for getting logic of D flip- flop from JK flip-flop.

If D=0 then j=0 and k=1,Output will be reset(Q=0 & Q^-=1).

If D=1 then j=1 and k=0,Output is set(Q=1 & Q=0). In this way logic can be generated.

We have to generate two signals.They are master and slave signals.So,two D-flip-flops must be used in the circuit.One D-flip-flop is used for generating master signal and other one is used for generating slave flip-flop.Both should not produce at a time.First master signal will come with positive edge triggering clock and next negative triggering is used for slave logic.

Inverter is used to change positive edge triggered clock of master circuit into negative edge triggered clock for slave circuit.Both signals will be generated at different clock timings for showing difference of master and slave logic.