Logic Circuits & Shift Registers?

Question

Hey all,

Could anyone point me to a logical diagram of, or show me how to create, a Parrallel In/Serial Out shift register that uses J-K Flip flops? I've found diagrams that use D types, but no J-K's. Any help would be greatly appreciated.

Thanks.

Answer 1

If you already have a circuit using D-flipflops use it!. a D flipflop is just a jk-flipflop with an inverter before the k-input, and j+k wired together.

E.g take your jk flipflop:

 +-----+
 |j   Q|
 |     |
 |Clk  |
 |     |
 |k  ~Q|
 +-----+

An turn it into a D flipflop:

       +-----+
D------|j   Q|----- Q
   |   |     |
   |   |Clk  |
   |   |     |
   ---O|k  ~Q|
       +-----+

Leave the unused ~Q output floating and you have it.

Note that I haven't drawn the inverter itself, it's the little 'O' sitting at right at the k-input. Don't leave this one out or the D-flipflop will not work.

Good luck.