A counter is a sequential circuit that goes through a predetermined sequence of states upon the application of clock pulses . Counters can be used to Increment Binary Numbers. (count++) Background (Counters) Types of Counter Synchronous Counter Ripple Counter Common Clock Pulse for all Flip Flops Output of each Flip Flop triggers other Flip Flops
Binary Counter Binary Up-Down Counter BCD Counter Binary Counter with Parallel Load m any more.. List of Synchronous Counters
Truth Table of JK Flip Flop Understanding Circuit Diagram Understanding Logic States Output Truth Table Timing Diagram 4-bit Synchronous Binary Counter
Truth Table of JK Flip Flop J K Q MEANING Q NO CHANGE 1 RESET 1 1 SET 1 1 Q’ TOGGLE
Understanding Circuit Diagram We are using four JK Flip-Flops to built 4-bit synchronous binary counter
Understanding Circuit Diagram As this is a synchronous counter all flip-flops have common clock pulse
Understanding Circuit Diagram We just rearranged the clock inputs so that we don’t get confused
Understanding Circuit Diagram We will be using four AND gates as per textbook, however we can implement this by using just two AND gates also.
Understanding Circuit Diagram Then we connect outputs of all flip-flops to one of the input of individual AND Gates
Understanding Circuit Diagram As we are going to use same input for J and K we will short both of them in each flip flop.
Understanding Circuit Diagram And then we connect inputs of JK-flip flops to the remaining AND input
Understanding Circuit Diagram Outputs of each and gate becomes input to next flip-flop
Understanding Circuit Diagram Then we can connect outputs of each flip-flop and call them A1,A2,A3,A4
Understanding Logic States Initially we assume that the previous stage output is 0. The clock is in off condition
Understanding Logic States Now the clock is in ON condition Here only inputs are given. The negative edge-trigger is applied in the 2 nd instance.
Understanding Logic States Here only inputs are given. The negative edge-trigger is applied in the 3 rd instance.
Understanding Logic States Here only inputs are given. The negative edge-trigger is applied in the 4 th instance.
Understanding Logic States Here only inputs are given. The negative edge-trigger is applied in the 5 th instance.
Clock/Time A 4 A 3 A 2 A 1 1 2 1 3 1 4 1 1 5 1 6 1 1 7 1 1 8 1 1 1 Output at every clock pulse / Truth Table Clock/Time A 4 A 3 A 2 A 1 9 1 10 1 1 11 1 1 12 1 1 1 13 1 1 14 1 1 1 15 1 1 1 16 1 1 1 1