Introduction: J-K Flip-Flop - How It Works

About: Retired teacher and High School Principal. Teacher of math, science, digital electronics, computer leteracy, computer programing

The J-K Flip-Flop IC is used to shift data from one point to another in a circuit in a timed fashion using a clock/strobe pulse to control the data flow. The J-K is also used as a binary counter. The number of bits in the counter byte is determined by the number of J-Ks that are linked (output-to-input fashion). As a teacher I found the J-K ideal for teaching the concepts of data shifting (control) and binary counting. My students could underatand these concepts easily enough. However, they had great difficulty visualizing the workings of the Flip-Flop action which accomplishes these tasks. I wrote a program that graphically and dynamically depics what happens inside the J-K chip - MODES (master,slave), HI and LO activated, POSITIVE and NEGATIVE logic, STROBE, PULSE, LEADING and TRAILING pulse edges, WAIT state, DISABLED state, SYNCHRONOUS and ASYNCHRONOUS operation.

I expect that not many hackers who frequent Instructable are interested in the topic, but for those who are, enjoy. My students did (I am retired).

When you RUN the JKFF.EXE program, wait a few seconds for the program to load and auto-execute.

Note: Ignore the address information in the title page.


Step 1: J-K Flip-Flop Layout

This is a dual J-K chip with not inner connections between the individual J-Ks.