Fork me on GitHub

Project Notes

#850 CD4024 Counter

Introducing the CD4024 7-stage binary counter with a basic demonstration circuit.

Build

Here’s a quick demo..

clip

Notes

The CD4024 7-Stage Ripple Carry Binary Counter is most commonly used as a frequency divider, such as in Modular Synthesizers.

About the CD4024

The CD4024 is a CMOS 7-stage ripple-carry binary counter that divides an input clock frequency by successive powers of two. Each stage toggles the next, producing outputs corresponding to divide-by-2, divide-by-4, divide-by-8, and so on up to divide-by-128. An asynchronous master reset input clears all stages to zero, allowing the counter to be restarted at any time. Because it is a ripple counter, each stage changes state slightly after the previous one, making it ideal for frequency division but less suitable for applications requiring all outputs to change simultaneously.

Operating over a wide supply voltage range of 3V to 15V, the CD4024 combines the low power consumption and high noise immunity characteristic of the CMOS 4000 series. It is commonly used in frequency dividers, timers, event counters, clock generation, and digital sequencing circuits. Its simplicity, reliability, and ability to generate multiple divided clock signals from a single input have made it a popular building block in both hobbyist and industrial digital designs.

cd4024-ref

Circuit Design

The following circuit is a simple demonstration of the CD4024:

  • a 555 timer provides a clock pulse
  • LEDs are attached to display the state of the output pins
  • a push-button pulls the RESET pin momentarily high to reset the counter

Designed with Fritzing: see Counter.fzz.

bb

schematic

Setup on a breadboard. For demonstration purposes I have attached LEAP#791 555 Breadboard Pulse Generator to provide the clock signal.

bb_build

Measuring the Ouput

I’ve attached a logic analyzer to measure the output transitions:

  • D0-D6: attached to Q1-Q7 respectively
  • D7: attached to CLK
  • CH1 (Yellow): attached to Q7 to sync on the slowest changing signal

scope

Circuit with logic analyzer attached:

test1a

Credits and References

About LEAP#850
CMOS/TTL555 TimerCD4024

This page is a web-friendly rendering of my project notes shared in the LEAP GitHub repository.

Project Source on GitHub Return to the LEAP Catalog
About LEAP

LEAP is my personal collection of electronics projects - usually involving an Arduino or other microprocessor in one way or another. Some are full-blown projects, while many are trivial breadboard experiments, intended to learn and explore something interesting.

Projects are often inspired by things found wild on the net, or ideas from the many great electronics podcasts and YouTube channels. Feel free to borrow liberally, and if you spot any issues do let me know or send a pull-request.

NOTE: For a while I included various scale modelling projects here too, but I've now split them off into a new repository: check out LittleModelArt if you are looking for these projects.

Project Gallery view the projects as an image gallery Notebook reference materials and other notes Follow the Blog follow projects and notes as they are published in your favourite feed reader