16-Stage Decade Counter Chain - Using two 4017 Chips

Picture of 16-Stage Decade Counter Chain - Using two 4017 Chips
I found a way to easily make a decade counter that has more outputs than just 10.

Objective and Motive:
I really like how binary counters can link together in chains. For example, if you have two 8-stage binary counters, you can use them together to easily make a 16-stage binary counter.
I always wanted to do that with decade counters. And today I found a way to do this!
Remove these adsRemove these ads by Signing Up

Step 1: Gather the Parts

Picture of Gather the Parts

• lots of jumper wires
• two 4017 decade counters
• one 555 timer
• two 0.1 µF capacitors (#104)
• one 10 µF capacitor
• one 1 nF   capacitor (#102)
• five 10KΩ (or anything between 4.7kΩ and 22kΩ)
• three N-channel mosfets
• one switch
• one or two breadboards
• one 5V power supply

With these in hand, you should be ready to make a 16-stage decade counter!

Step 2: Examine the Schematic

Picture of Examine the Schematic
Take a look at this schematic to see how the components fit together.
You can click on the schematic picture to see a full-size version.
The 16 green wires on the right of the schematic are the 16 outputs.
I suggest you put 16 LEDs on those outputs with 1KΩ resistors in series to monitor the outputs of this device.

If you don't know how to read schematics, I suggest following this tutorial:
Collin's Lab: Schematics

Step 3: Build Your Circuit

Picture of Build Your Circuit
Now that you have looked over the schematic, you are ready to build the circuit.
Assemble the circuit on a breadboard using jumper wires to connect components.
I recommend referring back to the schematic while building your circuit on your breadboard.

If you can pack your LEDs together tightly, it will save you some breadboard space.
In the end, I had to expand to using a second breadboard because my LEDs took up so much space.
I'm getting some LED bar graphs to fix this problem  :)
halamka11 months ago
Great -- now hook it up to a memory chip and computer screen .
gprakash11 year ago
Hai friend nice projects you done, and you have a good knowledge,please do me a favour, that how can we construct a circuit that it should be operated when a push button is pressed so that the relay in the circuit will stay on till the push button again pressed, here we should use only a push button which makes a circuit connected when button pressed, and breaks the circuit when removed, please if you have a circuit please send me a mail to
Teslaling1 year ago
That is a brilliant design! I think that it is a very efficient way to "add" counters together. Since they count independent of each other, I assume that means that you could also count odd numbers too. For example if I needed to count to 13, I could stop one on the 8th output and the other on the 7th output right?
jensenr30 (author)  Teslaling1 year ago
Exactly right!
On counter could count to 7 (stop on eight) and the other could count to 6 (stop on 7) so that the total equals 13.
It seems you understand the concept of this device perfectly! :D
I'm glad I was able to show how my machine works.
pfred21 year ago
This is interesting. I would have thought the carry out pin would have been used to clock the second counter. I often like using a 74154 if I need 16 outputs too. This way is more compact.
jensenr30 (author)  pfred21 year ago
ooh. The 74154 looks really nice. I might have to use this for my drum machine instead...
Thanks for the info!