Exploring a CD4017 decade counter

Thread Starter


Joined Mar 17, 2015
I am a beginner in electronics and purchased an electronic 'dice' kit on ebay.

It randomly lights up one of 7 LED's when you press a button and has a CD4017 decade counter.


I have an oscilloscope (DS1074z) and signal generator and wonder if a simple (inexpensive) logic analyser would help me explore how this IC (an any others) works.

What LA would you suggest? I know some of the cheap Chinese one have really buggy software and even the STUMP-based ones do not work well.

What is a reasonable one for $100-150 usd. I am located in Canada.


Joined Mar 12, 2015
There's really not that much to explore on an decade counter. The schema of it is it takes an clock input and in turn sequences through its outputs 0 to 9 on the falling edge of the clock signal. Only one output can be logic high at any given time. The speed of the output is proportional to the clock input divided by 10. The IC has an reset function so that it could be made to be an divide by say 5 counter, or anything under 10. Multiple ICs can be cascaded together. Not really much else to say about it...


Joined Mar 12, 2015
I like the decade counter 4017 for giving extra power to small microcontrollers. Extra output pins at the compromise of speed and required firmware.




Joined Aug 7, 2008
I think that the 4017 is a fun chip. Must remember that in reset the "0" is high. Count triggers on positive rise of clock. There is a recent poat, " LED dice w slow down " , by allenpitts. At the top of this page, upper right there is a search box, put in, LED dice w slow down .
It will sink ( bring to ground ) more current than source, but but is normally used to source. It will cource more current at higher Vcc as: At 8 V Vcc 7.5 V, LED I = 7.4 mA; @ 15 V, LED I = 24 mA, well beyoud the logic level rating of around 3 mA.