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4017 decade counter clock input isn't working? Answered

I got a new 4017 decade counter. When I wire it up it will turn on Q0 output. Pin 13 is grounded and pin 15 is grounded through a 10k resistor. I am using two AA batteries. When I tap the clock pin with a wire connected to power it wont turn on Q1. If I accidentally short the circuit it will change. If I tap pin 15 with power it will reset. Is the chip broken or am I doing something wrong? Please help!


If you're playing with it, ground the count input with something like a 1K resistor too, otherwise it may be indeterminate.

Try A.'s circuit, and make sure you're using 3V+ to drive it.


6 years ago

Here is your circuit.   .   .   .   A


This is just a guess, but it may be that two AA batteries is not enough supply voltage for this IC.  If I can believe what is written in this table here:
the supply voltage range for the 4000 series CMOS is 3 to 18 volts. Two AA batteries will give you something close to 3V, maybe a little less.

Anyway, I am hoping that powering your IC with a stack of 3 or 4 AA batteries, instead of just 2, will make your problem go away.