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4017 decade counter weird problem // reset not working

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amando96

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hi, just got my self a 4017 decade counter from the shop, wired it up with a 555 timer, works perfectly with 10 LEds, though when i connect the reset to pin 1 only led nº1 and led nº5 are on(and not flashing)this is important because i don't want to flash LEDs with it, i want to drive a stepper motor...

why is this happening?
this is the schematic:
**broken link removed**

though i disconnected the reset from GND, and connected it to pin 1.
am i missing something?

thanks :)
 
The supply bypass capacitor is only 0.01uf. Add a 10uf to 100uF capacitor to hold the supply voltage up when the 555 shorts it with its 400mA current spike.
Or use a low current Cmos 555.
 
Same thing happens, only sequences the first 3 LEDs, i added a 100µF per device, so a 100µF near the 555, and a 100µF near the 4017, could it be damaged or something?

EDIT:

here's what happens, reset to ground, all leds sequence(10leds), reset on Q3, 2 leds sequence, reset on Q4, 3 leds sequence, if i put the reset, on anything over Q4, all leds sequence(10leds)
 
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Amando, are you connecting the Pin 15 directly to the Output (leds anodes)? or to that 1K resistor (leds cathodes)?
 
Directly to the output.

But it works now!
After breakfast i went to try it again, and it worked, maybe there was something on the breadboard short circuiting...

anyway thanks guys :)
 
Breadboards are always full of intermittent connections. Solder the darn circuit on a pcb or on stripboard to make it work properly.
 
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