4017 varients

Hi - maybe being dumb - I have a 4017 chasing light circuit with a 555 clock signal that works fine with a HEF4017BP counter, but when I swap for a HCF4017BE chip it just lights the first LED - I got a load of the HCF4017BE chips to make these with my scout group, but they dont seem to work like my prototype! Is there any difference in how I should treat them? the HCF4017BE was about half the price of the other...
Thanks for any suggestions!
Alan

 

Last suggestion worked! Changed the chip and found that 2 of 9 ICs were bad.

The circuit was a simple 555 astable circuit to give a clock signal to the 4017 which then cycled forwards and back along a line of 6 LEDs. I skipped the capacitor on pin 5 of the 555 and didn't bother putting reset pin 4 high. I didn't protect any of the LEDs with resistors and didn't smooth the inputs to the 4017 with a capacitor between Vdd pin 16 and gnd on the 4017. It was all squeezed on the smallest breadboard with risks of the diodes from 4017 to the LEDs shorting etc etc Nevertheless, when I swapped a new (good) IC in, it all worked fine. No issue with the letters after HFC4017 BP and BE do the same. Rapid's HCF4017BEY is less than half the price that they have a HEF4017BP - anyone know what the difference is?

To test I laid it all out on a big breadboard with smoothing capacitors and protective resistors etc and found same symptoms and then changed the IC which then made it all work as designed. Stripping back to minimal circuit gave no problems with the good ICs...

Are teh 4017s susceptible to damage? the 555 chip seems to take anything put into any pin and then work fine when its wired correctly afterwards, but the two ICs that didn't work were both ones that the scouts had played with first... Anyway - thanks for suggestions - just needed telling to sit down and check it all out properly...

 

I guess so - I used to tell them to be careful but have not had a prob with things for ages! Maybe the scout hut floor is particularly bad? (my kitchen quarry tiles are where we've done most of the recent stuff in an activity club rather than in a troop night... Are the 4017s very sensitive?

 

With the good chip I get 1.5V on the outs connected and about twice that when disconnected (outputs cycling with the clock signal). With the bad chip it gave 9v on output one and 0 on the rest when disconnected and tripped the voltage limit when I connected the LEDs ... Bad things happened to the chip I guess...
I've attached a pic! Little board on left is the production board and bigger board on left has it spread out a bit more...

 

tried and failed to load picture but then read FAQ - see image a couple of posts down

 

Sorry - I'll delete failed picture uploads and try here.
Photo shows scout breadboard on left and a spread out one when I was testing stuff on the right...

Actually, I guess I could skip all the diodes and just use (coated) wire and avoid all the issues with shorts between the diodes...

 

Yep - all the diodes didn't really help and it works just fine with coated wire instead (why am I using diodes to protect the LEDs?). You can see the finished product here http://http://boreattonscouts.blogspot.co.uk/2013/10/chips.html