LED timer

[rzenc]

Hi there,

So, I was asked to built a kind of toy...a push button which turn on a led for about 10s and then it should come off....well, I did in on the protoboard and it worked...build a prototype and it worked...

I gave it to a friend...it's working fine...

Another friend saw it and wanted one too...instead of making another PCB, I decided to build it on the protoboard again in order to check current flow on components and to my surprise..it doesn't want to work anymore...

It turns on but never comes off....

Schem is attached...I used guidelines from LM555C to make a monostable circuit...the actual chip is NE555N

I have fooled around with different combinations of R & C but no joy yet...either it works for about 1.5s and shuts off or it just never turns off...it's driving me mad...

Links to both datasheet of 555 chips

http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00000479.pdf

http://www.ti.com/lit/ds/symlink/lm555.pdf

Can you guys help me out?? don't know where to look since I have limited experience with SS and chips...

Thanks in advance for all

Best Regards

R.

[sluckey]

Where's your timing cap???

Wire it like this...

[rzenc]

Where's your timing cap???

I may have deleted it accidentaly...

I will try your suggestions

THANKS Steve

Best Regards

R.

[rzenc]

Thanks a lot Steve!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

It's not only working, but also got a plus since the other circuit was lighting the LED's when first turning it on....and now it doesn't until I hit the button!!!

GOD SAVE STEVE!!!!!!!!!!!!!!

Best Regards

R.