CD4047 mono/astable multivibrator

Hi all,

just purchased the cd4047b ic and cannot get the monostable operation to work.

i'm using a 33uf cap and 100k resistor for timing. pins 4,8,14 are connected to vdd and 5,7,9,12 are ground.

i should be getting 8.125seconds but it remains on forever.

can somebody help me?

thanks

Would you mind post your circuitry?

You need pin 4 connected to ground and pin 5 connected to vdd for astable operation. The bar over the astable label means it's an inverted command and must be low to be active.

4047 info

check the data sheet..

https://www.fairchildsemi.com/ds/CD/CD4047BC.pdf