CD4047 Monostable/ Astable Multivibrator

CD4047B is capable of operating in either the monostable or astable mode. It requires an external capacitor (between pins 1 and 3) and an external resistor (between pins 2 and 3) to determine the output pulse width in the monostable mode, and the output frequency in the astable mode.

CD4047 Monostable/ Astable Multivibrator Datasheet