This circuit is one chip universal timer, it can configur all the main types of the timers:
1- ON Delay
2- OFF Delay
3- Dual Delay
4- One Shot ( Monostable)
This circuit has the following features:
a- All Input has a built in pull down resistor (saving in PCB and components).
b- A chip provided by 3 bits Range Multiplier.
c- Dual o/p
d- Master reset.
It is a very useful circuit; I also attached the PCB design.