This doesn't have to be 555 as any other solution will be gratefully accepted.
The set-up is a microswitch with NO & NC terminals, a 10 to 20 second delay circuit and a 12v relay. I need a circuit that will operate the relay just ONCE for about 10 seconds when the microswitch is toggled. For example a security light which operates for 10 seconds when a door is opened but just once regardless of the door remaining open or being closed or opened again later.
Ideally I wanted a design in which no current would flow until the switch was operated but being unable to solve this I tried a fall-back solution.
Design 2 comprised a 555 circuit being powered continuously but only sending a single pulse when the switch is opened; however, as the trigger has to be shorted than the output pulse, it remains on if the switch remains open.
Any solutions?
The set-up is a microswitch with NO & NC terminals, a 10 to 20 second delay circuit and a 12v relay. I need a circuit that will operate the relay just ONCE for about 10 seconds when the microswitch is toggled. For example a security light which operates for 10 seconds when a door is opened but just once regardless of the door remaining open or being closed or opened again later.
Ideally I wanted a design in which no current would flow until the switch was operated but being unable to solve this I tried a fall-back solution.
Design 2 comprised a 555 circuit being powered continuously but only sending a single pulse when the switch is opened; however, as the trigger has to be shorted than the output pulse, it remains on if the switch remains open.
Any solutions?