100 Seconds Duration On Switch with Touch Control by LM555

This is a touch controled switch which keeps the circuit on about 100 seconds after touching the plate connected to the 2 numbered pin. At the end of this time duration, relay releases and the circuit gets to off position.

Automatic Lamp Control with Light Sensitive Switch

The circuit above is an light sensitive automatic switch which functions in absence of light.

One Button On Off Switch with 4093 and IRFZ44

The load is driven by the MOSFET IRFZ44 and 4093 AND gates are used in the circuit. The output of the 4093 IC drives the MOSFET.