hi i am zalakkumar patel i would like to get details on simple touch switch using 555 ic ppt.. my friend avi said simple touch switch using 555 ic ppt will be available here and now my college c.ck.pithawala college and technology surat and i need help on...
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Touch Switch is developed using 555 IC timer operated as a MONOSTABLE vibrator. The stable stage is LOW, so the timer outputs are low after the shutter is released. Basically in this circuit we will have an LED that lights when we touch a timer pin. The LED will be on during the time the trigger is present. Once the trigger is triggered, the LED turns off.
Circuit components
• Supply voltage +4 to +6
• 555 IC
• Resistors of 470Ω, 100KΩ
• Capacitors of 10μF, 100nF (104)
• LED
• Touchscreens
Circuit diagram
The following figure shows the circuit diagram of the touch switch.
The voltage supplied in this circuit should not exceed 6V, thus causing the IC burn. The capacitor between pin6 and pin1 determines the turn-on time of the LED once a trigger is passed. This circuit can be modified to turn it on for 2 minutes for a single trip by replacing the capacitance of 10uF with one of 1000uF. So with the capacitance change one can get many turn on the times and so you can make use of this circuit like a ladder box lamp.