Design and Construction of Clap Activated Switch

Design and Construction of Clap Activated Switch

  IJETT-book-cover  International Journal of Engineering Trends and Technology (IJETT)          
  
© 2018 by IJETT Journal
Volume-60 Number-1
Year of Publication : 2018
Authors : Tomiwa A. C.
DOI :  10.14445/22315381/IJETT-V60P204

Citation 

Tomiwa A. C. "Design and Construction of Clap Activated Switch", International Journal of Engineering Trends and Technology (IJETT), V60(1),33-40 June 2018. ISSN:2231-5381. www.ijettjournal.org. published by seventh sense research group

Abstract
A sound activated switch is a device that utilizes sound to control appliances. An example of a sound activated switch is the one that works by mere clapping of hand. This could be likened to the stopwatch system used in the international athletics competition which uses a gunshot to trigger it to start. Clap activated switch (CAS) is a simple type of control system that requires a clap to control e.g a lamp. This is able to be achieved because it has a microphone that picks up sound and a high gain amplifier that amplifies the sound to about 120times of its input level. The sound is now sent to one-shot monostable circuit that is configured to be triggered by a clap.The monostable circuit also acts as a Schmitt trigger as it converts the clap sound to a square pulse, sending it as a clock pulse to a D type flip-flop. The flip-flop causes a change in output latching it either ON or OFF. This latching is used to control light bulb, using a relay via a relay driver circuit.

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Keywords
Flip-flop, Monostable, Astable, Relay.