Thyristors is a device which includes four layers. It includes the class of semiconductor elements. It has wide range of intruments, SCR (silicon controlled rectifier), SCS (silicon controlled switch), Diacs, Triacs, and Shockley diodes. It is utilized in high power switching like hundreds of amps and thousands of watts.

Triac is a five-layer device. The section among MT1 and MT2 are arranged in parallel switches namely PNPN and NPNP. It permits triggering of positive and negative gate. It exists in many shapes and sizes. It is important in every operation. It has various mounting methods.

The applications of Simple Triac Switch are small control current/voltage. It reduces mechanical wear in a relay and available inexpensive. The diodes include two semiconductors such as Silicon (Si)
and Germanium (Ge). The components include four valence electrons. The conduction band is referred like lowest unfilled energy band.

 The valence band is the energy area in which regions are filled with valence electrons. Electrons of valence band are placed in the conduction band by using energy and thermal energy.

 The material is divided into Insulator, Semiconductor, and Conductor. Semiconductors possess two properties. Conductivity enhances with temperature like thermistor. It is incremented and controlled with the addition of impurities known as doping.


The Mechatronics Mechanical 2012 Project Document conclusion made on the Triac which is a three terminal switch with AC semiconductor. It switches on with a less energy signal available in the Gate. MT1 and MT2 are the terminals that possess current. G is the gate terminal utilized for triggering.

Download Mechatronics Mechanical 2012 Project Document.