Tiristores

In the transistors section we did the exeperimento of placing two conflicting diodes if, in a way that it will remain equivalent with close glazing NPN or PNP. We realize several tests and we saw his virtues and the way of behaving to the electric current.
We are going to see that it happens if we join two transistors of different polarity, but joining his glazing of equal constitution between themselves of the way that we see in the image. We have left like a transistor to which one more crystal of equal polarity has been added to that of the base. But also we might interpret this element as two diodes, placed one next of other; nevertheless, the presence of a base connection in the crystal P would give a few very particular qualities to this new union of material semiconductors. We are going to call plate (A) to the place that corresponds at the entry of the current; cathode (K) to the place of exit and electrode of government or door (G) at the entry of this base current that provides special characteristics to our new element.
From the electronic point of view we see that this element endures like a diode rectifier but with special conditions. For example, if we apply a small plate tension to him to cathode, the current does not circulate not even as normally a diode would do it; if we invest the polarity it is blocked also and the current does not happen. But if we increase the tension for way, for example, of a variable resistance potenciométrica, on having reached a certain tension, this element becomes a driver in his step sense, and turns into not driver again if the low tension of certain and very precise limits. This characteristic does that it could be interpreted as a switch that gets connected to if the same when the tension applied in sense of step reaches certain value. This characteristic is going to be very important and is going to give to this element a lot of possibilities of use in electronics.
To this type of union, controlled silicon rectifier names him by diode, and it appears sometimes in the schemes with the letters SCR (silicon controlled rectifier), but it turns out to be more current to name him tiristor.

He keeps on reading on Tiristores:

Functioning of the Tiristor.
Curves typical of the Tiristor.
Variety of Tiristores.
Code of designation of diodes controlled semiconductors (Tiristores).