The thyristor (Thyristor SCR Silicon-Controlled Rectifier)

triac 

The thyristor (SCR Silicon-Controlled Rectifier) ​​is the silicon chip with three ends. With proper polarity and electrical command can becomes  switch  controlled.

If the anode of the thyristor is positive voltage relative to the cathode and the gate "give" small continuous instantaneous current by isolated circuit to the cathode, then the anode will be current to the cathode



Once the nihilist tendency or is negative, the thyristor "cuts" and wait again positive voltage pulse and starting to turn again.
The maximum current operation, which depends on the model and the form is on the order of thousands of amperes.
Reverse withstand voltage before destroyed (the cathode), is also in the thousands of volts.
The temperature developed during operation require the existence sink for heat dissipation.

Typically thyristor (scr). A Rising is the thread.

The descent into large and small projecting portal

metal right

 Name thyristor "came" from the beginning of the name thyratron and the ending of the word transistor. The thyratron was the ancestor of the thyristor as a lamp and did the same job.


The GTO thyristor (Gate Tern Off thyristor) is the thyristors, as the name suggests, can "cut" the power if we give to give the gate reverse current

thyristor

The triac (triac) is flanked by two thyristors in the same "package" so that you can control the flow in both directions. The triac is the element used in the dimmer that control the intensity of the incandescent lamp brightness.