DinizApp/Electronics Center

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  The DIAC is a full-wave or bi-directional semiconductor switch that can be turned on in both forward and reverse polarities. DIode Alternating Current (DIAC) is widely used to assist even triggering of a TRIAC (or a thyristor). DIAC is composed by three layers (PNP), very much similar to a transistor, however, the doping concentrations in N –type crystal are different. A pair of diodes of four layers in parallel is an equivalent circuit of a DIAC. Typically the DIAC is placed in series with the gate of a TRIAC. DIACs are often used in conjunction with TRIACs because these devices do not fire symmetrically as a result of slight differences between the two halves of the device.

  The DIAC is a full-wave or bi-directional semiconductor switch that can be turned on in both forward and reverse polarities. DIode Alternating Current (DIAC) is widely used to assist even triggering of a TRIAC (or a thyristor). DIAC is composed by three layers (PNP), very much similar to a transistor, however, the doping concentrations in N –type crystal are different. A pair of diodes of four layers in parallel is an equivalent circuit of a DIAC. Typically the DIAC is placed in series with the gate of a TRIAC. DIACs are often used in conjunction with TRIACs because these devices do not fire symmetrically as a result of slight differences between the two halves of the device.

  Um diac é um comutador de onda completa ou bidireccional que dispara nos dois sentidos e ambas as polaridades. Diac significa (diode AC switch – diodo comutador AC). O diac é usado normalmente para activar um Triac ou um Tiristor. É composto por três camadas (PNP), a sua construção assemelha-se a de um transístor bipolar, porém difere na dopagem do cristal N. O circuito equivalente de um diac é um par de díodos de quatro camadas em paralelo. O diac é colocado tipicamente em série com a porta (GATE) de um TRIAC. Os Diacs são usados frequentemente em conjunto com TRIAC porque estes dispositivos não disparam simetricamente em consequência das ligeiras diferenças entre as duas partes do dispositivo.

Historique