摘要 |
Semiconductor component intended to protect electric circuits against overvoltages and overcurrents, particularly due to lightning. In order to improve the energizing conditions of said component, independently of the wave form of the overvoltage appearing between terminals, there is provided a structure concentric with a Zener diode (zone A) at the center of an auxiliary thyristor (zone B), which is itself at the center of a main thyristor (zone A). In the event of an overvoltage, the Zener diode conducts and establishes a trigger current for the auxiliary thyristor and the main thyristor. The auxiliary thyristor trips before the main thyristor and provides a current with steep rise slope which contributes to the uniform energization of the main thyristor. This principle may be extended to bidirectional structures. |