The 1st terminal which is formed as the overvoltage protection instrument null 1st field which

摘要

This invention the 1st terminal area which is formed as the 1st territory of 1st electric conduction type includes (1), it regards thyristor structure. The 2nd territory of 2nd electric conduction type (2) touches the 1st territory (1) and boundary. The 3rd territory of 1st electric conduction type (3) is confronted, the 2nd territory (2) the 2nd territory (2) possesses the common surface. The 2nd terminal area which is formed as the 4th territory of 2nd electric conduction type (4) touches the 3rd territory and boundary. The auxiliary electrode (6 and 7) the 2nd territory (2) and the 3rd territory (3) is located to the common surface, the said auxiliary electrode (6 and 7) at least one of the said two territories is confronted. Selective figure Figure 1