公开(公告)号：JPH0376149A

公开(公告)日：1991-04-02

申请号：JP15561390

申请日：1990-06-15

Applicant: SGS THOMSON MICROELECTRONICS

Inventor： MARUKO MORETSURI ,  FUOOBIO MARUCHIOO ,  BURUUNO KABATSURI

IPC: H01L27/04 ,  G05F1/10 ,  H01L21/822 ,  H01L27/06 ,  H02H3/20 ,  H02H9/04

Abstract: PURPOSE: To obtain an integrated circuit protective device which can be implemented using integration technology by providing a Zener diode voltage limiter having a breakdown voltage preset lower than a maximum level being sustained by a circuit under closed state, and an extinction circuit for controlling the opening of the protected circuit. CONSTITUTION: The protective device is connected with a power supply line 50 for an integrated circuit to be protected and comprises a Zener diode voltage limiter 1, as a whole. The limiter comprises a group of three transistors 2, 3, 4 connected, respectively, with connectors which are connected with the power supply line 50. The transistor 2 has, on one side thereof, a base connected with the power supply line through a series Zener diode 5 having a breakdown voltage lower than a maximum voltage being sustained by an integrated circuit 30 under closed circuit state. A Zener diode 10 having a breakdown voltage lower than a maximum voltage being sustained by the integrated circuit under open circuit state is connected with the input to the integrated circuit 30 in parallel with the voltage limiter 1. An extinction circuit 20 having a preset delay T is preset at the input to the voltage limiter 1.