Leistungsschaltkreis für eine Airbagzündpille

摘要

A power switch circuit for driving an airbag squib module comprises a power transistor (110), a pre-charge capacitance (120) for storing a charge, a charging circuit (140) and a controllable energy-coupling element. The power transistor (110) has a first electrode (E1), a second electrode (E2) and a control electrode. A path between the first electrode (E1) and the second electrode (E2) is connected in series with the airbag squib module (120) between a supply potential (V SUP ) and a reference potential (V REF ). The charging circuit (140) charges the pre-charge capacitance (130) and the charging circuit (140) is therefore coupled with the pre-charged capacitance (130). The controllable energy coupling element (134) is connected between a first electrode of the pre-charge capacitance (130) and the control electrode (control) of the power transistor (110). The inventive power switch exhibits a high degree of stability, allows a fast switching of the power transistor (110) and further comprises an advantageous transient response.