Patent ID: 6633088
Filing Date: 2003-10-14
Classification: B60R

Abstract:
A drive circuit for an AC ignition circuit including at least one capacitor and at least one trigger element for deploying a restraint system in a motor vehicle, comprising:a bridge circuit including four electronically controllable switches, a first two switches of the four electronically controllable switches being connected in series between a supply voltage and ground, a second two switches of the four electronically controllable switches being connected in series between the supply voltage and ground, and the AC ignition circuit forming a bridge shunt between the first two switches and the second two switches connected in parallel, wherein: the four electronically controllable switches are triggered to guarantee a charge and a discharge of the at least one capacitor in spite of a fault if the fault occurs in the bridge circuit, if a defect occurs in one of two switches connected to ground, the at least one capacitor is charged by: closing two other switches of the four electronically controllable switches, the two other switches being connected to the supply voltage and being connected in series with the one of the two switches connected to ground in which the defect occurs, and closing the two switches connected to ground, and the at least one capacitor is discharged by closing both of the two other switches connected to the supply voltage.