Patent ID: 7599159

Claim:
A voltage-resistant switch, said switch comprising: a first switching contact; a second switching contact; a first MOS switching transistor having a source terminal, a drain terminal, and a gate terminal, and wherein the source terminal of the first MOS switching transistor is connected to the second switching contact, and the drain terminal of the first MOS switching transistor is connected to the first switching contact, and wherein the voltage-switch is adapted for switching a potential which is to be applied to or which is applied to the first or the second switching contact; and a switching monitoring unit with a control input and a protection output which is connected to a switching input of a protection switch, and wherein said protection switch electrically connects the gate terminal of the first MOS switching transistor to the source terminal of the first MOS switching transistor in dependence on a protection signal when the switching monitoring unit outputs the protection signal to a protection input of the protection switch, and wherein the switching monitoring unit is adapted to produce and output said protection signal in dependence on a potential at either said gate terminal or said source terminal of said first MOS switching transistor to provide protection against exceeding a breakdown voltage of said first MOS switching transistor, wherein the switching monitoring unit includes a control output connected to the gate terminal of the first MOS switching transistor, and wherein the switching monitoring unit is adapted for acting on the gate terminal of the first MOS switching transistor with a control potential for turning on or for blocking the first MOS switching transistor, between the source terminal and the gate terminal of the first MOS switching transistor, and wherein the switching monitoring unit is adapted to select the control potential from a number of predetermined control potentials in dependence on a predetermined switching potential that is to be switched by said voltage-resistant switch, or a first potential which is applied to or is to be applied to the first switching contact and is to be switched by said voltage-resistant switch and/or a second potential which is applied to or is to be applied to the second switching contact and is to be switched by said voltage-resistant switch, in a predetermined manner.