Patent ID: 8593773

Claim:
A circuit arrangement with two semiconductor switches connected in series between a first potential connection and a second potential connection, wherein an inductive element is connected in series between the two potential connections and by elements of an action chain such that, under predefined conditions, a voltage drop across the inductive element effects the switching off of at least one of the semiconductor switches, wherein the action chain incorporates a Zener diode, wherein a series circuit comprising the Zener diode and a resistive element is provided in a circuit in parallel with the inductive element, and that two terminals of a first auxiliary transistor are coupled to two connections on the resistive element in such a way that a voltage drop across the resistive element determines that the first auxiliary transistor is switched through, wherein the action chain incorporates a timing element; and wherein one of the two terminals of the first auxiliary transistor is coupled to a potential connection and another terminal of the first auxiliary transistor is coupled via a capacitive element to a further potential connection, so that when a voltage is applied across these potential connections and the first auxiliary transistor is switched through, a current flows through the latter and charges up the capacitive element, and where the capacitive element is coupled by two of its connections to two terminals of a second auxiliary transistor, so that a voltage drop across the capacitive element determines through switching by the second auxiliary transistor.