The invention relates to an electric circuit configuration for switching an electrical load, in particular a solenoid valve, by means of a switching means associated with the load, in particular a transistor, wherein the circuit configuration has at least one analysis circuit. The analysis circuit comprises at least one measuring resistor connected in series with the switching means, at least one first analysis means for determining a parameter corresponding to the short-circuit current, and at least one second analysis means for determining a parameter corresponding to the load current.
Electric circuit configurations for switching an electrical load by means of a switching means associated with the load, in particular a transistor, and for detecting a short-circuit are known. The detection of the short circuit serves to open the switching means in the case of a short circuit, for example of the load, in order to prevent damage to the switching means due to too large a current. For this purpose, it is usual to determine a voltage drop across the switching means and to ascertain the short circuit based on this voltage drop. Particularly when a transistor is used as the switching means, the resistance which the transistor in itself forms in the closed state depends on its temperature. There is therefore no immediate relationship between the voltage drop across the switching means and a current which is described as a short-circuit current which flows in the event of a short circuit. On the other hand, it is also usual for the current which flows through the electrical load to be determined by means of an analysis circuit. The short circuit can also be detected based on the current determined in this way. Such an analysis circuit is designed for continuously determining a parameter corresponding to the current flowing through the load. The determination of whether a short circuit is present based on this parameter takes place in an evaluation device downstream of the analysis circuit. As a rule, such a circuit configuration with a multi-stage analysis circuit is too slow for detecting the short circuit and is therefore unable to open the switching means before it becomes damaged due to the short circuit.