Abstract: A circuit breaker has a main current path which has a controllable first switching element with a first control input that is connected to a controllable second switching element of a drive circuit. The drive circuit has a current sensor which is coupled to the main current path and which has two outputs. An electrical voltage which is applied between the two outputs is dependent on an electric current conducted by way of the main current path. Each of the outputs is connected to in each case one input of a microcontroller-free characteristic curve circuit with two further outputs, and the second switching element is operated depending on a further electrical voltage which is applied between the further outputs. A functional relationship exists between the further electrical voltage and the electrical voltage.