1. An apparatus for generating random bits, the apparatus comprising: a plurality of mapping devices, wherein a respective mapping device of the plurality of mapping devices is configured to map a predefined number of input signals with the aid of a combinatorial mapping into a predefined number of output signals, wherein the plurality of mapping devices are concatenated with one another, and at least one combinatorial mapping is configured such that a state change of an input signal of a respective mapping device of the plurality of mapping devices is mapped on average onto more than one output signal of the respective mapping device, and wherein no feedback loop is present such that a state change of at least one feedback output signal of a specific mapping device of the plurality of mapping devices is fed as a state change of at least one input signal to another mapping device of the plurality of mapping devices such that one or a plurality of output signals of the specific mapping device is influenced by the state change of the feedback output signal.