A switching unit serves for the arithmetic linking of at least two input signals supplied to the switching unit. For this purpose, the switching unit provides a switching matrix to which the at least two input signals are supplied. The switching matrix applies at least one summation operation to at least two input signals and/or at least one multiplication operation to at least one input signal. Additionally or alternatively, the switching matrix can also connect at least one input signal directly through to a first output. The switching matrix comprises for this purpose several current switches.