Abstract: A method for approximatively determining at least one scalar product of at least one input vector with a weight vector. Input components of the input vector and weight components of the weight vector are present in binary form. At least one matrix circuit is used, wherein the memory cells are programmed according to bits of the weight components. Bits with the same significance of at least a portion of the weight components are respectively programmed in memory cells of the same column. For each of one or more subsets of the input components, a bit sum determination is carried out. To a corresponding subset of the row lines, voltages are applied according to bits with the same significance of the respective subset of the input components and a limited bit sum is determined as the output value of the respective analog-to-digital converter.

Abstract: An arithmetic unit for calculating an approximate value for a product or a sum of two inputted numbers. The arithmetic unit includes arithmetic modules, at least one of the arithmetic modules being provided to calculate individual products or individual sums of digits of the inputted numbers, and the arithmetic modules being connected in an adder that is designed to calculate digits of the product or of the sum from the individual products or from the individual sums. An arithmetic module that is required for the calculation of at least one individual product or individual sum, and/or is required for the propagation of this individual product or this individual sum onto the product or the sum, being absent in the arithmetic unit or being connected there in such a way that it is capable of being selectively deactivated, completely or partially, for the running time of the arithmetic unit.