Analog computing unit for representing negative weights

An analog computing unit for an artificial neural network comprising

• an array of non-volatile memory cells, the cells being arranged with rows and columns,
• wherein the columns are arranged such that first columns composed of minus cells for storing negative weights and second columns composed of plus cells for storing positive weights are alternately arranged,
• row lines and bit lines extending in a row direction are alternately arranged in a column direction, and in the cells arranged in the row direction, sources and drains are alternately arranged along the row lines or the bit lines,
• the cells arranged in the same column are connected along the word line,
• in a cell read mode, the cells arranged along the rows are turned on or off alternately one by one and the cells arranged along the columns are turned on or off alternately two by two, and
• currents flowing from the plus cells and the minus cells arranged along the rows are canceled as much as corresponding values, and then only resulting currents are transferred to the bit lines.