An MOS dynamic random access memory (RAM) includes an array of memory cells arranged in rows and columns. The array is divided into two or more sub-arrays. During an operating cycle latching of the sense amplifiers in the sub-arrays is staggered to avoid coincidence of current peaks each arising when the sense amplifiers in one of the sub-arrays are simultaneously latched. Latching takes place first in a sub-array in which a cell is selected. Recovery of the column conductors in the sub-arrays is also staggered to avoid coincidence of current peaks each occurring when one of the sub-arrays is recovered. The sub-array in which a cell is selected is recovered last.