Semiconductor device whose operation frequency and power supply voltage are dynamically controlled according to load

摘要

A semiconductor device whose operation frequency and power supply voltage are dynamically controlled according to a load subjected to a process to be performed is disclosed. The semiconductor device includes a memory cell array having SRAM cells arranged in an array form, word lines connected to the SRAM cells for respective rows, a row decoder which selects the word lines one by one during normal operation and multi-select word lines which are not adjacent to each other during low-voltage operation, a load circuit which sets the level of the selected word line to potential lower than power supply voltage, and a controller which controls the row decoder and load circuit to selectively control selection of the word lines and the load circuit.