SELECTIVE PRECHARGE METHOD REDUCING POWER CONSUMPTION AND READ-ONLY MEMORY(ROM) DEVICE USING THE SAME

摘要

PURPOSE: A selective precharge method reducing a power consumption and a read-only memory(ROM) device using the same are provided, which reduces a whole power consumption ultimately, by reducing a power consumption in a precharge circuit, by controlling each precharge circuit selectively. CONSTITUTION: A memory cell array(20) are divided into a number of memory blocks, and includes a number of word lines and a number of virtual ground lines and a number of bit lines. A bit line selection part(240-24k) selects one bit line among the above bit lines. A virtual ground line selection part selects one virtual ground line among the above virtual ground lines. Precharge circuits(260-26k) precharge the above bit lines and the above virtual ground lines to a fixed precharge voltage level. A discharge circuit discharges the virtual ground lines to a fixed virtual ground voltage level in response to an output signal of the virtual ground line selection part. The precharge circuit is comprised in each memory block.