SEMICONDUCTOR MEMORY DEVICE, IN WHICH THE STAGE NUMBER OF REPLICA CELLS IS VARIED IN PROGRAMMABLE MANNER

摘要

PURPOSE: A semiconductor memory device is provided to supply an optimum start timing to a sense amplifier circuit without increasing layout area. CONSTITUTION: A memory array(100) includes a number of memory cells(106). A sense amplifier circuit(103) amplifies data read in a bit line from a memory cell selected by the memory array. A replica circuit(104A) has the same device as the memory cell, and includes a number of replica cells outputting a signal of a level according to the stage number to a common replica bit line. A sense amplifier control circuit(105) receives a signal of the replica bit line, and performs to control a timing of the signal starting the sense amplifier circuit. The replica circuit includes a switch(110) switching the stage number of an enabling replica cell.