Thin film magnetic memory device realizing both high-speed data reading operation and stable operation

摘要

Two complementary bit lines corresponding to a selected column are pulled down to a ground voltage via each of a selected MTJ memory cell and a dummy memory cell and are pulled up to a power supply voltage via a read drive selection gate. A read gate corresponding to the selected column drives the voltages of two complementary read data buses by driving force according to the voltage of corresponding complementary two bit lines, respectively. A data reading circuit executes data reading operation on the basis of a voltage difference between the complementary two read data buses. The power supply voltage is determined in consideration of reliability of a tunneling insulating film of an MTJ memory cell.