Thin film magnetic memory device having an access element shared by a plurality of memory cells

The thin film magnetic memory device comprising:

• a plurality of memory cells arranged in rows and columns, and divided along in a row direction into a plurality of row blocks;
• each of said memory cells including a tunneling magneto-resistance element having an electric resistance variable depending on magnetically written storage data;
• a plurality of first signal lines arranged in a column direction, and corresponding to the memory cell columns, respectively;
• and
• a plurality of second signal lines arranged corresponding to said plurality of row blocks in each of said memory cell columns, respectively, wherein
• said tunneling magneto-resistance element is electrically coupled between corresponding one of said plurality of first signal lines and corresponding one of said plurality of second signal lines,
• the thin file magnetic memory device further comprising:
• a plurality of word lines arranged in the row direction, corresponding to said plurality of row bocks, respectively, and being selectively activated in accordance with results of row selection in a data read operation;
• and
• a plurality of access transistors arranged corresponding to said plurality of second signal lines, respectively, wherein
• each of said access transistors is electrically coupled between corresponding one of said plurality of second signal lines and a fixed voltage, and is turned on when corresponding one of said word lines is activated.

A thin film magnetic memory device comprising:

• a plurality of memory cells arranged in rows and columns, and divided along in a row direction into a plurality of row blocks;
• each of said memory cells including a tunneling magneto-resistance element having an electric resistance variable depending on magnetically written storage data;
• a plurality of first signal lines arranged in a column direction, and corresponding to the memory cell columns, respectively;
• and
• a plurality of second signal lines arranged corresponding to said plurality of row blocks in each of said memory cell columns, respectively, wherein
• said tunneling magneto-resistance element is electrically coupled between corresponding one of said plurality of first signal lines and corresponding one of said plurality of second signal lines;
• each of said row blocks has the memory cell rows of L (L:
• integer larger than one) in number;
• the second signal line corresponding to the selected memory cell being selected as an access target is coupled to a first voltage over at least one predetermined period provided during a single data read operation;
• said thin film magnetic memory device further comprising:
• a data line to be electrically coupled to the first signal line corresponding to said selected memory cell during each of said at least one predetermined period,
• a read current supply circuit for coupling said data line to a second voltage during each of said at least one predetermined period, and
• a data read circuit for producing read data corresponding to the storage data of said selected memory cell;
• and
• said data read circuit has:
• a first voltage holding portion for holding, on a first internal node, the voltage carried on said data line over the predetermined period provided corresponding to a first state keeping said selected memory cell to have a magnetization direction substantially the same as that before said single data read operation, and
• a voltage comparing portion for producing said read data in accordance with a difference between the voltage on said first internal node and the voltage carried on said data line over the predetermined period provided corresponding to a second state changing the magnetization direction of said selected memory cell from that in said first state by application of a predetermined magnetic field.