Thin film magnetic memory device including memory cells having a magnetic tunnel junction

Abstract

In the data read operation, a memory cell and a dummy memory cell are respectively coupled to two bit lines of a selected bit line pair, and a data read current is supplied thereto. In the selected memory cell column, a read gate drives the respective voltages on a read data bus pair, according to the respective voltages on the bit lines. A data read circuit amplifies the voltage difference between the read data buses so as to output read data. The use of the read gate enables the read data buses to be disconnected from a data read current path. As a result, respective voltage changes on the bit lines are rapidly produced, whereby the data read speed can be increased.

1 - 15 . (canceled)  
   
   
       16 . A thin film magnetic memory device comprising: 
 a memory array including a plurality of magnetic memory cells;    a plurality of bit lines for reading out memory cell data stored in said magnetic memory cells;    a sense amplifier for sensing the memory cell data read out on said bit lines; and    a bit line selecting portion provided between said bit lines and said sense amplifier and for selecting a bit line pair, wherein    every two of said bit lines form the bit line pair, and the two bit lines forming the bit line pair are arranged in parallel with each other, and    said bit line selecting portion connects the selected bit line pair to said sense amplifier in a data read.    
   
   
       17 . The thin film magnetic memory device according to  claim 16 , further comprising a dummy cell for generating a reference level for use in said data read, wherein 
 one bit line and the other bit line forming the bit line pair connected to said sense amplifier are further connected to one of said magnetic memory cells and said dummy cell, respectively.    
   
   
       18 . The thin film magnetic memory device according to  claim 16 , further comprising a plurality of data lines for writing data to said magnetic memory cells, wherein 
 said data lines are arranged not to form a data line pair consisting of two data lines parallel and adjacent to each other.    
   
   
       19 . A thin film magnetic memory device comprising: 
 a memory array including a plurality of magnetic memory cells;    a plurality of bit lines for reading out memory cell data stored in said magnetic memory cells; and    a data output circuit for outputting output data in accordance with the memory cell data, said data output circuit including    a sense amplifier for sensing the memory cell data read out on said bit lines, and    a data latch circuit for latching the output of said sense amplifier to generate said output data.    
   
   
       20 . A thin film magnetic memory device further comprising: 
 a memory array including a plurality of magnetic memory cells;    a plurality of data write current lines for writing data to said magnetic memory cells; and    a current driver for selectively connecting one end side of at least one of said data write current lines to a driving voltage; wherein    the other end side of each of said data write current lines is connected to a fixed voltage.    
   
   
       21 . A thin film magnetic memory device further comprising: 
 a memory array including a plurality of magnetic memory cells;    a plurality of data write current lines for writing data to said magnetic memory cells; and    a data write circuit for supplying a data write current to a selected data write current line of said data write current lines that corresponds to a selected memory cell of said magnetic memory cells, wherein    said data write circuit guides at least a part of said data write current on said selected data write current line to at least one of the remaining unselected data write current line of data write current lines, and    a magnetic field generated by said selected data write current line and a magnetic field generated by said unselected data write current line act to cancel each other in a region corresponding to at least one of the magnetic memory cells other than said selected memory cells.    
   
   
       22 . The thin film magnetic memory device according  claim 21 , further comprising a current driver for selectively connecting one end side of at least one of said data write current lines to a driving voltage; wherein 
 the other end side of each of said data write current lines is connected to a fixed voltage.