Patent application number | Description | Published |
20090135663 | Memory device and method of operating such a memory device - A memory device and method of operation are provided. The memory device comprises a plurality of memory cells arranged in at least one column, during a write operation a data value being written to an addressed memory cell within a selected column from said at least one column. A supply voltage line is associated with each column, the supply voltage line being connectable to a first voltage source to provide a supply voltage at a first voltage level to the associated column. Threshold circuitry is connected to a second voltage source having a second voltage level, the threshold circuitry having a threshold voltage. Control circuitry is used during the write operation to disconnect the supply voltage line for the selected column from the first voltage source, and to connect the threshold circuitry to the supply voltage line for the selected column. As a result, the supply voltage to the addressed memory cell transitions to an intermediate voltage level determined by the threshold voltage of the threshold circuitry, thereby de-stabilising the addressed memory cell and assisting in the write operation. The technique of the present invention provides a particularly simple and power efficient technique for implementing a write assist mechanism. | 05-28-2009 |
20100177544 | Generating ROM bit cell arrays - A method of generating a ROM bit cell array layout is provided, the method comprising the steps of: inputting a predetermined memory architecture having a predetermined positioning of bit lines and virtual ground lines, said memory architecture comprising a plurality of columns of memory cells, each column of memory cells being located between its own associated bit line and its own associated virtual ground line, and adjacent memory cells in each column of memory cells sharing a common connection to either said associated bit line or said associated virtual ground line; evaluating a possible range of width of active area of each of said columns of memory cells, in dependence on said predetermined positioning of bit lines and virtual ground lines; selecting a final width of active area in dependence on at least one performance characteristic associated with said final width of active area; and generating said ROM bit cell array layout according to said final width of active area. Thus the system designer can reuse an existing memory architecture, yet still retain an advantageous degree of flexibility with regard to performance characteristic selection of the final ROM bit cell array. | 07-15-2010 |
20110249481 | Generating ROM bit cell arrays - A method of generating a ROM bit cell array layout is provided, the method comprising the steps of: inputting a predetermined memory architecture having a predetermined positioning of bit lines and virtual ground lines, said memory architecture comprising a plurality of columns of memory cells, each column of memory cells being located between its own associated bit line and its own associated virtual ground line, and adjacent memory cells in each column of memory cells sharing a common connection to either said associated bit line or said associated virtual ground line; evaluating a possible range of width of active area of each of said columns of memory cells, in dependence on said predetermined positioning of bit lines and virtual ground lines; selecting a final width of active area in dependence on at least one performance characteristic associated with said final width of active area; and generating said ROM bit cell array layout according to said final width of active area. Thus the system designer can reuse an existing memory architecture, yet still retain an advantageous degree of flexibility with regard to performance characteristic selection of the final ROM bit cell array. | 10-13-2011 |
20130308407 | CONTROLLING A VOLTAGE LEVEL OF AN ACCESS SIGNAL TO REDUCE ACCESS DISTURBS IN SEMICONDUCTOR MEMORIES - A semiconductor memory storage device having a plurality of storage cells for storing data, each storage cell comprising an access control device and access control circuitry. The access control circuitry is configured to respond to a data access request signal to access a selected storage cell connected to a corresponding selected access control line to: control the voltage control switching circuitry to connect the at least one capacitor to the voltage supply line such that the at least one capacitor is charged by the voltage supply line and a voltage level on the voltage supply line is reduced; and to control the access control line switching circuitry to connect the selected access control line to the voltage supply line having the reduced voltage level. | 11-21-2013 |