Nonvolatile BIOS memory

Abstract: A flash memory system having a controller and a flash memory device for providing BIOS, operating system and user storage capabilities is provided. According to exemplary embodiments of the present invention, flash memory systems can be designed as integrated circuit packages which are pin compatible with conventional ROM BIOS chips so that existing systems can be readily upgraded without extensive modifications.

Abstract: A nonvolatile SRAM array has an array of integrated nonvolatile SRAM circuits arranged in rows and columns on a substrate. Each of the integrated nonvolatile SRAM circuits includes an SRAM cell, a first and second nonvolatile memory element. The SRAM cell has a latched memory element in communication first and second nonvolatile memory elements to receive and permanently retain the digital signal from the latched memory element. A power detection circuit detects a power interruption and a power initiation and communicates the detection of the power interruption and power initiation to the plurality of integrated nonvolatile SRAM circuits. The SRAM cell, upon detection of the power interruption, transmits the digital signal to the first and second nonvolatile memory elements. The SRAM cell of each of the nonvolatile static random access memories upon detection of the power initiation receives the digital signal from the first and second nonvolatile memory elements.

Abstract: A method of performing multiple writes before an erase to a nonvolatile memory cell is described. A first bit is stored at a first level of a nonvolatile memory cell (110, 120, 130 and 140). A second bit is stored at a second level of nonvolatile memory cell (110, 120, 130 and 140). A method of erasing a nonvolatile memory cell is also described. A level indicator that indicates the next level of the nonvolatile memory cell to write to is incremented. A method of reading a nonvolatile memory cell includes recalling a level indicator. The nonvolatile cell is then sensed at a level indicated by the level indicator to determine the state of the memory cell.

Abstract: In this paper, a new approach toward the design of a memristor based nonvolatile static random-access memory (SRAM) cell using a combination of memristor and metal-oxide semiconductor devices is proposed. Memristor and MOSFETs of the Taiwan Semiconductor Manufacturing Company's 180-nm technology are used to form a single cell. The predicted area of this cell is significantly less and the average read-write power is ~25 times less than a conventional 6-T SRAM cell of the same complementary metal-oxide semiconductor technology. Read time is much less than the 6-T SRAM cell. However, write time is a bit higher, and can be improved by increasing the mobility of the memristor. The nonvolatile characteristic of the cell makes it attractive for nonvolatile random access memory design.