| Patent application number | Description | Published |
| 20100214811 | CODING TECHNIQUES FOR IMPROVING THE SENSE MARGIN IN CONTENT ADDRESSABLE MEMORIES - A content addressable memory using encoded data words and search words, and techniques for operating such device. In one embodiment, the data word is transformed into a code word guaranteeing a mismatch of at least two code word bits of different binary values during the memory search operation when the data word does not match a search word. In another embodiment, the search word is transformed into a search code such that the Hamming distance between the code word and the search code is greater than a given threshold when there is a mismatch of at least one bit between the data word and the search word. | 08-26-2010 |
| 20100214829 | MEMORY PROGRAMMING - Systems, methods, and devices for iteratively writing contents to memory locations are provided. A statistical model is used to determine a sequence of pulses to write desired contents to a memory location. The contents can be expressed as a resistance value in a range to store one or more bits in a memory cell. For phase change memory, an adaptive reset pulse and one or more annealing pulses are selected based on a desired resistance range. Reading the resistance value of the memory cell can provide feedback to determine adjustments in an overall pulse application strategy. The statistical model and a look up table can be used to select and modify pulses. Adaptively updating the statistical model and look up table may reduce the number of looping iterations to shift the resistance value of the memory cell into the desired resistance range. | 08-26-2010 |
| 20100214830 | MEMORY READING METHOD FOR RESISTANCE DRIFT MITIGATION - Techniques for reading phase change memory that mitigate resistance drift. One contemplated method includes apply a plurality of electrical input signals to the memory cell. The method includes measuring a plurality of electrical output signals from the memory cell resulting from the plurality of electrical input signals. The method includes calculating an invariant component of the plurality of electrical output signals dependent on the configuration of amorphous material in the memory cell. The method also includes determining a memory state of the memory cell based on the invariant component. In one embodiment of the invention, the method further includes mapping the plurality of electrical output signals to a measurements region of a plurality of measurements regions. The measurements regions correspond to memory states of the memory cell. | 08-26-2010 |
| 20100218071 | WRITING A SPECIAL SYMBOL TO A MEMORY TO INDICATE THE ABSENCE OF A DATA SIGNAL - A method for writing in a memory system that includes receiving an address corresponding to a memory location in a memory, receiving a desired content to be written, encoding the desired content into a symbol, and writing the symbol to the memory location using an iterative write process of at least one write and one read to the memory location. The iterative write process includes determining if the symbol was successfully written to the memory location and exiting the iterative write process in response to the symbol being successfully written to the memory location. The iterative write process also includes determining if a halt condition has been met and exiting the iterative write process if the halt condition has been met. Once the iterative write process has been exited, the memory location may be identified as a candidate for being written with a special symbol. | 08-26-2010 |
| 20110096594 | MEMORY READING METHOD FOR RESISTANCE DRIFT MITIGATION - Techniques for reading phase change memory that mitigate resistance drift. One contemplated method includes apply a plurality of electrical input signals to the memory cell. The method includes measuring a plurality of electrical output signals from the memory cell resulting from the plurality of electrical input signals. The method includes calculating an invariant component of the plurality of electrical output signals dependent on the configuration of amorphous material in the memory cell. The method also includes determining a memory state of the memory cell based on the invariant component. In one embodiment of the invention, the method further includes mapping the plurality of electrical output signals to a measurements region of a plurality of measurements regions. The measurements regions correspond to memory states of the memory cell. | 04-28-2011 |
| 20110228600 | MEMORY PROGRAMMING - Systems, methods, and devices for iteratively writing contents to memory locations are provided. A statistical model is used to determine a sequence of pulses to write desired contents to a memory location. The contents can be expressed as a resistance value in a range to store one or more bits in a memory cell. For phase change memory, an adaptive reset pulse and one or more annealing pulses are selected based on a desired resistance range. Reading the resistance value of the memory cell can provide feedback to determine adjustments in an overall pulse application strategy. The statistical model and a look up table can be used to select and modify pulses. Adaptively updating the statistical model and look up table may reduce the number of looping iterations to shift the resistance value of the memory cell into the desired resistance range. | 09-22-2011 |
| 20110246703 | CONSTRAINED CODING TO REDUCE FLOATING GATE COUPLING IN NON-VOLATILE MEMORIES - Constrained coding to reduce floating gate coupling in non-volatile memories including a method for storing data. The method includes receiving write data to be written to a flash memory device, selecting a codeword in response to the write data, and writing the codeword to the flash memory device. The codeword is selected to reduce floating gate coupling in the flash memory device by preventing specified symbol patterns from occurring in the codeword. | 10-06-2011 |
| 20110252215 | COMPUTER MEMORY WITH DYNAMIC CELL DENSITY - A computer memory with dynamic cell density including a method that obtains a target size for a first memory region. The first memory region includes first memory units operating at a first density. The first memory units are includes in a memory in a memory system. The memory is operable at the first density and a second density. The method also includes: determining that a current size of the first memory region is not within a threshold of the target size and that the first memory region is smaller than the target size; identifying a second memory unit currently operating at the second density in a second memory region, the second memory unit included in the memory; and dynamically reassigning, during normal system operation, the second memory unit into the first memory region, the second memory unit operating at the first density after being reassigned to the first memory region. | 10-13-2011 |