Patent application number | Description | Published |
20080273384 | Non-volatile multilevel memory cells with data read of reference cells - Embodiments of the present disclosure provide methods, devices, modules, and systems for non-volatile multilevel memory cell data retrieval with data read of reference cells. One method includes programming at least one data cell of a number of data cells coupled to a selected word line to a target data threshold voltage (Vt) level corresponding to a target state; programming at least one reference cell of a number of reference cells coupled to the selected word line to a target reference Vt level, the number of reference cells interleaved with the number of data cells; determining a reference state based on a data read of the at least one reference cell; and changing a state read from the at least one data cell based on a change of the at least one reference cell. | 11-06-2008 |
20080273395 | Expanded programming window for non-volatile multilevel memory cells - Embodiments of the present disclosure provide methods, devices, modules, and systems for utilizing an expanded programming window for non-volatile multilevel memory cells. One method includes associating a different logical state with each of a number of different threshold voltage (Vt) distributions. In various embodiments, at least two Vt distributions include negative Vt levels. The method includes applying a read voltage to a word line of a selected cell while applying a pass voltage to word lines of unselected cells, applying a boost voltage to a source line coupled to the selected cell, applying a voltage greater than the boost voltage to a bit line of the selected cell, and sensing a current variation of the bit line in response to the selected cell changing from a non-conducting state to a conducting state. | 11-06-2008 |
20090021987 | Analog sensing of memory cells in a solid state memory device - A memory device that includes a sample and hold circuit coupled to a bit line. The sample and hold circuit stores a target threshold voltage for a selected memory cell. The memory cell is programmed and then verified with a ramped read voltage. The read voltage that turns on the memory cell is stored in the sample and hold circuit. The target threshold voltage is compared with the read voltage by a comparator circuit. When the read voltage is at least substantially equal to (i.e., is substantially equal to and/or starts to exceed) the target threshold voltage, the comparator circuit generates an inhibit signal. | 01-22-2009 |
20090024904 | Refresh of non-volatile memory cells based on fatigue conditions - In one or more of the disclosed embodiments, memory cells in a memory device are refreshed upon an indication of a fatigue condition. In one such embodiment, controller monitors behavior parameters of the cells and determines if any of the parameters are outside of a normal range set for each one, thus indicating a fatigue condition. If any cell indicates a fatigue condition, the data from the block of cells indicating the fatigue is moved to another block. In one embodiment, an error detection and correction process is performed on the data prior to being written into another memory block. | 01-22-2009 |
20090027960 | Cell deterioration warning apparatus and method - Memory devices and methods adapted to process and generate analog data signals representative of data values of two or more bits of information facilitate increases in data transfer rates relative to devices processing and generating only binary data signals indicative of individual bits. Programming of such memory devices includes programming to a target threshold voltage range representative of the desired bit pattern. Reading such memory devices includes generating an analog data signal indicative of a threshold voltage of a target memory cell. Warning of cell deterioration can be performed using reference cells programmed in accordance with a known pattern such as to approximate deterioration of non-volatile memory cells of the device. | 01-29-2009 |
20090066547 | ANALOG-TO-DIGITAL AND DIGITAL-TO-ANALOG CONVERSION WINDOW ADJUSTMENT BASED ON REFERENCE CELLS IN A MEMORY DEVICE - An analog-to-digital conversion window is defined by reference voltages stored in reference memory cells of a memory device. A first reference voltage is read to define an upper limit of the conversion window and a second reference voltage is read to define a lower limit of the conversion window. An analog voltage representing a digital bit pattern is read from a memory cell and converted to the digital bit pattern by an analog-to-digital conversion process using the conversion window as the limits for the sampling process. This scheme helps in real time tracking of the ADC window with changes in the program window of the memory array. | 03-12-2009 |
20090067251 | REDUCING NOISE IN SEMICONDUCTOR DEVICES - The present disclosure includes methods, devices, modules, and systems for reducing noise in semiconductor devices. One method embodiment includes applying a reset voltage to a control gate of a semiconductor device for a period of time. The method further includes sensing the state of the semiconductor device after applying the reset voltage. | 03-12-2009 |
20090067266 | MEMORY CONTROLLER SELF-CALIBRATION FOR REMOVING SYSTEMIC INFLUENCE - Self-calibration for a memory controller is performed by writing a voltage to a selected cell. Adjacent cells around the selected cell are programmed. After each of the adjacent programming operations, the voltage on the selected cell is read to determine any change in voltage caused by systemic offsets such as, for example, floating gate-to-floating gate coupling. These changes are averaged and stored in a table as an offset for use in adjusting a programming voltage or a read voltage in a particular area of memory represented by the offset. Self calibration method for temperature is determined by writing cells at different temperatures and reading at different temperatures to generate temperature offset tables for the write path and read path. These offset tables are used to adjust for systematic temperature related offsets during programming and during read. | 03-12-2009 |
20090097311 | NON-EQUAL THRESHOLD VOLTAGE RANGES IN MLC NAND - Memory devices adapted to process and generate analog data signals representative of data values of two or more bits of information facilitate increases in data transfer rates relative to devices processing and generating only binary data signals indicative of individual bits. Programming of such memory devices includes programming to a target threshold voltage range representative of the desired bit pattern. Reading such memory devices includes generating an analog data signal indicative of a threshold voltage of a target memory cell. Threshold voltage ranges of the memory cells have a larger range size for ranges that include lower threshold voltages and a smaller range size for ranges that include higher threshold voltages since program disturb is lower at higher threshold voltages. | 04-16-2009 |
20090097318 | Programming sequence in NAND memory - An analog voltage NAND architecture non-volatile memory device and programming process is described that reduce the effects of NAND string resistance in source follower sensing by programming the cells in NAND memory cell strings to maintain the resistance presented by the unselected cells on the source-side of a given selected memory cell of the NAND string during both the verify and read. In particular, in one embodiment of the present invention, the cells in the NAND string are programmed sequentially in order from the cells closest the bit line to the final cell that is closest the source line in the string. This allows the source follower sensing of the verify and later read operations to read the programmed threshold voltage across the same stable source-side resistance | 04-16-2009 |
20090141558 | Sensing memory cells - The present disclosure includes methods, devices, modules, and systems for operating memory cells. One method embodiment includes applying a ramping voltage to a control gate of a memory cell and to an analog-to-digital converter (ADC). The aforementioned embodiment of a method also includes detecting an output of the ADC at least partially in response to when the ramping voltage causes the memory cell to trip sense circuitry. | 06-04-2009 |
20090248952 | DATA CONDITIONING TO IMPROVE FLASH MEMORY RELIABILITY - Methods and apparatus for managing data storage in memory devices utilizing memory arrays of varying density memory cells. Data can be initially stored in lower density memory. Data can be further read, compacted, conditioned and written to higher density memory as background operations. Methods of data conditioning to improve data reliability during storage to higher density memory and methods for managing data across multiple memory arrays are also disclosed. | 10-01-2009 |
20090257288 | APPARATUS AND METHOD FOR INCREASING DATA LINE NOISE TOLERANCE - Circuits and methods for improving noise tolerance in memories are disclosed such as those that include biasing a data line above a normal threshold voltage, either by providing a higher data line charge voltage with a voltage source, or by providing a higher data line charge voltage with a current source. | 10-15-2009 |
20090273975 | NON-VOLATILE MULTILEVEL MEMORY CELLS WITH DATA READ OF REFERENCE CELLS - Embodiments of the present disclosure provide methods, devices, modules, and systems for non-volatile multilevel memory cell data retrieval with data read of reference cells. One method includes programming at least one data cell of a number of data cells coupled to a selected word line to a target data threshold voltage (Vt) level corresponding to a target state; programming at least one reference cell of a number of reference cells coupled to the selected word line to a target reference Vt level, the number of reference cells interleaved with the number of data cells; determining a reference state based on a data read of the at least one reference cell; and changing a state read from the at least one data cell based on a change of the at least one reference cell. | 11-05-2009 |
20090310406 | M+L BIT READ COLUMN ARCHITECTURE FOR M BIT MEMORY CELLS - A memory device and programming and/or reading process is described that programs a row of non-volatile multi-level memory cells (MLC) in a single program operation to minimize disturb within the pages of the row, while verifying each memory cell page of the row separately. In one embodiment of the present invention, the memory device utilizes data latches to program M-bits of data into each cell of the row and then repurposes the data latches during the subsequent page verify operations to read M+L bits from each cell of the selected page at a higher threshold voltage resolution than required. In sensing, the increased threshold voltage resolution/granularity allows interpretations of the actual programmed state of the memory cell and enables more effective use of data encoding and decoding techniques such as convolutional codes where additional granularity of information is used to make soft decisions reducing the overall memory error rate. | 12-17-2009 |
20100110798 | PROGRAM WINDOW ADJUST FOR MEMORY CELL SIGNAL LINE DELAY - A memory device and programming and/or reading process is described that compensates for memory cell signal line propagation delays, such as to increase the overall threshold voltage range and non-volatile memory cell states available. Memory cell signal line propagation delay compensation can be accomplished by characterizing the memory cell signal line propagation delay, such as determining an amount of error due to the delay, and pre-compensating the programmed threshold voltage of the memory cells based on the amount of error induced by the memory cell signal line propagation delay and cell location on the selected memory cell signal line. Alternatively, memory cell signal line propagation delay can be post-compensated for, or the pre-compensation fine tuned, after sensing the threshold voltages of the selected memory cells based on the amount of error induced by the memory cell signal line propagation delay and cell location on the selected memory cell signal line. Other methods, devices, etc., are also disclosed. | 05-06-2010 |
20100122103 | CONFIGURABLE DIGITAL AND ANALOG INPUT/OUTPUT INTERFACE IN A MEMORY DEVICE - Methods and memory devices are disclosed, for example a memory device that has both an analog path and a digital path that both share the same input/output pad. One of the two paths on each pad is selected in response to command signals that indicate the nature of the signal being either transmitted to the device or read from the device. Each digital path includes a latch for latching digital input data. Each analog path includes a sample/hold circuit for storing either analog data being read from or analog data being written to the memory device. | 05-13-2010 |
20100146329 | CELL DETERIORATION WARNING APPARATUS AND METHOD - Memory devices and methods adapted to process and generate analog data signals representative of data values of two or more bits of information facilitate increases in data transfer rates relative to devices processing and generating only binary data signals indicative of individual bits. Programming of such memory devices includes programming to a target threshold voltage range representative of the desired bit pattern. Reading such memory devices includes generating an analog data signal indicative of a threshold voltage of a target memory cell. Warning of cell deterioration can be performed using reference cells programmed in accordance with a known pattern such as to approximate deterioration of non-volatile memory cells of the device. | 06-10-2010 |
20100208524 | SOFT LANDING FOR DESIRED PROGRAM THRESHOLD VOLTAGE - Methods of programming memory cells are disclosed. In at least one embodiment, programming is accomplished by applying a first set of programming pulses to program to an initial threshold voltage, and applying a second set of programming pulses to program to a final threshold voltage. | 08-19-2010 |
20100265771 | METHOD OF PROGRAMMING MEMORY CELLS OF SERIES STRINGS OF MEMORY CELLS - Method of programming memory cells of series strings of memory cells include programming a target memory cell of a series string of memory cells after programming each memory cell of the string located between the target memory cell and a first end of the string, and verifying the programming of the target memory cell by applying a bias at a second end of the string opposite the first end and sensing a voltage developed at the first end in response to the bias. | 10-21-2010 |
20110007566 | MEMORY CONTROLLER SELF-CALIBRATION FOR REMOVING SYSTEMIC INFLUENCE - Self-calibration for a memory controller is performed by writing a voltage to a selected cell. Adjacent cells around the selected cell are programmed. After each of the adjacent programming operations, the voltage on the selected cell is read to determine any change in voltage caused by systemic offsets such as, for example, floating gate-to-floating gate coupling. These changes are averaged and stored in a table as an offset for use in adjusting a programming voltage or a read voltage in a particular area of memory represented by the offset. Self calibration method for temperature is determined by writing cells at different temperatures and reading at different temperatures to generate temperature offset tables for the write path and read path. These offset tables are used to adjust for systematic temperature related offsets during programming and during read. | 01-13-2011 |
20110063906 | MEMORY ADAPTED TO PROGRAM A NUMBER OF BITS TO A MEMORY CELL AND READ A DIFFERENT NUMBER OF BITS FROM THE MEMORY CELL - A memory has a memory array with a memory cell. The memory is adapted to program a first number of bits into the memory cell. The memory is adapted to sense a second number of bits, different from the first number of bits, from the memory cell. | 03-17-2011 |
20110090735 | EXPANDED PROGRAMMING WINDOW FOR NON-VOLATILE MULTILEVEL MEMORY CELLS - Embodiments of the present disclosure provide methods, devices, modules, and systems for utilizing an expanded programming window for non-volatile multilevel memory cells. One method includes associating a different logical state with each of a number of different threshold voltage (Vt) distributions. In various embodiments, at least two Vt distributions include negative Vt levels. The method includes applying a read voltage to a word line of a selected cell while applying a pass voltage to word lines of unselected cells, applying a boost voltage to a source line coupled to the selected cell, applying a voltage greater than the boost voltage to a bit line of the selected cell, and sensing a current variation of the bit line in response to the selected cell changing from a non-conducting state to a conducting state. | 04-21-2011 |
20110110152 | NON-VOLATILE MULTILEVEL MEMORY CELLS WITH DATA READ OF REFERENCE CELLS - Embodiments of the present disclosure provide methods, devices, modules, and systems for non-volatile multilevel memory cell data retrieval with data read of reference cells. One method includes programming at least one data cell of a number of data cells coupled to a selected word line to a target data threshold voltage (Vt) level corresponding to a target state; programming at least one reference cell of a number of reference cells coupled to the selected word line to a target reference Vt level, the number of reference cells interleaved with the number of data cells; determining a reference state based on a data read of the at least one reference cell; and changing a state read from the at least one data cell based on a change of the at least one reference cell. | 05-12-2011 |
20110235422 | APPARATUS HAVING A STRING OF MEMORY CELLS - Apparatus having a string of memory cells are useful in semiconductor memory. Some apparatus have circuitry configured to program memory cells of the string in a particular sequence. Some apparatus have circuitry configured to program a threshold voltage of a selected memory cell in the string to match a target voltage compensating, at least in part, for a voltage drop across any unselected memory cells in the string on a source side of the selected memory cell during a sensing operation. Some apparatus have circuitry configured to maintain a resistance presented by source-side unselected memory cells of the string the same between a program verify operation and a later read operation. | 09-29-2011 |
20110242900 | MEMORY CELL SENSING DEVICES AND METHODS - The present disclosure includes methods, devices, and systems for sensing memory cells. One or more embodiments include providing an output of a first counter to a digital-to-analog converter (DAC). An output of the DAC can correspond to a ramping voltage provided to a control gate of the memory cell. An output of a second counter can be provided to sensing circuitry coupled to a sense line of the memory cell. Conduction of the sense line in response to the ramping voltage can be sensed, and an output value of the second counter can be determined in response to the sensed conduction of the sense line. | 10-06-2011 |
20110249507 | SENSING MEMORY CELLS - The present disclosure includes methods, devices, modules, and systems for operating memory cells. One method embodiment includes applying a ramping voltage to a control gate of a memory cell and to an analog-to-digital converter (ADC). The aforementioned embodiment of a method also includes detecting an output of the ADC at least partially in response to when the ramping voltage causes the memory cell to trip sense circuitry. | 10-13-2011 |
20110273933 | ANALOG-TO-DIGITAL AND DIGITAL-TO-ANALOG CONVERSION WINDOW ADJUSTMENT BASED ON REFERENCE CELLS IN A MEMORY DEVICE - An analog-to-digital conversion window is defined by reference voltages stored in reference memory cells of a memory device. A first reference voltage is read to define an upper limit of the conversion window and a second reference voltage is read to define a lower limit of the conversion window. An analog voltage representing a digital bit pattern is read from a memory cell and converted to the digital bit pattern by an analog-to-digital conversion process using the conversion window as the limits for the sampling process. This scheme helps in real time tracking of the ADC window with changes in the program window of the memory array. | 11-10-2011 |
20110289254 | CONFIGURABLE DIGITAL AND ANALOG INPUT/OUTPUT INTERFACE IN A MEMORY DEVICE - Methods and memory devices are disclosed, for example a memory device that has both an analog path and a digital path that both share the same input/output pad. One of the two paths on each pad is selected in response to command signals that indicate the nature of the signal being either transmitted to the device or read from the device. Each digital path includes a latch for latching digital input data. Each analog path includes a sample/hold circuit for storing either analog data being read from or analog data being written to the memory device. | 11-24-2011 |
20110305090 | MEMORY CONTROLLER SELF-CALIBRATION FOR REMOVING SYSTEMIC INFLUENCE - Self-calibration for a memory controller is performed by writing a voltage to a selected cell. Adjacent cells around the selected cell are programmed. After each of the adjacent programming operations, the voltage on the selected cell is read to determine any change in voltage caused by systemic offsets such as, for example, floating gate-to-floating gate coupling. These changes are averaged and stored in a table as an offset for use in adjusting a programming voltage or a read voltage in a particular area of memory represented by the offset. Self calibration method for temperature is determined by writing cells at different temperatures and reading at different temperatures to generate temperature offset tables for the write path and read path. These offset tables are used to adjust for systematic temperature related offsets during programming and during read. | 12-15-2011 |
20120002468 | CELL DETERIORATION WARNING APPARATUS AND METHOD - Memory devices and methods adapted to process and generate analog data signals representative of data values of two or more bits of information facilitate increases in data transfer rates relative to devices processing and generating only binary data signals indicative of individual bits. Programming of such memory devices includes programming to a target threshold voltage range representative of the desired bit pattern. Reading such memory devices includes generating an analog data signal indicative of a threshold voltage of a target memory cell. Warning of cell deterioration can be performed using reference cells programmed in accordance with a known pattern such as to approximate deterioration of non-volatile memory cells of the device. | 01-05-2012 |
20120008399 | METHODS OF OPERATING MEMORIES INCLUDING CHARACTERIZING MEMORY CELL SIGNAL LINES - Methods of operating memories facilitate compensating for memory cell signal line propagation delays, such as to increase the overall threshold voltage range and non-volatile memory cell states available. Methods include selecting a memory cell signal line of a memory and characterizing the memory cell signal line by determining an RC time constant of the memory cell signal line. | 01-12-2012 |
20120030529 | REFRESH OF NON-VOLATILE MEMORY CELLS BASED ON FATIGUE CONDITIONS - In one or more of the disclosed embodiments, memory cells in a memory device are refreshed upon an indication of a fatigue condition. In one such embodiment, controller monitors behavior parameters of the cells and determines if any of the parameters are outside of a normal range set for each one, thus indicating a fatigue condition. If any cell indicates a fatigue condition, the data from the block of cells indicating the fatigue is moved to another block. In one embodiment, an error detection and correction process is performed on the data prior to being written into another memory block. | 02-02-2012 |
20120275233 | SOFT LANDING FOR DESIRED PROGRAM THRESHOLD VOLTAGE - Methods of programming memory cells are disclosed. In at least one embodiment, programming is accomplished by applying a first set of programming pulses to program to an initial threshold voltage, and applying a second set of programming pulses to program to a final threshold voltage. | 11-01-2012 |
20130007355 | DATA CONDITIONING TO IMPROVE FLASH MEMORY RELIABILITY - Methods and apparatus for managing data storage in memory devices utilizing memory arrays of varying density memory cells. Data can be initially stored in lower density memory. Data can be further read, compacted, conditioned and written to higher density memory as background operations. Methods of data conditioning to improve data reliability during storage to higher density memory and methods for managing data across multiple memory arrays are also disclosed. | 01-03-2013 |
20140298088 | DATA CONDITIONING TO IMPROVE FLASH MEMORY RELIABILITY - Methods for managing data stored in a memory device facilitate managing utilization of memory of different densities. The methods include reading first data from a first number of pages or blocks of memory cells having a first density, performing a data handling operation on the read first data to generate second data, and writing the second data to a second number of pages or blocks of memory cells having a second density, wherein the second density is different than the first density, and wherein the second number is different than the first number. | 10-02-2014 |