Patent classifications
G11C16/22
Semiconductor device with secure access key and associated methods and systems
Memory devices, systems including memory devices, and methods of operating memory devices are described, in which security measures may be implemented to control access to a fuse array (or other secure features) of the memory devices based on a secure access key. In some cases, a customer may define and store a user-defined access key in the fuse array. In other cases, a manufacturer of the memory device may define a manufacturer-defined access key (e.g., an access key based on fuse identification (FID), a secret access key), where a host device coupled with the memory device may obtain the manufacturer-defined access key according to certain protocols. The memory device may compare an access key included in a command directed to the memory device with either the user-defined access key or the manufacturer-defined access key to determine whether to permit or prohibit execution of the command based on the comparison.
Methods and systems for improving access to memory cells
The present disclosure relates to a method for accessing an array of memory cells, including storing a set of user data in a plurality of memory cells, storing, in a portion of the array, additional information representative of a voltage difference between a first threshold voltage and a second threshold voltage of the memory cells programmed to a first logic state, applying to the array a read voltage to activate a first group of memory cells corresponding to a preset number of memory cells, determining that the first group of memory cells has been activated based on applying the read voltage, wherein the read voltage is equal to the first threshold voltage when the first group of memory cells has been activated, and based on the additional data information, applying the voltage difference to the array to activate a second group of memory cells programmed to the first logic state.
Methods and systems for improving access to memory cells
The present disclosure relates to a method for accessing an array of memory cells, including storing a set of user data in a plurality of memory cells, storing, in a portion of the array, additional information representative of a voltage difference between a first threshold voltage and a second threshold voltage of the memory cells programmed to a first logic state, applying to the array a read voltage to activate a first group of memory cells corresponding to a preset number of memory cells, determining that the first group of memory cells has been activated based on applying the read voltage, wherein the read voltage is equal to the first threshold voltage when the first group of memory cells has been activated, and based on the additional data information, applying the voltage difference to the array to activate a second group of memory cells programmed to the first logic state.
METHOD FOR DISCARDING PERSONAL INFORMATION IN NAND FLASH MEMORY
A method for discarding personal information comprises at least one among partial overwriting, SLC programming, and applying an erase pulse. The method for discarding personal information comprises a step for acquiring the program status of personal information-containing data of a memory block to be erased, generating data having a status that is equal to or higher than the program status corresponding to the personal information, and carrying out a partial overwriting operation on the personal information by using the generated data.
NON-VOLATILE MEMORY DEVICE READABLE ONLY A PREDETERMINED NUMBER OF TIMES
In an embodiment a noon-volatile memory device includes a memory plane including at least one memory area including an array of memory cells having two rows and N columns, wherein each memory cell comprises a state transistor having a control gate and a floating gate selectable by a vertical selection transistor buried in a substrate and including a buried selection gate, and wherein each column of memory cells includes a pair of twin memory cells, two selection transistors of the pair of twin memory cells having a common selection gate and a processor configured to store in the memory area information including a succession of N bits so that, with exception of the last bit of the succession, a current bit of the succession is stored in two memory cells located on the same row and on two adjacent columns and a current bit and the following bit are respectively stored in two twin cells.
MEMORY SYSTEM, CONTROL METHOD, AND POWER CONTROL CIRCUIT
A memory system includes: a first nonvolatile memory; a second volatile memory; a controller; a power control circuit configured to perform control such that a first voltage is applied to the first memory, the second memory, and the controller based on first power supplied from an external power supply; and a power storage device configured to supply second power to the power control circuit while the first power from the external power supply is interrupted. While the first power supplied from outside is interrupted, the power control circuit applies a second voltage based on the second power supplied from the power storage device to the first memory, the second memory, and the controller. The power control circuit stops the application of the second voltage to the second memory after the data is read from the second memory and before the data is written into the first memory.
Mixed digital-analog memory devices and circuits for secure storage and computing
A non-volatile memory device includes a plurality of memory cells arranged in a matrix, a plurality of word lines extended in a row direction, and a plurality of bit lines extended in a column direction. Each of the memory cells is coupled to one of the word lines and one of the bit lines. The memory device further includes a word-line control circuit coupled to and configured to control the word lines, a first bit-line control circuit configured to control the bit lines and sense the memory cells in a digital mode, and a second bit-line control circuit configured to bias the bit lines and sense the memory cells in an analog mode. The first bit-line control circuit is coupled to a first end of each of the bit lines. The second bit-line control circuit is coupled to a second end of each of the bit lines.
Memory system, memory device, and control method of memory system for generating information from a threshold voltage
According to one embodiment, a memory system includes: a memory device to store data; and a controller to control an operation for the memory device. The memory device executes a program operation by a first program voltage on memory cells belonging to a first address of the memory device; detect at least one first memory cell among the memory cells by using a first determination level and a second determination level different from the first determination level, the at least one first memory cell having a threshold voltage of a value different from a value between the first determination level and the second determination level; and generate unique information of the memory device, based on a position of the first memory cell in the first address.
NONVOLATILE MEMORY DEVICES HAVING ADAPTIVE WRITE/READ CONTROL TO IMPROVE READ RELIABILITY AND METHODS OF OPERATING THE SAME
A storage device includes a controller configured to control a non-volatile memory device(s) having a plurality of memory blocks therein. The controller includes secure erase control logic configured to: (i) control secure erase operations on the plurality of memory blocks in response to a secure erase request received from a host, and (ii) set flags corresponding to the plurality of memory blocks such that a first flag corresponding to a first memory block, which has undergone at least two of the secure erase operations, has a first value. Adaptive control logic is provided, which is configured to change at least one operating condition associated with a write operation and/or read operation directed at the first memory block, in response to detecting that the first flag has the first value.
MEMORY-CONTROL CIRCUIT AND METHOD FOR CONTROLLING ERASING OPERATION OF FLASH MEMORY
A memory-control circuit for use in an integrated circuit is provided. The memory-control circuit includes a memory controller and a timer circuit. The memory controller performs an erase operation on a target data block of the flash memory according to an erase command from a processor, and generates an erase signal. The timer circuit starts a counting operation in response to the erase signal. In response to an intellectual-property-core circuit generating an interrupt signal, the memory controller and the timer circuit respectively suspend the erase operation and the counting operation. In response to the interrupt signal being cleared, the memory controller and the timer circuit respectively resume the erase operation and the counting operation. In response to the timer circuit having counted up to a predetermined value, the timer circuit outputs a completion signal to the memory controller to indicate that the erase operation is complete.