Abstract:
A system having serially connected memory devices in a ring topology organization to realize high speed performance. The memory devices have dynamically configurable data widths such that the system can operate with up to a maximum common number of active data pads to maximize performance, or to operate with a single active data pad to minimize power consumption. Therefore the system can include a mix of memory devices having different data widths. The memory devices are dynamically configurable through the issuance of a single command propagated serially through all the memory devices from the memory controller in a broadcast operation. Robust operation of the system is ensured by implementing a data output inhibit algorithm, which prevents valid data from being provided to the memory controller when read output control signal is received out of its proper sequence.
Abstract:
A dynamic random access memory (DRAM) is selectively operable in a sleep mode and another mode. The DRAM has data storage cells that are refreshed in the refresh mode. A boosted voltage is provided for the operation of the DRAM. A boosted voltage provider includes a group of charge pump circuits that are selectively activated by a pump control circuit based on a refresh time for refreshing data in the DRAM cells in the sleep mode.
Abstract:
Systems and methods are disclosed that may include a first layer comprising a first redundant memory element, an input/output interface, a first layer fuse box, and a fuse blowing control. These systems and methods also may include a second layer coupled to the first layer through a first connection comprising a second layer memory element and a second layer fuse box coupled to the first redundant memory element. In addition, these systems and methods may further include a redundancy register coupled to the first layer, wherein upon the failure of part of the second layer memory element, the redundancy register provides information to the fuse blowing control that allocates part of the first redundant memory element to provide redundancy for the failed part of the second layer memory element by blowing elements in the first layer fuse box and the second layer fuse box.
Abstract:
A bridge device architecture for connecting discrete memory devices. The bridge device is used in conjunction with a composite memory device including at least one discrete memory device. The bridge device includes a local control interface for connecting to the at least one discrete memory device, a local input/output interface for connecting to the at least one discrete memory device, and a global input/output interface. The global input/output interface receives and provides global memory control signals and also receives and provides write data to and read data from the at least one discrete memory device.
Abstract:
A dynamic random access memory (DRAM) device has an array of DRAM cells of rows by columns. Each DRAM cell of the array is coupled with a wordline of a corresponding row and a bitline of a corresponding column. An entry into and an exit from the self-refresh mode are detected by a mode detector and a self-refresh mode signal is provided. An oscillation circuit generates in response to the self-refresh mode signal generates a basic time period. A first frequency divider/time period multiplier changes the basic time period in accordance with a process variation factor relating to the DRAM device. A second frequency divider/time period multiplier further changes the changed time period in accordance with a temperature change factor relating to the DRAM device. In the self-refresh mode, data stored in the DRAM cells is refreshed. In accordance with the two factors, the DRAM devices perform and achieve reliable self-refresh for variable DRAM cell retention time.
Abstract:
A dynamic random access memory (DRAM) is selectively operable in a sleep mode and another mode. The DRAM has data storage cells that are refreshed in the refresh mode. A boosted voltage is provided for the operation of the DRAM. A boosted voltage provider includes a group of charge pump circuits that are selectively activated by a pump control circuit based on a refresh time for refreshing data in the DRAM cells in the sleep mode.
Abstract:
A method for programming NAND flash cells to minimize program stress while allowing for random page programming operations. The method includes asymmetrically precharging a NAND string from a positively biased source line while the bitline is decoupled from the NAND string, followed by the application of a programming voltage to the selected memory cell, and then followed by the application of bitline data. After asymmetrical precharging and application of the programming voltage, all the selected memory cells will be set to a program inhibit state as they will be decoupled from the other memory cells in their respective NAND strings, and their channels will be locally boosted to a voltage effective for inhibiting programming. A VSS biased bitline will discharge the locally boosted channel to VSS, thereby allowing programming of the selected memory cell to occur. A VDD biased bitline will have no effect on the precharged NAND string, thereby maintaining a program inhibited state of that selected memory cell.
Abstract:
A method for improving sub-word line response comprises generating a variable substrate bias determined by at least one user parameter. The variable substrate bias is applied to a sub-word line driver in a selected sub-block of a memory. A voltage disturbance on a sub-word line in communication with the sub-word line driver is minimized by modifying a variable substrate bias of the sub-word line driver to change a transconductance of the sub-word line driver thereby.
Abstract:
An apparatus and method of page program operation is provided. When performing a page program operation with a selected memory device, a memory controller loads the data into the page buffer of one selected memory device and also into the page buffer of another selected memory device in order to store a back-up copy of the data. In the event that the data is not successfully programmed into the memory cells of the one selected memory device, then the memory controller recovers the data from the page buffer of the other memory device. Since a copy of the data is stored in the page buffer of the other memory device, the memory controller does not need to locally store the data in its data storage elements.
Abstract:
Status indication in a system having a plurality of memory devices is disclosed. A memory device in the system includes a plurality of data pins for connection to a data bus. The memory device also includes a status pin for connection to a status line that is independent from the data bus. The memory device also includes first circuitry for generating, upon completion of a memory operation having a first duration, a strobe pulse of a second duration much shorter than the first duration. The strobe pulse provides an indication of the completion of the memory operation. The memory device also includes second circuitry for outputting the strobe pulse onto the status line via the status pin.