Abstract:
A memory device includes a driver that drives a data line connected with an external device, an internal ZQ manager that generates an internal ZQ start signal, a selector that selects one of the internal ZQ start signal and a ZQ start command from the external device, based on a ZQ mode, a ZQ calibration engine that generates a ZQ code by performing ZQ calibration in response to a selection result of the selector, and a ZQ code register that loads the ZQ code onto the driver in response to a ZQ calibration command from the external device.
Abstract:
A method of operating memory devices disposed in different ranks of a multi-rank memory device and sharing a signal line includes receiving, in all of the memory devices included in the multi-rank memory device, on-die termination (ODT) state information of the signal line. The method further includes storing, in each of the memory devices of the multi-rank memory device, the ODT state information of the signal line in a mode register. The method further includes generating, in each of the memory devices of the multi-rank memory device, a control signal based on the ODT state information of the signal line stored in the mode register. The method further includes changing, in each of the memory devices of the multi-rank memory device, an ODT setting of the signal line in response to the control signal.
Abstract:
An on-die termination (ODT) circuit includes a calibration unit, an offset-code generating unit, an adder, and an ODT unit. The calibration unit generates a pull-up code and a pull-down code. The offset-code generates a pull-up offset code and a pull-down offset code based on a mode-register-set signal, the pull-up code, and the pull-down code. The adder adds the pull-up offset code and the pull-down offset code to the pull-up code and the pull-down code, respectively, and generates a pull-up calibration code and a pull-down calibration code. The ODT unit changes ODT resistance in response to the pull-up calibration code and the pull-down calibration code.
Abstract:
A memory device includes a driver that drives a data line connected with an external device, an internal ZQ manager that generates an internal ZQ start signal, a selector that selects one of the internal ZQ start signal and a ZQ start command from the external device, based on a ZQ mode, a ZQ calibration engine that generates a ZQ code by performing ZQ calibration in response to a selection result of the selector, and a ZQ code register that loads the ZQ code onto the driver in response to a ZQ calibration command from the external device.
Abstract:
An integrated circuit device includes a stack of integrated circuit memory dies having a plurality of through-substrate vias (TSVs) extending therethrough, and a buffer die electrically coupled to the plurality of TSVs. The buffer die includes a test interface circuit, which is configured to: (i) generate a plurality of internal test signals, which are synchronized with a second clock signal having a second frequency, from at least one control code, and from a plurality of external test signals, which are synchronized with a first clock signal having a first frequency less than the second frequency, and (ii) provide the plurality of internal test signals to at least one of the memory dies in said stack during a first test mode. The second frequency may be greater than three (3) times the first frequency.
Abstract:
A semiconductor memory device may include a cell array comprising a plurality of memory cells, each memory cell connected to a word line and a bit line, the cell array divided into a plurality of blocks, each block including a plurality of word lines, the plurality of blocks including at least a first defective block; a nonvolatile storage circuit configured to store address information of the first defective block, and to output the address information to an external device; and a fuse circuit configured to cut off an activation of word lines of the first defective block.
Abstract:
A use time managing method of a semiconductor device may include (1) measuring an amount of accumulated operation time of the semiconductor device and when the amount is reached to a predetermined value, generating a unit storage activation signal; (2) repeating step (1) to generate one or more additional unit storage activation signals, thereby generating a plurality of unit storage activation signals, wherein the predetermined values are different for each repeating step; (3) storing data indicating each occurrence of generating the unit storage activation signals; and (4) detecting use time of the semiconductor device based on the cumulatively stored data.
Abstract:
A semiconductor memory device includes a memory cell array, sub word-line drivers and power selection switches. The memory cell array includes memory cell rows coupled to word lines. The sub word line drivers are coupled to the word lines. The power selection switches are coupled to the sub word-line drivers. Each power selection switch controls a deactivation voltage level of a first word-line activated from the word-lines and an off-voltage level of a second word line adjacent to the first word line so that the deactivation voltage level and the off-voltage level have at least one of a ground voltage, a first negative voltage and a second negative voltage. The ground voltage, the first negative voltage and the second negative voltage have different voltage levels from each other.
Abstract:
A refresh address generator may include a lookup table including a first portion storing a first group of addresses associated with a first data retention time, and a second portion storing a second group of addresses associated with a second data retention time different from the first data retention time, wherein the addresses of the first portion are more frequently accessed than the addresses of the second portion to refresh the memory cells corresponding to the addresses. Systems and methods may also implement such refresh address generation.
Abstract:
A memory device may be provided which includes a memory cell array including a plurality of sub arrays each sub array having a plurality of memory cells connected to bit lines; an address buffer configured to receive a row address and a column address; and a column decoder configured to receive the column address from the address buffer and, for each of the sub arrays, to select a column selection line corresponding to the column address, from among a plurality of column selection lines, based on different offset values applied to the sub arrays, respectively. The selected column selection lines correspond to bit lines having different physical locations, respectively, according to the different offset values.