Samsung Electronics Co., Ltd.

Joo-Sun Choi

Kwang-il Park

Jung-Hwan Choi

Chul-woo Park

Seung-Jun Bae

Jong-Hoon Kim

Young-Hyun Jun

Chul-Woo Park

Hong-Sun Hwang

Hi-Choon Lee

You-Keun Han

Seung-Jin Seo

Won-Il Bae

Won-Chang Jung

Seok-Il Kim

Sung-Min Yim

Sang-hyup Kwak

Kwan-Yong Jin

A refresh method for a volatile memory device includes refreshing memory cells of a first set of rows of an array at a first refresh rate having a first refresh period, the first refresh rate being a lower rate having a longer refresh period than a second refresh rate having a second refresh period, wherein each memory cell in the first set of rows of the array has a retention time longer than the first refresh period; and refreshing memory cells of a second set of rows of the array at a third refresh rate having a third refresh period, the third refresh rate being a higher rate having a shorter refresh period than the second refresh rate having the second refresh period, wherein at least one memory cell of each row of the second set of rows has a retention time longer than the third refresh period and shorter than the first refresh period. The second refresh period corresponds to a refresh period defined in a standard for the volatile memory device.

Refresh method, refresh address generator, volatile memory device including the same

In an embodiment, a semiconductor memory device includes a clock latency that can be controlled responsive to whether or not an output order of burst data is reordered. The semiconductor memory device may comprise a control unit and a latency control unit. The control unit may generate a latency control signal having a logic level that varies depending on whether or not an output order of burst data is reordered. The latency control unit may control a latency value in response to the latency control signal. The semiconductor memory device and the method of controlling the latency value responsive to a reordering of the burst data allow for an optimally fast memory access time.

Semiconductor memory device and method for controlling clock latency according to reordering of burst data

An input/output (IO) interface includes a data encoder which encodes each of a plurality of pieces of parallel data having different timings and generates a plurality of pieces of encoded data, and an alternating current (AC) coupling transmission unit which transmits the plurality of encoded data in an AC coupling method. The data encoder compares first parallel data with second parallel data from among the plurality of pieces of parallel data on a bit-by-bit basis and obtains the number of bits whose logic states have transited between the first parallel data and the second parallel data. When the number of bits whose logic states have transited is greater than or equal to a reference number of bits, the data encoder inverts bit values of the second parallel data to generate the encoded data. When the number of bits whose logic states have transited is less than the reference number of bits, the data encoder maintains the bit values of the second parallel data to generate the encoded data.

Input/output (IO) interface and method of transmitting IO data

A memory module includes a plurality of data ports configured to receive/transmit associated data and a plurality of memory devices. The plurality of memory devices include a first set of the memory devices in at least one rank, each memory device of the first set being coupled to each of the associated data ports, and a second set of the memory devices in at least one other rank, each memory device of the second set being configured to receive/transmit the associated data for the memory device through at least each associated memory device of the first set.

Memory modules and memory systems having the same

A memory module includes a port configured to receive write data and command/address signals and multiple memory devices. The multiple memory devices include a first set of the memory devices, each memory device of the first set coupled to the port, and a second set of the memory devices, each memory device of the second set configured to receive associated write data and associated command/address signals for the memory device through at least one of the other memory devices of the first set and the second set.

Growing community of inventors

Gyeonggi-do, South Korea

Joo-Sun Choi