• Journal of Internet Computing and Services
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• v.6 no.4
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• pp.47-58
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• 2005

There are two major type of flash memory products, namely, NAND-type and NOR-type flash memory. NOR-type flash memory is generally deployed as ROM BIOS code storage because if offers Byte I/O and fast read operation. However, NOR-type flash memory is more expensive than NAND-type flash memory in terms of the cost per byte ratio, and hence NAND type flash memory is more widely used as large data storage such as embedded Linux file systems. In this paper, we designed an efficient flash memory file system based an Embedded system and presented to make up for reduced to Swapping a weak System Performance to flash file system using NAND-type flash memory, then proposed Swapping algorithm insured to an Execution time. Based on Implementation and simulation studies, Then, We improved performance bases on NAND-type flash memory to the requirement of the embedded system.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.1
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• pp.79-89
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• 2014

It has been an increase in consumers who want a high-capacity and fast speed by the newly diffused mobile device(Smart phones, Ultra books, Tablet PC). As a result, the demand for Flash Memory is constantly increasing. Flash Memory is separated by a NAND-type and NOR-type. NAND-type Flash Memory speed is slow, but price is cheaper than the NOR-type Flash Memory. For this reason, NAND-type Flash Memory is widely used in the mobile market. So Fault Detection is very important for Flash Memory Test. In this paper, Proposed PMBIST for Pattern Test of NAND-type Flash Memory improved Fault detection.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.10 no.4
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• pp.115-120
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• 2011

Recently flash memory is widely used in various mobile devices as storage medium. Nonvolatile memory can be divided into two categories: NAND- and NOR-type flash memory. NOR flash memory is mainly used to store instruction codes for operation; while NAND for data storage. However, NAND does show more economical benefits, that is, it is approximately 30~40% cheaper than NOR flash. Therefore it can be useful to improve NAND flash performance by replacing NOR flash with NAND flash combining with various buffer systems.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.6
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• pp.122-130
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• 2013

The demand and the supply are increasing sharply in accordance with the growth of the Memory Semiconductor Industry. The Flash Memory above all is being utilized substantially in the Industry of smart phone, the tablet PC and the System on Chip (SoC). The Flash Memory is divided into the NOR-type Flash Memory and the NAND-type Flash Memory. A lot of study such as the Built-In Self Test (BIST), the Built-In Self Repair (BISR) and the Built-In Redundancy Analysis (BIRA), etc. has been progressed in the NOR-type fash Memory, the study for the Built-In Self Test of the NAND-type Flash Memory has not been progressed. At present, the pattern test of the NAND-type Flash Memory is being carried out using the outside test equipment of high price. The NAND-type Flash Memory is being depended on the outside equipment as there is no Built-In Self Test since the erasure of block unit, the reading and writing of page unit are possible in the NAND-type Flash Memory. The Built-In Self Test equipped with 2 kinds of finite state machine based structure is proposed, so as to carry out the pattern test without the outside pattern test equipment from the NAND-type Flash Memory which carried out the test dependant on the outside pattern test equipment of high price.

• IEMEK Journal of Embedded Systems and Applications
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• v.10 no.3
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• pp.151-156
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• 2015

Recently, an embedded flash memory has been widely used for the Internet of Things(IoT). Due to its nonvolatility, economical feasibility, stability, low power usage, and fast speed. With respect to power consumption, the embedded memory system must consider the most significant design factor. The objective of this research is to design high performance and low power NAND flash memory architecture including a dual buffer as a replacement for NOR flash. Simulation shows that the proposed NAND flash system can achieve better performance than a conventional NOR flash memory. Furthermore, the average memory access time of the proposed system is better that of other buffer systems with three times more space. The use of a small buffer results in a significant reduction in power consumption.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.49 no.4
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• pp.26-33
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• 2012

As the flash memory has increased the market share of data storage in imbedded system and occupied the most of area in a system, It has a profound impact on system reliability. Flash memory is divided NOR/NAND-type according to the cell array structure, and is classified as SLC(Single Level Cell)/MLC(Multi Level Cell) according to reference voltage. Although NAND-type flash memory is slower than NOR-type, but it has large capacity and low cost. Also, By the effect of demanding mobile market, MLC NAND-type is widely adopted for the purpose of the multimedia data storage. Accordingly, Importance of fault detection algorithm is increasing to ensure MLC NAND-type flash memory reliability. There are many researches about the testing algorithm used from traditional RAM to SLC flash memory and it detected a lot of errors. But the case of MLC flash memory, testing for fault detection, there was not much attempt. So, In this paper, Extend SLC NAND-type flash memory fault detection algorithm for testing MLC NAND-type flash memory and try to reduce these differences.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.7
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• pp.636-645
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• 2008

OneNAND flash is a high-performance hybrid flash memory that combines the advantages of both NAND flash and NOR flash. OneNAND flash has not only all virtues of NAND flash but also greatly enhanced read performance which is considered as a downside of NAND flash. As a result, it is widely used in mobile applications such as mobile phones, digital cameras, PMP, and portable game players. However, most of the general purpose operating systems, such as Linux, can not exploit the read performance of OneNAND flash because of the restrictions imposed by their virtual memory system and block I/O architecture. In order to solve that problem, we suggest a new approach called virtual I/O segment. By using virtual I/O segment, the superior read performance of OneNAND flash can be exploited without modifying the existing block I/O architecture and MTD subsystem. Experiments by implementations show that this approach can reduce read latency of OneNAND flash as much as 54%.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.3
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• pp.61-71
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• 2014

As the occupancy rate of the flash memory increases in the storage media market for the embedded system and the semi-conductor industry grows, the demand and supply of flash memory is increasing by a big margin. They are especially used in large quantity in the smart phones, tablets, PC, SSD and Soc(System on Chip) etc. The flash memory is divided into the NOR type and NAND type according to the cell arrangement structure and the NAND type is divided into the SLC(Single Level Cell) and MLC(Multi Level Cell) according to the number of bits that can be stored in each cell. Many tests have been performed on NOR type such as BIST(Bulit-In Self Test) and BIRA(Bulit-In Redundancy Analysis) etc, but there is little study on the NAND type. For the case of the existing BIST, the test can be proceeded using external equipments like ATE of high price. However, this paper is an attempt for the improvement of credibility and harvest rate of the system by proposing the BIST for the MLC NAND type flash memory of Finite State Machine structure on which the pattern test can be performed without external equipment since the necessary patterns are embedded in the interior and which uses the MLC NAND March(x) algorithm and pattern which had been proposed for the MLC NAND type flash memory.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.3
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• pp.710-716
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• 2008

This paper covers the performance evaluation of two flash memory-based file storages, NAND and NOR, which are the major flash types. To evaluate their performances, we set up separate file storages for the two types of flash memories on a PocketPC-based experimental platform. Using the platform, we measured and compared the I/O throughputs in terms of buffer size, amount of used space, and kernel-level write caching. According to the results from our experiments, the overall performance of the NAND-based storage is higher than that of NOR by up to 4.8 and 5.7 times in write and read throughputs, respectively. The experimental results show the relative strengths and weaknesses of the two schemes and provide insights which we believe assist in the design of flash memory-based file storages.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.26-27
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• 2006

To develop tera-bit level SONOS flash memories, SONOS unit memory and 64 bit flash arrays are fabricated. The unit cells have both channel length and width of 30nm. The NAND & NOR arrays are fabricated on SOI wafer and patterned by E-beam. The unit cells represent good write/erase characteristics and reliability characteristics. SSL-NOR array have normal write/erase operation. These researches are leading the realization of Tera-bit level non-volatile nano flash memory.