Manuale d’uso / di manutenzione del prodotto Flash Memory del fabbricante M-Systems Flash Disk Pioneers
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White Paper Implementing MLC NAND Flash for Cost-Effective, High-Capacity Memory Written by: Raz Dan and Rochelle Singer JANUARY 2003 91-SR-014-02-8L, REV 1.
Implementing MLC NAND Flash for Cost -Effective, High-Capacity Memory 91-SR-014-0 2-8L 2 Introduction Multi-Level Cell (MLC) technology greatly reduces flash die size to achieve a breakthrough cost structure. It does this by st oring 2 bits of data per physical cell in stead of the traditi onal 1 bit per cell, using Binary flash technology.
Implementing MLC NAND Flash for Cost -Effective, High-Capacity Memory 91-SR-014-0 2-8L 3 of NOR flash and achieving barely adequate reliability, but it has serious limita tions: its performance is far slower than standard NOR flash.
Implementing MLC NAND Flash for Cost -Effective, High-Capacity Memory 91-SR-014-0 2-8L 4 e - Oxide Floating Gate Select Gate Source Dr ain Substrate Progr am (Inject electrons) Erase (Remov e electron.
Implementing MLC NAND Flash for Cost -Effective, High-Capacity Memory 91-SR-014-0 2-8L 5 MLC Benefits and Limitations MLC high-density design innovations reduce the s ilicon die size, which is the major element contributing to overall device cost.
Implementing MLC NAND Flash for Cost -Effective, High-Capacity Memory 91-SR-014-0 2-8L 6 Read Disturb Errors The read disturb effect causes a page read operati on to induce a permanent, bit value change in one of the read bits. In Binary flash technology based on a 0.
Implementing MLC NAND Flash for Cost -Effective, High-Capacity Memory 91-SR-014-0 2-8L 7 Sustained Read When comparing sustained read performance values in real-world scenarios for Binary Flash with MLC, the gap lessens considerably : MLC performance is 98 percent of Binary flash performance.
Implementing MLC NAND Flash for Cost -Effective, High-Capacity Memory 91-SR-014-0 2-8L 8 Overcoming MLC Limitations Because MLC technology can potentially bring the industry breakth rough cost and siz.
Implementing MLC NAND Flash for Cost -Effective, High-Capacity Memory 91-SR-014-0 2-8L 9 Table 1 maps the various features of x2 technology agai nst the three major ar eas of MLC limitations that they overcome. The rem ainder of this se ction explains how each feature ach ieves these enhancements in Mobile DiskOnChip G3.
Implementing MLC NAND Flash for Cost -Effective, High-Capacity Memory 91-SR-014-0 2-8L 10 Enhanced EDC and ECC The Error Detection Code (EDC) and Error Corr ection Code (ECC) devel oped for x2 technology is based on M-Systems’ highly effective combinati on used in previous generation DiskOnChip products.
Implementing MLC NAND Flash for Cost -Effective, High-Capacity Memory 91-SR-014-0 2-8L 11 Efficient Bad Block Handling x2 technology handles bad blocks, which can be randomly present in flash m edia, by enabling unaligned block access to two planes. Bad blocks are mapped individually on each plane, as shown in Figure 4.
Implementing MLC NAND Flash for Cost -Effective, High-Capacity Memory 91-SR-014-0 2-8L 12 MultiBurst To improve MLC read performance rates, x2 te chnology incorporates a f eature called MultiBurst. MultiBurst enables parallel read acces s from two 16-bit planes to the flash contro ller, thereby achieving the desired output data rate for the host.
Implementing MLC NAND Flash for Cost -Effective, High-Capacity Memory 91-SR-014-0 2-8L 13 Parallel Multiplane Access As discussed earlier, the MLC flash media is built of two planes that can operate in parallel. This architecture is one of the most powerful, x2 technology innovations, doubli ng read, write and erase performance.
Implementing MLC NAND Flash for Cost -Effective, High-Capacity Memory 91-SR-014-0 2-8L 14 How to Contact Us Website: http://www.m-sys.com General Information: info@m-sys.com Technical Information: techsupport@m-sys.com USA M-Systems Inc. 8371 Central Ave, Suite A Newark CA 94560 Phone: +1-510-494-2090 Fax: +1-510-494-5545 Taiwan M-Systems Asia Ltd.
Un punto importante, dopo l’acquisto del dispositivo (o anche prima di acquisto) è quello di leggere il manuale. Dobbiamo farlo per diversi motivi semplici:
Se non hai ancora comprato il M-Systems Flash Disk Pioneers Flash Memory è un buon momento per familiarizzare con i dati di base del prodotto. Prime consultare le pagine iniziali del manuale d’uso, che si trova al di sopra. Dovresti trovare lì i dati tecnici più importanti del M-Systems Flash Disk Pioneers Flash Memory - in questo modo è possibile verificare se l’apparecchio soddisfa le tue esigenze. Esplorando le pagine segenti del manuali d’uso M-Systems Flash Disk Pioneers Flash Memory imparerai tutte le caratteristiche del prodotto e le informazioni sul suo funzionamento. Le informazioni sul M-Systems Flash Disk Pioneers Flash Memory ti aiuteranno sicuramente a prendere una decisione relativa all’acquisto.
In una situazione in cui hai già il M-Systems Flash Disk Pioneers Flash Memory, ma non hai ancora letto il manuale d’uso, dovresti farlo per le ragioni sopra descritte. Saprai quindi se hai correttamente usato le funzioni disponibili, e se hai commesso errori che possono ridurre la durata di vita del M-Systems Flash Disk Pioneers Flash Memory.
Tuttavia, uno dei ruoli più importanti per l’utente svolti dal manuale d’uso è quello di aiutare a risolvere i problemi con il M-Systems Flash Disk Pioneers Flash Memory. Quasi sempre, ci troverai Troubleshooting, cioè i guasti più frequenti e malfunzionamenti del dispositivo M-Systems Flash Disk Pioneers Flash Memory insieme con le istruzioni su come risolverli. Anche se non si riesci a risolvere il problema, il manuale d’uso ti mostrerà il percorso di ulteriori procedimenti – il contatto con il centro servizio clienti o il servizio più vicino.
