With the widely promotion of 3D NAND Flash in the market, LDPC has became a key marketing advertisement by all flash vendors. From the point of ECC, there is indeed no more powerful error correction algorithm than LDPC. But on the contrary, there also exists disagreements. Although the LDPC has been used by HDD for years, it is still unverified by the market when used in NAND Flash. In theory, LDPC is also with own defects. 1. The latency time of LDPC is extremely long due to the process of iteration. 2. The Soft Information is necessary. It’s easy to get the Soft Information of HDD at once, but it’s difficult to get the accurate Soft Information of NAND Flash. Once you get the wrong information, the result could be disastrous. Because the LDPC need to calculate the probability with the Soft Information, if the decoder of LDPC gets the wrong Soft Information, it will lead the wrong inform...
If you want to look for a Nand Flash test equipment, Renice have 3 types of Nand Flash Tester for your option, NFA100-E, NFA100 and NFA1000. What can Nand Flash Testers do? How to select a suitable Nand Flash Tester? Let us show more information, you might find the answer here. Brief Introduction NAF100-E , is an extremely powerful and flexible NAND Flash testing platform specially developed for R&D personnel whereby they can extract NAND Flash parameters in a maximal way by using NFA100-E system commands and even reprocess these parameters for eventual product development. User can also realize their specific testing requirements through API or usage of script commands. NAF100 and NAF1000 , is able to test up to 112pcs/1120pcs of NAND Flash at the same time. Besides all functions that NFA100-E has, NFA100 is equipped with high-low temperature chamber so that users are able to make high-low temp. cycle test, humidity and thermal shock test.NFA100 is also ...
The first portion of this article introduces the background of wear leveling and some commonly used algorithm while the second portion covers a kind of wear leveling that can prolong life by three folds: Non-balance Algorithm. Experts may skip directly to the later portion. In order to prolong the life cycle of NAND flash by avoiding some blocks being frequently erased and becoming bad blocks rapidly while the existence of other less erased blocks will cause an unbalance Program/Erase situation that shorten the overall SSD product life as a drawback. There are various algorithm towards wear leveling and garbage collection raised by NAND flash practitioner as strategy to avoid these potential problems. Background of Wear Leveling Algorithm The wear leveling algorithm is based on the basic characteristics of flash memory: 1. Do not support local update (outplace-update that is data in original location cannot be overwrite or change directly, this data will need to be relocated t...
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