The Design And Implement Of FPGA-Based Multi-Chip NAND FLASH Parallel Storage Controller

With the development of embedded system, data storage requirements are growing rapidly. Now FLASH is being more and more widely used for their characteristics such as fast speed, high density, Non-volatile, erasable and so on. There are mainly two kinds of FLASH, NOR FLASH and NAND FLASH, NAND FLASH has a smaller size, faster write and erase speed, more endurance, and lower per bit price, so has becoming the ideal device for large data storage.FLASH-based solid state disk:using FLASH chips as the storage medium, that is what we usually refer to the SSD. Compared to traditional hard disk, it uses solid state electronic memory chip arrays made of internal mechanism. Therefore, SSD has faster read speed, no noise, fat low in calories, no mechanical failure, greater operating temperature range, small size, light weight, anti-vibration advantages. Although there are shortcomings of small capacity, high cost and the data is difficult to restore, however, the technology of SSD develops with the development of technology, so SSD will be widely used in future.The control logic of NAND FLASH is more complex, data and address using the same bus to achieve serial read, random read speed is slow and can not be random byte programing. So this paper investigates a multi-chip NAND FLASH parallel storage controller design based on Xilinx Spartan-3E with a SRAM interface, so the processor can operate NAND FLASH by SRAM interface standard without the need to consider the NAND FLASH interface, and easy to be used in other expansion applications.The FPGA-based multi-chip NAND FLASH parallel storage controller realizes interface conversion, transfers the complex and not common NAND interface to simple and common SRAM interface, and can control the read and write operation of NAND FLASH; implements ECC function to verify the read and write data operations, improves processing efficiency; controls multi-chip NAND to expand capacity and improve the parallel processing capability, to facilitate the achievement of SSD. In summary, the FPGA-based multi-chip NAND FLASH parallel storage controller, not only has the value of theoretical research, but also has practical value in SSD design.