Commands scheduling optimized flash controller for high bandwidth SSD application

High Capacity and High bandwidth are the sharpest swords that help SSD expand the storage market at an inspiring pace. Core control logic of SSD is composed of FTL and FC Both FTL and FC impacts greatly on the bandwidth. Conventional FC can only support ONFI standard common set commands and drive a single NAND flash, which demonstrate its limitation in high capacity and high bandwidth application. Improved FC use "two plane address translation" to achieve high performance at program operation, somehow the rule is not always perfect during read operation. The proposed FC structure uses different scheduling rules "read page cache" at read operation by monitoring command pool that works as interface between FTL and FC Comparison is made between "read page cache" scheduling and "two plane address translation" in the basis of "read page operation" to reflect the superiority of the proposed scheme at read operation bandwidth improvement effort. The bandwidth of the proposed structure and scheduling scheme during read operation increase by 51.5% and greater, up to 72.66% for reasonable data pattern, compared with the operation scheduling common "read page" command, while "multi-plane read page" improved by 45.9% at most.