To simplify the life of embedded designers looking to store code on NOR flash systems with densities beyond 512Mb, Winbond is offering QspiNAND products with the same SPI interface with a cost effective QspiNAND flash at 1Gb and 2Gb densities. While NOR flash is more cost effective at lower densities, NAND flash is more cost effective at 512Mb and above.
Benefits of Using Winbond QspiNAND Flash
NAND flash memory requires a controller to manage functions like detecting and correcting errors in some memory locations, managing memory blocks with errors, and relocating locations with errors to new locations that are error-free.
These QspiNAND family of products have built-in ECC (Error Correcting Code) that detects and corrects errors and offers contiguous good memory (bad block management), which offloads these functions from the controller and supports Executive-in-Place (XiP) functionality, in which an SoC or processor executes application code directly from the external flash memory without shadowing it to DRAM.
Code Shadowing
Typically in most systems, code stored in flash, is transferred to DRAM for faster execution of code with the processor. This is known as code shadowing. System designers are always looking for products that can transfer the code very quickly from flash to DRAM. Winbond’s “continuous read” functionality transfers the contents of NAND very quickly to the DRAM.
