Flash memory is often used in embedded systems as a means to store data and information, providing the system with the needed instructions to operate. Two of the most widely used types of Flash memory include NOR and NAND Flash. 

What is Flash Memory?

Flash memory is a non-volatile memory storage device that can be electrically erased and reprogrammed. Non-volatile memory means that the memory device will retain the stored data even when the system is powered off. You can also find Flash Programmers for ARM MCUs for the best performance.

One of the reasons that Flash memory is often used in embedded systems is its ability to erase data in blocks rather than by individual bytes. Because Flash memory needs to be erased before it can be programmed, this helps expedite the process and allows for faster programming.

There are several different types of Flash memory, but the most commonly used include NOR and NAND Flash. Both of these types of Flash memory store data in memory cells made from floating-gate transistors. NOR and NAND Flash get their names from the type of logic gate used in the cell and differ through their architecture and purpose.

NAND and NOR Flash Architecture and Purpose

NOR flash is optimized for random access capabilities, which means it is capable of accessing data in any order and does not require following a sequence of storage locations. In its internal circuit configuration, each of NOR Flash’s memory cells is connected in parallel; one end of the memory cell is connected to the source line and the other end is connected to the bit line. Because of this, the system is able to access individual memory cells.

NAND Flash, on the other hand, is optimized for high-density data storage and gives up the ability for random access capabilities. Unlike NOR Flash, NAND Flash cells are connected, usually eight memory transistors at the time, in a series to the bit line called a string. Here, the source of one cell is connected to the drain of the next one.