Embedded Systems: An Integrated Approach by Pearson

74 EMBEDDED SYSTEMS

In NOR-fl ash, cells are connected in parallel to the bit lines facilitating the read-

ing/writing/erasing of each cell individually.  is parallel connection is similar to the

parallel connection of transistors in a CMOS NOR array, and hence the name ‘NOR

fl ash’. In contrast, cells in a NAND fl ash are connected in series.  is diff erence is the

reason for diff erences in the way of usage and the application domain of the two types

of cells.

NOR fl ash is relatively higher speed (than NAND), and here random access is pos-

sible such that data can be read or written in quantities as small as a byte. NAND fl ash,

on the other hand, ...