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Memory array, Device operation – Rainbow Electronics AT45DB011D User Manual

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3639J–DFLASH–11/2012

AT45DB011D

4.

Memory Array

To provide optimal flexibility, the memory array of the AT45DB011D is divided into three levels of
granularity comprising of sectors, blocks, and pages. The “Memory Architecture Diagram” illus-
trates the breakdown of each level and details the number of pages per sector and block. All
program operations to the DataFlash occur on a page-by-page basis. The erase operations can
be performed at the chip, sector, block or page level.

Figure 4-1.

Memory Architecture Diagram

5.

Device Operation

The device operation is controlled by instructions from the host processor. The list of instructions
and their associated opcodes are contained in

Tables 15-1 through 15-7

. A valid instruction

starts with the falling edge of CS followed by the appropriate 8-bit opcode and the desired buffer
or main memory address location. While the CS pin is low, toggling the SCK pin controls the
loading of the opcode and the desired buffer or main memory address location through the SI
(serial input) pin. All instructions, addresses, and data are transferred with the most significant
bit (MSB) first.

Buffer addressing for the DataFlash standard page size (264-bytes) is referenced in the data-
sheet using the terminology BFA8 - BFA0 to denote the nine address bits required to designate
a byte address within a buffer. Main memory addressing is referenced using the terminology
PA8 - PA0 and BA8 - BA0, where PA8 - PA0 denotes the nine address bits required to designate
a page address and BA8 - BA0 denotes the nine address bits required to designate a byte
address within the page.

For the “Power of 2” binary page size (256-bytes), the Buffer addressing is referenced in the
datasheet using the conventional terminology BFA7 - BFA0 to denote the 8 address bits
required to designate a byte address within a buffer. Main memory addressing is referenced
using the terminology A16 - A0, where A16 - A8 denotes the nine address bits required to desig-
nate a page address and A7 - A0 denotes the eight address bits required to designate a byte
address within a page.

SECTOR 0a = 8 Pages

2,048-/2,112-bytes

SECTOR 0b = 120 Pages

31,744-/32,726-bytes

Block = 2,048-/2,112-bytes

8 Pages

SECTOR 0a

SECT

OR 0b

Page = 256-/264-bytes

PAGE 0

PAGE 1

PAGE 6

PAGE 7

PAGE 8

PAGE 9

PAGE 510

PAGE 511

BLOCK 0

PAGE 14

PAGE 15

PAGE 16

PAGE 17

PAGE 18

BLOCK 1

SECTOR ARCHITECTURE

BLOCK ARCHITECTURE

PAGE ARCHITECTURE

BLOCK 0

BLOCK 1

BLOCK 14

BLOCK 15

BLOCK 16

BLOCK 17

BLOCK 62

BLOCK 63

BLOCK 30

BLOCK 31

BLOCK 32

BLOCK 33

SECT

OR 1

SECTOR 3 = 128 Pages

32,768-/33,792-bytes

BLOCK 2

SECTOR 1 = 128 Pages

32,768-/33,792-bytes

SECTOR 2 = 128 Pages

32,768-/33,792-bytes