8

8Mb Smart 3 Boot Block Flash Memory

Micron Technology, Inc., reserves the right to change products or specifications without notice.

Q10_3.p65 – Rev. 3, Pub. 10/01

©2001, Micron Technology, Inc.

8Mb

SMART 3 BOOT BLOCK FLASH MEMORY

Figure 1

Memory Address Maps

Top Boot

MT28F008B3/800B3xx-xxT

Bottom Boot

MT28F008B3/800B3xx-xxB

while the ISM is active. However, there are restrictions

on what commands are allowed in this condition. See

the Command Execution section for more detail.

DEEP POWER-DOWN MODE

To allow for maximum power conservation, the

MT28F800B3 and MT28F008B3 feature a very low cur-

rent, deep power-down mode. To enter this mode, the

power-down also clears the status register and sets the

ISM to the read array mode.

MEMORY ARCHITECTURE

The MT28F800B3 and MT28F008B3 memory array

architecture is designed to allow sections to be erased

without disturbing the rest of the array. The array is

divided into eleven addressable blocks that vary in size

and are independently erasable. When blocks rather than

the entire array are erased, total device endurance is

enhanced, as is system flexibility. Only the ERASE func-

tion is block-oriented. All READ and WRITE operations

are done on a random-access basis.

The boot block is protected from unintentional ERASE

or WRITE with a hardware protection circuit which re-

quires that a super-voltage be applied to RP# or that the

WP# pin be driven HIGH before erasure is commenced.

The boot block is intended for the core firmware required

for basic system functionality. The remaining ten blocks

do not require that either of these two conditions be met

before WRITE or ERASE operations.

BOOT BLOCK

The hardware-protected boot block provides extra

security for the most sensitive portions of the firmware.

This 16KB block may only be erased or written when the

of 12V or when the WP# pin is HIGH. During a WRITE or

or the WP# pin held HIGH until the WRITE or ERASE is

completed. (The WP# pin does not apply to the SOP

the boot block is written to or erased.

FFFFFh

FC000h

FBFFFh

FA000h

F9FFFh

F8000h

F7FFFh

E0000h

DFFFFh

C0000h

BFFFFh

A0000h

9FFFFh

80000h

7FFFFh

60000h

5FFFFh

40000h

3FFFFh

20000h

1FFFFh

00000h

16KB Boot Block

8KB Parameter Block

8KB Parameter Block

96KB Main Block

128KB Main Block

128KB Main Block

128KB Main Block

128KB Main Block

128KB Main Block

128KB Main Block

128KB Main Block

BYTE ADDRESS

7FFFFh

7E000h

7DFFFh

7D000h

7CFFFh

7C000h

7BFFFh

70000h

6FFFFh

60000h

5FFFFh

50000h

4FFFFh

40000h

3FFFFh

30000h

2FFFFh

20000h

1FFFFh

10000h

0FFFFh

00000h

WORD ADDRESS

128KB Main Block

128KB Main Block

128KB Main Block

128KB Main Block

128KB Main Block

128KB Main Block

128KB Main Block

96KB Main Block

8KB Parameter Block

8KB Parameter Block

16KB Boot Block

BYTE ADDRESS

FFFFFh

E0000h

DFFFFh

C0000h

BFFFFh

A0000h

9FFFFh

80000h

7FFFFh

60000h

5FFFFh

40000h

3FFFFh

20000h

1FFFFh

08000h

07FFFh

06000h

05FFFh

04000h

03FFFh

00000h

7FFFFh

70000h

6FFFFh

60000h

5FFFFh

50000h

4FFFFh

40000h

3FFFFh

30000h

2FFFFh

20000h

1FFFFh

10000h

0FFFFh

04000h

03FFFh

03000h

02FFFh

02000h

01FFFh

00000h

WORD ADDRESS