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4Mb Smart 3 Boot Block Flash Memory

F45_3.p65 – Rev. 3, Pub. 12/01

©2001, Micron Technology, Inc.

4Mb

SMART 3 BOOT BLOCK FLASH MEMORY

PRODUCTS AND SPECIFICATIONS DISCUSSED HEREIN ARE SUBJECT TO CHANGE BY MICRON WITHOUT NOTICE.

GENERAL DESCRIPTION

The MT28F004B3 (x8) and MT28F400B3 (x16/x8)

are nonvolatile, electrically block-erasable (flash), pro-

grammable memory devices containing 4,194,304 bits

organized as 262,144 words (16 bits) or 524,288 bytes (8

bits). Writing or erasing the device is done with either a

gramming. These devices are fabricated with Micron’s

advanced 0.18µm CMOS floating-gate process.

The MT28F004B3 and MT28F400B3 are organized

into seven separately erasable blocks. To ensure that

critical firmware is protected from accidental erasure or

overwrite, the devices feature a hardware-protected

boot block. Writing or erasing the boot block requires

either applying a super-voltage to the RP# pin or driv-

ing WP# HIGH in addition to executing the normal write

or erase sequences. This block may be used to store

code implemented in low-level system recovery. The

remaining blocks vary in density and are written and

erased with no additional security measures.

Refer to Micron’s Web site (www.micron.com/flash)

for the latest data sheet.

FLASH MEMORY

MT28F004B3

MT28F400B3

3V Only, Dual Supply (Smart 3)

FEATURES

• Seven erase blocks:

16KB/8K-word boot block (protected)

Two 8KB/4K-word parameter blocks

Four main memory blocks

• Smart 3 technology (B3):

• Compatible with 0.3µm Smart 3 device

• Advanced 0.18µm CMOS floating-gate process

• Address access time: 80ns

• 100,000 ERASE cycles

• Industry-standard pinouts

• Inputs and outputs are fully TTL-compatible

• Automated write and erase algorithm

• Two-cycle WRITE/ERASE sequence

• Byte- or word-wide READ and WRITE

(MT28F400B3, 256K x 16/512K x 8)

• Byte-wide READ and WRITE only

(MT28F004B3, 512K x 8)

• TSOP and SOP packaging options

OPTIONS

MARKING

• Timing

80ns access

-8

• Configurations

512K x 8

MT28F004B3

256K x 16/512K x 8

MT28F400B3

• Boot Block Starting Word Address

Top (3FFFFh)

T

Bottom (00000h)

B

• Operating Temperature Range

Commercial (0ºC to +70ºC)

None

Extended (-40ºC to +85ºC)

ET

• Packages

44-pin SOP (MT28F400B3)

SG

48-pin TSOP Type I (MT28F400B3)

WG

40-pin TSOP Type I (MT28F004B3)

VG

NOTE:

application production programming can be used with no

loss of performance.

Part Number Example:

MT28F400B3SG-8 T

40-Pin TSOP Type I 48-Pin TSOP Type I

44-Pin SOP