M29W400DT datasheet(6/48 Pages) STMICROELECTRONICS

6 / 48 page

Description

M29W400DT, M29W400DB

6/48

Description

The M29W400D is a 4 Mbit (512 Kb x 8 or 256 Kb x 16) non-volatile memory that can be

read, erased and reprogrammed. These operations can be performed using a single low

voltage (2.7 to 3.6 V) supply. On power-up the memory defaults to its Read mode where it

can be read in the same way as a ROM or EPROM.

The memory is divided into blocks that can be erased independently so it is possible to

preserve valid data while old data is erased. Each block can be protected independently to

prevent accidental Program or Erase commands from modifying the memory. Program and

Erase commands are written to the command interface of the memory. An on-chip

Program/Erase controller simplifies the process of programming or erasing the memory by

taking care of all of the special operations that are required to update the memory contents.

The end of a program or erase operation can be detected and any error conditions

identified. The command set required to control the memory is consistent with JEDEC

standards.

The blocks in the memory are asymmetrically arranged, see Figure 5 and Figure 6, Block

addresses. The first or last 64 Kbytes have been divided into four additional blocks. The

16 Kbyte boot block can be used for small initialization code to start the microprocessor, the

two 8 Kbyte parameter blocks can be used for parameter storage and the remaining

32 Kbyte is a small main block where the application may be stored.

Chip Enable, Output Enable and Write Enable signals control the bus operation of the

memory. They allow simple connection to most microprocessors, often without additional

logic.

The memory is offered in SO44, TSOP48 (12 x 20 mm), TFBGA48 0.8 mm pitch (6 x 9 mm

and 6 x 8 mm) packages. The memory is supplied with all the bits erased (set to ’1’).

In order to meet environmental requirements, ST offers the M29W400D in ECOPACK®

packages. ECOPACK packages are Lead-free. The category of second level interconnect is

marked on the package and on the inner box label, in compliance with JEDEC Standard

JESD97. The maximum ratings related to soldering conditions are also marked on the inner

box label. ECOPACK is an ST trademark. ECOPACK specifications are available at:

M29W400DT Datasheet(PDF) 6 Page - STMicroelectronics