SUMMARY DESCRIPTION
The M29F040B is a 4 Mbit (512Kb x8) non-volatile memory that can be read, erased and reprogrammed. These operations can be performed using a single 5V 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 M29F040B is fully backward compatible with the M29F040.
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.
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 TSOP32 (8 x 20mm), and PLCC32 packages. It is supplied with all the bits erased (set to ‘1’).
In order to meet environmental requirements, ST offers the M29F040B 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.

■ SINGLE 5V ± 10% SUPPLY VOLTAGE for PROGRAM, ERASE and READ OPERATIONS
■ ACCESS TIME: 45ns
■ PROGRAMMING TIME
   – 8 µs per Byte typical
■ 8 UNIFORM 64 Kbytes MEMORY BLOCKS
■ PROGRAM/ERASE CONTROLLER
   – Embedded Byte Program algorithm
   – Embedded Multi-Block/Chip Erase algorithm
   – Status Register Polling and Toggle Bits
■ ERASE SUSPEND and RESUME MODES
   – Read and Program another Block during Erase Suspend
■ UNLOCK BYPASS PROGRAM COMMAND
   – Faster Production/Batch Programming
■ LOW POWER CONSUMPTION
   – Standby and Automatic Standby
■ 100,000 PROGRAM/ERASE CYCLES per BLOCK
■ 20 YEARS DATA RETENTION
   – Defectivity below 1 ppm/year
   ■ ELECTRONIC SIGNATURE
   – Manufacturer Code: 20h
   – Device Code: E2h
■ ECOPACK® PACKAGES AVAILABLE