M29W640GH, M29W640GL, M29W640GT, M29W640GB
Description
1
Description
The M29W640G is a 64 Mbit (8Mb x8 or 4Mb x16) non-volatile memory that can be read,
erased and reprogrammed. These operations can be performed using a single low voltage
(2.7 to 3.6V) supply. On power-up the memory defaults to its Read mode.
The memory is divided into blocks that can be erased independently so it is possible to
preserve valid data while old data is erased. 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 M29W640GH and M29W640GL memory array is organized into 128 uniform Blocks of
64 Kbytes each (or 32 Kwords each).
The M29W640GT and M29W640GB feature an asymmetric block architecture. The devices
have an array of 135 blocks, divided into 8 Parameter Blocks of 8 Kbytes each (or 4 Kwords
each), and 127 Main Blocks of 64 Kbytes each (or 32 Kwords each). The M29W640GT has
the Parameter Blocks at the top of the memory address space while the M29W640GB
locates the Parameter Blocks starting from the bottom.
Blocks are protected by groups to prevent accidental Program or Erase commands from
modifying the memory.
●
●
describes the protection granularity on the M29W640GH and M29W640GL.
and
describe the protection granularity on the M29W640GT and
M29W640GB.
The M29W640G support Asynchronous Random Read and Page Read from all blocks of
the memory array.
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 V
PP
/WP signal is used to enable faster programming of the device. Protection from
Program/Erase operation can be obtained by holding V
PP
/WP to V
SS
:
●
●
On the M29W640GH and M29W640GL, the last and the first block is protected,
respectively.
On the M29W640GT and M29W640GB, the first two and the last two boot blocks are
protected.
The devices feature a full set of Fast Program commands to improve the programming
throughput:
●
●
●
●
2 Byte Program: it is not necessary to raise V
PP
/WP to 12V before issuing this
command
2 Words/4 Bytes Program: it is not necessary to raise V
PP
/WP to 12V before issuing
this command.
4 Words/8 Bytes Program: V
PP
/WP must be raised to 12V before issuing this
command.
Write to Buffer and Program, allowing to program in one shot a buffer of 16 words/32
bytes.
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NUMONYX [ NUMONYX B.V ]
