AM29F040B-150 View Datasheet(PDF) - Advanced Micro Devices
Part Name
Description
Manufacturer
AM29F040B-150 Datasheet PDF : 30 Pages
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PRELIMINARY
GENERAL DESCRIPTION
The Am29F040B is a 4 Mbit, 5.0 volt-only Flash mem-
ory organized as 524,288 Kbytes of 8 bits each. The
512 Kbytes of data are divided into eight sectors of 64
Kbytes each for flexible erase capability. The 8 bits of
data appear on DQ0–DQ7. The Am29F040B is offered
in 32-pin PLCC, TSOP, and PDIP packages. This de-
vice is designed to be programmed in-system with the
standard system 5.0 volt VCC supply. A 12.0 volt VPP is
not required for write or erase operations. The device
can also be programmed in standard EPROM pro-
grammers.
This device is manufactured using AMD’s 0.35 µm
process technology, and offers all the features and ben-
efits of the Am29F040, which was manufactured using
0 . 5 µ m p r o c e s s t e c h n o l o gy. I n a d d t i o n , t h e
Am29F040B has a second toggle bit, DQ2, and also
offers the ability to program in the Erase Suspend
mode.
The standard Am29F040B offers access times of 55,
70, 90, 120, and 150 ns, allowing high-speed micropro-
cessors to operate without wait states. To eliminate bus
contention the device has separate chip enable (CE#),
write enable (WE#) and output enable (OE#) controls.
The device requires only a single 5.0 volt power sup-
ply for both read and write functions. Internally gener-
ated and regulated voltages are provided for the
program and erase operations.
The device is entirely command set compatible with the
JEDEC single-power-supply Flash standard. Com-
mands are written to the command register using stan-
dard microprocessor write timings. Register contents
serve as input to an internal state-machine that con-
trols the erase and programming circuitry. Write cycles
also internally latch addresses and data needed for the
programming and erase operations. Reading data out
of the device is similar to reading from other Flash or
EPROM devices.
Device programming occurs by executing the program
command sequence. This initiates the Embedded
Program algorithm—an internal algorithm that auto-
matically times the program pulse widths and verifies
proper cell margin.
Device erasure occurs by executing the erase com-
mand sequence. This initiates the Embedded Erase
algorithm—an internal algorithm that automatically
preprograms the array (if it is not already programmed)
before executing the erase operation. During erase, the
device automatically times the erase pulse widths and
verifies proper cell margin.
The host system can detect whether a program or
erase operation is complete by reading the DQ7 (Data#
Polling) and DQ6 (toggle) status bits. After a program
or erase cycle has been completed, the device is ready
to read array data or accept another command.
The sector erase architecture allows memory sectors
to be erased and reprogrammed without affecting the
data contents of other sectors. The device is fully
erased when shipped from the factory.
Hardware data protection measures include a low
VCC detector that automatically inhibits write opera-
tions during power transitions. The hardware sector
protection feature disables both program and erase
operations in any combination of the sectors of mem-
ory. This can be achieved via programming equipment.
The Erase Suspend feature enables the user to put
erase on hold for any period of time to read data from,
or program data to, any sector that is not selected for
erasure. True background erase can thus be achieved.
The system can place the device into the standby
mode. Power consumption is greatly reduced in
this mode.
AMD’s Flash technology combines years of Flash
memory manufacturing experience to produce the
highest levels of quality, reliability and cost effective-
ness. The device electrically erases all bits within a
sector simultaneously via Fowler-Nordheim tunnel-
ing. The data is programmed using hot electron injec-
tion.
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Am29F040B
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