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Am70PDL127BDH/Am70PDL129BDH
November 25, 2003
A D V A N C E I N F O R M A T I O N
GENERAL DESCRIPTION (LV640M)
The Am29LV640MH is a 64 Mbit, 3.0 volt single power
supply flash memory device organized as 4,194,304
words. The device has an 8-bit/16-bit bus and can be
programmed either in the host system or in standard
EPROM programmers.
An access time of 110 ns is available. Each device re-
quires only a
single 3.0 volt power supply
for both
read and write functions. In addition to a V
CC
input, a
high-voltage
accelerated program (ACC)
feature pro-
vides shorter programming times through increased
current on the WP#/ACC input. This feature is in-
tended to facilitate factory throughput during system
production, but may also be used in the field if desired.
The device is entirely command set compatible with
the
JEDEC single-power-supply Flash standard
.
Commands are written to the device using standard
microprocessor write timing. Write cycles also inter-
nally latch addresses and data needed for the pro-
gramming and erase operations.
The
sector erase architecture
allows memory sec-
tors to be erased and reprogrammed without affecting
the data contents of other sectors. The device is fully
erased when shipped from the factory.
Device programming and erasure are initiated through
command sequences. Once a program or erase oper-
ation has begun, the host system need only poll the
DQ7 (Data# Polling) or DQ6 (toggle)
status bits
or
monitor the
Ready/Busy# (RY/BY#)
output to deter-
mine whether the operation is complete. To facilitate
programming, an
Unlock Bypass
mode reduces com-
mand sequence overhead by requiring only two write
cycles to program data instead of four.
The
Versatile I/O
(V
IO
) control allows the host sys-
tem to set the voltage levels that the device generates
and tolerates on the CE# control input and DQ I/Os to
the same voltage level that is asserted on the V
IO
pin.
Refer to the
Ordering Information
section for valid V
IO
options.
Hardware data protection
measures include a low
V
CC
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 sectors of memory.
This can be achieved in-system or via programming
equipment.
The
Erase Suspend/Erase Resume
feature allows
the host system to pause an erase operation in a given
sector to read or program any other sector and then
complete the erase operation. The
Program Sus-
pend/Program Resume
feature enables the host sys-
tem to pause a program operation in a given sector to
read any other sector and then complete the program
operation.
The
hardware RESET# pin
terminates any operation
in progress and resets the device, after which it is then
ready for a new operation. The RESET# pin may be
tied to the system reset circuitry. A system reset would
thus also reset the device, enabling the host system to
read boot-up firmware from the Flash memory device.
The device reduces power consumption in the
standby mode
when it detects specific voltage levels
on CE# and RESET#, or when addresses have been
stable for a specified period of time.
The
Write Protect (WP#)
feature protects the first or
last sector by asserting a logic low on the WP#/ACC
pin. The protected sector will still be protected even
during accelerated programming.
The
SecSi
(Secured Silicon) Sector
provides a
128-word area for code or data that can be perma-
nently protected. Once this sector is protected, no fur-
ther changes within the sector can occur.
AMD MirrorBit flash technology combines years of
Flash memory manufacturing experience to produce
the highest levels of quality, reliability and cost effec-
tiveness. The device electrically erases all bits within a
sector simultaneously via hot-hole assisted erase. The
data is programmed using hot electron injection.