PRELIMINARY
Am29F002/Am29F002N
2 Megabit (256 K x 8-Bit)
CMOS 5.0 Volt-only Boot Sector Flash Memory
DISTINCTIVE CHARACTERISTICS
s
Single power supply operation
— 5.0 Volt-only operation for read, erase, and
program operations
— Minimizes system level requirements
s
High performance
— Access times as fast as 55 ns
s
Low power consumption (typical values at 5
MHz)
— 1 µA standby mode current
— 20 mA read current
— 30 mA program/erase current
s
Flexible sector architecture
— One 16 Kbyte, two 8 Kbyte, one 32 Kbyte, and
three 64 Kbyte sectors
— Supports full chip erase
— Sector Protection features:
A hardware method of locking a sector to
prevent any program or erase operations within
that sector
Sectors can be locked via programming
equipment
Temporary Sector Unprotect feature allows code
changes in previously locked sectors
s
Top or bottom boot block configurations
available
s
Embedded Algorithms
— Embedded Erase algorithm automatically
preprograms and erases the entire chip or any
combination of designated sectors
— Embedded Program algorithm automatically
writes and verifies data at specified addresses
s
Minimum 100,000 write cycle guarantee per
sector
s
Package option
— 32-pin PDIP
— 32-pin TSOP
— 32-pin PLCC
s
Compatibility with JEDEC standards
— Pinout and software compatible with single-
power supply Flash
— Superior inadvertent write protection
s
Data# Polling and toggle bits
— Provides a software method of detecting
program or erase operation completion
s
Erase Suspend/Erase Resume
— Suspends an erase operation to read data from,
or program data to, a sector that is not being
erased, then resumes the erase operation
s
Hardware reset pin (RESET#)
— Hardware method to reset the device to reading
array data (not available on Am29F002N)
Publication#
20818
Rev:
C
Amendment/+2
Issue Date:
March 1998
PRELIMINARY
GENERAL DESCRIPTION
The Am29F002 Family consists of 2 Mbit, 5.0 volt-only
Flash memory devices organized as 262,144 bytes.
The Am29F002 offers the RESET# function, the
Am29F002N does not. The data appears on DQ7–
DQ0. The device is offered in 32-pin PLCC, 32-pin
TSOP, and 32-pin PDIP packages. This device is
designed to be programmed in-system with the
standard system 5.0 volt V
CC
supply. No V
PP
is
required for write or erase operations. The device can
also be programmed in standard EPROM program-
mers.
The standard device offers access times of 55, 70, 90,
and 120 ns, allowing high speed microprocessors 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
standard microprocessor write timings. Register con-
tents serve as input to an internal state-machine that
controls 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
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 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
hardware RESET# pin
terminates any operation
in progress and resets the internal state machine to
reading array data. The RESET# pin may be tied to the
system reset circuitry. A system reset would thus also
reset the device, enabling the system microprocessor
to read the boot-up firmware from the Flash memory.
(This feature is not available on the Am29F002N.)
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 tun-
neling. The data is programmed using hot electron
injection.
2
Am29F002/Am29F002N
Microcontroller MCU
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