PRELIMINARY
Am29LV004
4 Megabit (512 K x 8-Bit)
CMOS 3.0 Volt-only Boot Sector Flash Memory
DISTINCTIVE CHARACTERISTICS
s
Single power supply operation
— Full voltage range: 2.7 to 3.6 volt read and write
operations for battery-powered applications
— Regulated voltage range: 3.0 to 3.6 volt read
and write operations and for compatibility with
high performance 3.3 volt microprocessors
s
High performance
— Full voltage range: access times as fast as 100
ns
— Regulated voltage range: access times as fast
as 90 ns
s
Ultra low power consumption (typical values at
5 MHz)
— 200 nA Automatic Sleep mode current
— 200 nA standby mode current
— 10 mA read current
— 20 mA program/erase current
s
Flexible sector architecture
— One 16 Kbyte, two 8 Kbyte, one 32 Kbyte, and
seven 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
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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
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Typical 1,000,000 write cycles per sector
(100,000 cycles minimum guaranteed)
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Package option
— 40-pin TSOP
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
Ready/Busy# pin (RY/BY#)
— Provides a hardware method of detecting
program or erase cycle 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
This document contains information on a product under development at Advanced Micro Devices. The information
is intended to help you evaluate this product. AMD reserves the right to change or discontinue work on this proposed
product without notice.
Publication#
20510
Rev:
D
Amendment/+1
Issue Date:
March 1998
Refer to AMD’s Website (www.amd.com) for the latest information.
P R E L I M I N A R Y
GENERAL DESCRIPTION
The Am29LV004 is an 4 Mbit, 3.0 volt-only Flash
memory organized as 524,288 bytes. The device is
offered in a 40-pin TSOP package. The byte-wide (x8)
data appears on DQ7–DQ0. This device requires only
a single, 3.0 volt V
CC
supply to perform read, program,
and erase operations. A standard EPROM pro-
grammer can also be used to program and erase the
device.
The standard device offers access times of 90, 100,
120, and 150 ns, allowing high speed microprocessors
to operate without wait states. To eliminate bus conten-
tion the device has separate chip enable (CE#), write
enable (WE#) and output enable (OE#) controls.
The device requires only a
single 3.0 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 command
sequence. This initiates the
Embedded Erase
algo-
rithm—an internal algorithm that automatically prepro-
grams 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 observing the RY/BY#
pin, or 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.
The device offers two power-saving features. When
addresses have been stable for a specified amount of
time, the device enters the
automatic sleep mode.
The system can also place the device into the
standby
mode.
Power consumption is greatly reduced in both
these modes.
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
Am29LV004
PCB Design
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