PRELIMINARY
Am29F200A
2 Megabit (256 K x 8-Bit/128 K x 16-Bit)
CMOS 5.0 Volt-only, Boot Sector Flash Memory
DISTINCTIVE CHARACTERISTICS
s
5.0 V
±
10% for read and write operations
— Minimizes system level power requirements
s
High performance
— Access times as fast as 55 ns
s
Low power consumption
— 20 mA typical active read current (byte mode)
— 28 mA typical active read current for
(word mode)
— 30 mA typical program/erase current
— 1
µA
typical standby current
s
Sector erase architecture
— One 16 Kbyte, two 8 Kbyte, one 32 Kbyte, and
three 64 Kbyte sectors (byte mode)
— One 8 Kword, two 4 Kword, one 16 Kword, and
three 32 Kword sectors (word mode)
— 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/erase cycles guaranteed
s
Package options
— 44-pin SO
— 48-pin TSOP
s
Compatible with JEDEC standards
— Pinout and software compatible with
single-power-supply flash
— Superior inadvertent write protection
s
Data# Polling and Toggle Bit
— Detects program or erase cycle completion
s
Ready/Busy# output (RY/BY#)
— Hardware method for detection of program or
erase cycle completion
s
Erase Suspend/Erase Resume
— Supports reading data from a sector not being
erased
s
Hardware RESET# pin
— Resets internal state machine to the reading
array data
Publication#
20637
Rev:
B
Amendment/+3
Issue Date:
March 1998
P R E L I M I N A R Y
GENERAL DESCRIPTION
The Am29F200A is a 2 Mbit, 5.0 Volt-only Flash mem-
ory organized as 262,144 bytes or 131,072 words. The
8 bits of data appear on DQ0–DQ7; the 16 bits on DQ0–
DQ15. The Am29F200A is offered in 44-pin SO and
48-pin TSOP packages. This device is designed to be
programmed in-system with the standard system 5.0
volt V
CC
supply. A 12.0 volt V
PP
is not required for
program or erase operations. The device can also be
reprogrammed in standard EPROM programmers.
The standard device offers access times of 55, 70,
9 0, 12 0, an d 15 0 n s, allowin g op era tio n of
high-speed microprocessors 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 pro-
grammed) before executing the erase operation. Dur-
ing 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/
DQ2 (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 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 mem-
ory manufacturing experience to produce the highest lev-
els of quality, reliability and cost effectiveness. The device
electrically erases all bits within a sector simulta-
neously via Fowler-Nordheim tunneling. The data is
programmed using hot electron injection.
2
Am29F200A
stm32/stm8
京公网安备 11010802033920号
EEWORLD
