FINAL
Am28F512
512 Kilobit (64 K x 8-Bit)
CMOS 12.0 Volt, Bulk Erase Flash Memory
DISTINCTIVE CHARACTERISTICS
s
High performance
— 70 ns maximum access time
s
CMOS Low power consumption
— 30 mA maximum active current
— 100 µA maximum standby current
— No data retention power consumption
s
Compatible with JEDEC-standard byte-wide
32-Pin EPROM pinouts
— 32-pin PDIP
— 32-pin PLCC
— 32-pin TSOP
s
10,000 write/erase cycles minimum
s
Write and erase voltage 12.0 V
±5%
s
Latch-up protected to 100 mA
from -1 V to V
CC
+1 V
s
Flasherase Electrical Bulk Chip-Erase
— One second typical chip-erase
s
Flashrite Programming
— 10 µs typical byte-program
— One second typical chip program
s
Command register architecture for
microprocessor/microcontroller compatible
write interface
s
On-chip address and data latches
s
Advanced CMOS flash memory technology
— Low cost single transistor memory cell
s
Automatic write/erase pulse stop timer
GENERAL DESCRIPTION
The Am28F512 is a 512 K bit Flash memory orga-
nized as 64 Kbytes of 8 bits each. AMD’s Flash mem-
ories offer the most cost-effective and reliable read/
write non-volatile random access memor y. The
Am28F512 is packaged in 32-pin PDIP, PLCC, and
TSOP versions. It is designed to be reprogrammed
and erased in-system or in standard EPROM pro-
grammers. The Am28F512 is erased when shipped
from the factory.
The standard Am28F512 offers access times as fast as
70 ns, allowing operation of high-speed microproces-
sors without wait states. To eliminate bus contention,
the Am28F512 has separate chip enable (CE#) and
output enable (OE#) controls.
AMD’s Flash memories augment EPROM functionality
with in-circuit electrical erasure and programming. The
Am28F512 uses a command register to manage this
functionality, while maintaining a standard JEDEC
Flash Standard 32-pin pinout. The command register
allows for 100% TTL level control inputs and fixed
power supply levels during erase and programming.
AMD’s Flash technology reliably stores memory con-
tents even after 10,000 erase and program cycles. The
AMD cell is designed to optimize the erase and pro-
Publication#
11561
Rev:
G
Amendment/+2
Issue Date:
January 1998
gramming mechanisms. In addition, the combination of
advanced tunnel oxide processing and low internal
electric fields for erase and programming operations
produces reliable cycling. The Am28F512 uses a
12.0 V ± 5% V
PP
high voltage input to perform the
Flasherase and Flashrite algorithms.
The highest degree of latch-up protection is achieved
with AMD’s proprietary non-epi process. Latch-up pro-
tection is provided for stresses up to 100 mA on ad-
dress and data pins from -1 V to V
CC
+1 V.
The Am28F512 is byte programmable using 10 ms pro-
gramming pulses in accordance with AMD’s Flashrite
programming algorithm. The typical room temperature
programming time of the Am28F512 is one second.
The entire chip is bulk erased using 10 ms erase pulses
according to AMD’s Flasherase algorithm. Typical era-
sure at room temperature is accomplished in less than
one second. The windowed package and the 15-20
minutes required for EPROM erasure using ultra-violet
light are eliminated.
Commands are written to the command register using
standard microprocessor write timings. Register con-
tents serve as inputs to an internal state-machine which
controls the erase and programming circuitry. During
write cycles, the command register internally latches
address and data needed for the programming and
erase operations. For system design simplification, the
Am28F512 is designed to support either WE# or CE#
controlled writes. During a system write cycle, ad-
dresses are latched on the falling edge of WE# or CE#
whichever occurs last. Data is latched on the rising edge
of WE# or CE# whichever occurs first. To simplify the fol-
lowing discussion, the WE# pin is used as the write cycle
control pin throughout the rest of this text. All setup and
hold times are with respect to the WE# signal.
AMD’s Flash technology combines years of EPROM
and EEPROM experience to produce the highest levels
of quality, reliability, and cost effectiveness. The
Am28F512 electrically erases all bits simultaneously
using Fowler-Nordheim tunneling. The bytes are pro-
grammed one byte at a time using the EPROM
programming mechanism of hot electron injection.
BLOCK DIAGRAM
DQ0–DQ7
V
CC
V
SS
V
PP
Erase
Voltage
Switch
State
Control
Command
Register
To Array
Input/Output
Buffers
WE#
Program
Voltage
Switch
CE#
OE#
Chip Enable
Output Enable
Logic
Data
Latch
Low V
CC
Detector
Program/Erase
Pulse Timer
A0–A15
Address
Latch
Y-Decoder
Y-Gating
X-Decoder
524,288
Bit
Cell Matrix
11561G-1
PRODUCT SELECTOR GUIDE
Family Part Number
Speed Options (V
CC
= 5.0 V
±
10%)
Max Access Time (ns)
CE# (E#) Access (ns)
OE# (G#) Access (ns)
-70
70
70
35
-90
90
90
35
Am28F512
-120
120
120
50
-150
150
150
55
-200
200
200
55
2
Am28F512
ORDERING INFORMATION
Standard Products
AMD standard products are available in several packages and operating ranges. The order number (Valid Combination) is formed
by a combination of:
AM28F512
-70
J
C
B
OPTIONAL PROCESSING
Blank = Standard Processing
B
= Burn-In
Contact an AMD representative for more information.
TEMPERATURE RANGE
C = Commercial (0°C to +70°C)
I = Industrial (–40°C to +85°C)
E = Extended (–55°C to +125°C)
PACKAGE TYPE
P = 32-Pin Plastic DIP (PD 032)
J = 32-Pin Rectangular Plastic Leaded Chip
Carrier (PL 032)
E = 32-Pin Thin Small Outline Package (TSOP)
Standard Pinout (TS 032)
F = 32-Pin Thin Small Outline Package (TSOP)
Reverse Pinout (TSR032)
SPEED OPTION
See Product Selector Guide and Valid Combinations
DEVICE NUMBER/DESCRIPTION
Am28F512
512 Kilobit (64 K x 8-Bit) CMOS Flash Memory
Valid Combinations
AM28F256-70
AM28F256-90
AM28F256-120
AM28F256-150
AM28F256-200
PC, PI, PE,
JC, JI, JE,
EC, EI, EE,
FC, FI, FE
Valid Combinations
Valid Combinations list configurations planned to be sup-
ported in volume for this device. Consult the local AMD sales
office to confirm availability of specific valid combinations and
to check on newly released combinations.
Am28F512
5
嵌入式系统
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
