ETC AM29F004BT-55JI

Am29F004B
4 Megabit (512 K x 8-Bit)
CMOS 5.0 Volt-only Boot Sector Flash Memory
DISTINCTIVE CHARACTERISTICS
■ 5.0 Volt single power supply operation
— Minimizes system-level power requirements
■ High performance
— Access times as fast as 55 ns
■ Manufactured on 0.32 µm process technology
■ Ultra low power consumption (typical values at
5 MHz)
— 20 mA typical active read current
— 30 mA typical program/erase current
— 1 µA typical standby mode current
■ 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 in-system or via
programming equipment
Temporary Sector Unprotect feature allows code
changes in previously locked sectors
■ Top or bottom boot block configurations available
■ Minimum 1,000,000 write cycle guarantee per
sector
■ Package option
— 32-pin PLCC
■ Compatible with JEDEC standards
— Pinout and software compatible with singlepower supply Flash
— Superior inadvertent write protection
■ 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
■ 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
■ Data# Polling and toggle bits
— Provides a software method of detecting
program or erase operation completion
■ 20-year data retention at 125°C
This Data Sheet states AMD’s current technical specifications regarding the Products described herein. This Data
Sheet may be revised by subsequent versions or modifications due to changes in technical specifications.
Publication# 22286 Rev: E Amendment/0
Issue Date: November 29, 2000
GENERAL DESCRIPTION
The Am29F004B is a 4 Mbit, 5.0 volt-only Flash
memory device organized as 524,288 bytes. The data
appears on DQ0–DQ7. The device is offered in a 32pin PLCC package. This device is designed to be programmed in-system with the standard system 5.0 volt
VCC supply. A 12.0 volt VPP is not required for program or
erase operations. The device can also be programmed in
standard EPROM programmers.
The device offers access times of 55, 70, 90, and 120 ns,
allowing high speed microprocessors to operate
without wait states. To eliminate bus contention each
device has separate chip enable (CE#), write enable
(WE#) and output enable (OE#) controls.
Each device requires only a single 5.0 volt power
supply for both read and write functions. Internally
generated and regulated voltages are provided for the
program and erase operations.
The Am29F004B is entirely command set compatible
with the JEDEC single-power-supply Flash standard. Commands are written to the command register
using standard microprocessor write timing. Register
contents serve as inputs 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 automatically times the program pulse widths and verifies
proper cell margin.
Device erasure occurs by executing the erase
command sequence. This initiates the Embedded
2
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), or 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
VCC detector that automatically inhibits write operations
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 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 device offers a standby mode as a power-saving
feature. Once the system places the device into the
standby mode power consumption is greatly reduced.
AMD’s Flash technology combines years of Flash
memory manufacturing experience to produce the
highest levels of quality, reliability and cost effectiveness. The device electrically erases all bits within a
sector simultaneously via Fowler-Nordheim tunnelling.
The data is programmed using hot electron injection.
Am29F004B
TABLE OF CONTENTS
Product Selector Guide . . . . . . . . . . . . . . . . . . . . . 4
Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Connection Diagrams . . . . . . . . . . . . . . . . . . . . . . . 5
Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Logic Symbol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Ordering Information . . . . . . . . . . . . . . . . . . . . . . . 7
Device Bus Operations . . . . . . . . . . . . . . . . . . . . . . 8
Table 1. Am29F004B Device Bus Operations ..................................8
Requirements for Reading Array Data ..................................... 8
Writing Commands/Command Sequences .............................. 8
Program and Erase Operation Status ...................................... 8
Standby Mode .......................................................................... 8
Output Disable Mode ................................................................ 9
Table 2. Am29F004B Top Boot Block Sector Addresses .................9
Table 3. Am29F004B Bottom Boot Block Sector Addresses ............9
Autoselect Mode ..................................................................... 10
Table 4. Am29F004B Autoselect Codes (High Voltage Method) ....10
Sector Protection/Unprotection ............................................... 10
DQ5: Exceeded Timing Limits ................................................ 20
DQ3: Sector Erase Timer ....................................................... 21
Figure 6. Toggle Bit Algorithm ........................................................ 21
Table 6. Write Operation Status ..................................................... 22
Absolute Maximum Ratings . . . . . . . . . . . . . . . . 23
Figure 7. Maximum Negative Overshoot Waveform ...................... 23
Figure 8. Maximum Positive Overshoot Waveform ........................ 23
Operating Ranges . . . . . . . . . . . . . . . . . . . . . . . . . 23
DC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . 24
TTL/NMOS Compatible .......................................................... 24
CMOS Compatible .................................................................. 25
Test Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Figure 9. Test Setup ....................................................................... 26
Table 7. Test Specifications ........................................................... 26
Key to Switching Waveforms. . . . . . . . . . . . . . . . 26
AC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . 27
Read Operations .................................................................... 27
Figure 10. Read Operations Timings ............................................. 27
Figure 1. In-System Sector Protect/Sector Unprotect Algorithms ...11
Erase/Program Operations ..................................................... 28
Temporary Sector Unprotect .................................................. 12
Figure 11. Program Operation Timings .......................................... 29
Figure 12. Chip/Sector Erase Operation Timings .......................... 29
Figure 13. Data# Polling Timings (During Embedded Algorithms) . 30
Figure 14. Toggle Bit Timings (During Embedded Algorithms) ...... 30
Figure 15. DQ2 vs. DQ6 ................................................................. 30
Figure 16. Sector Unlock Sequence Timing Diagram .................... 31
Figure 17. Sector Relock Timing Diagram ..................................... 31
Figure 18. Sector Protect/Unprotect Timing Diagram .................... 32
Figure 2. Temporary Sector Unprotect Operation ...........................12
Hardware Data Protection ...................................................... 13
Low VCC Write Inhibit ......................................................................13
Write Pulse “Glitch” Protection ........................................................13
Logical Inhibit ..................................................................................13
Power-Up Write Inhibit ....................................................................13
Command Definitions . . . . . . . . . . . . . . . . . . . . . . 14
Reading Array Data ................................................................ 14
Reset Command ..................................................................... 14
Autoselect Command Sequence ............................................ 14
Byte Program Command Sequence ....................................... 14
Figure 3. Program Operation ..........................................................15
Chip Erase Command Sequence ........................................... 15
Sector Erase Command Sequence ........................................ 15
Figure 4. Erase Operation ...............................................................16
Erase Suspend/Erase Resume Commands ........................... 17
Command Definitions ............................................................. 18
Table 5. Am29F004B Command Definitions ...................................18
Write Operation Status . . . . . . . . . . . . . . . . . . . . . 19
DQ7: Data# Polling ................................................................. 19
Figure 5. Data# Polling Algorithm ...................................................19
DQ6: Toggle Bit I .................................................................... 20
DQ2: Toggle Bit II ................................................................... 20
Reading Toggle Bits DQ6/DQ2 .............................................. 20
Alternate CE# Controlled Erase/Program Operations ............ 33
Figure 19. Alternate CE# Controlled Write Operation Timings ...... 34
Erase and Programming Performance . . . . . . . 35
Latchup Characteristics . . . . . . . . . . . . . . . . . . . . 35
PLCC Pin Capacitance . . . . . . . . . . . . . . . . . . . . . 35
Data Retention. . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Physical Dimensions . . . . . . . . . . . . . . . . . . . . . . 36
PL 032—32-Pin Plastic Leaded Chip Carrier ......................... 36
Revision Summary . . . . . . . . . . . . . . . . . . . . . . . . 37
Revision A (January 1999) ..................................................... 37
Revision B (March 10, 1999) .................................................. 37
Revision B+1 (March 18, 1999) .............................................. 37
Revision B+2 (May 14, 1999) ................................................. 37
Revision B+3 (July 12, 1999) .................................................. 37
Revision C (November 12, 1999) ........................................... 37
Revision D (February 22, 2000) .............................................. 37
Revision E (November 29, 2000) ............................................ 37
Am29F004B
3
PRODUCT SELECTOR GUIDE
Family Part Number
Speed Option
Am29F004B
VCC = 5.0 V ± 5%
-55
VCC = 5.0 V ± 10%
-70
-90
-120
Max access time, ns (tACC)
55
70
90
120
Max CE# access time, ns (tCE)
55
70
90
120
Max OE# access time, ns (tOE)
25
30
35
45
Note: See “AC Characteristics” for full specifications.
BLOCK DIAGRAM
DQ0–DQ7
VCC
Sector Switches
VSS
Erase Voltage
Generator
WE#
Input/Output
Buffers
State
Control
Command
Register
PGM Voltage
Generator
Chip Enable
Output Enable
Logic
CE#
OE#
VCC Detector
Address Latch
STB
Timer
A0–A18
4
Am29F004B
STB
Data
Latch
Y-Decoder
Y-Gating
X-Decoder
Cell Matrix
4 3 2
WE#
A17
A18
VCC
A16
A12
A15
CONNECTION DIAGRAMS
1 32 31 30
A7
5
29
A14
A6
6
28
A13
A5
A4
7
27
A8
8
26
A9
A3
9
25
A11
A2
10
24
OE#
A1
11
23
A10
A0
12
22
DQ0
13
21
CE#
DQ7
PLCC
DQ5
DQ6
DQ4
VSS
DQ3
DQ1
DQ2
14 15 16 17 18 19 20
Am29F004B
5
PIN CONFIGURATION
A0–A18
LOGIC SYMBOL
= 19 addresses
19
DQ0–DQ7 = 8 data inputs/outputs
A0–A18
CE#
= Chip enable
OE#
= Output enable
WE#
= Write enable
CE#
VCC
= +5.0 V single power supply
(see Product Selector Guide for
device speed ratings and voltage
supply tolerances)
OE#
VSS
= Device ground
NC
= Pin not connected internally
6
8
DQ0–DQ7
WE#
Am29F004B
ORDERING INFORMATION
Standard Product
AMD standard products are available in several packages and operating ranges. The order number (Valid Combination) is formed by a combination of the elements below.
Am29F004B
T
-55
J
I
TEMPERATURE RANGE
I
= Industrial (–40°C to +85°C)
E
= Extended (–55°C to +125°C)
PACKAGE TYPE
J
= 32-Pin Rectangular Plastic Leaded Chip Carrier (PL 032)
SPEED OPTION
See Product Selector Guide and Valid Combinations
BOOT CODE SECTOR ARCHITECTURE
T
=
Top sector
B
=
Bottom sector
DEVICE NUMBER/DESCRIPTION
Am29F004B
4 Megabit (512 K x 8-Bit) CMOS Flash Memory
5.0 Volt-only Program and Erase
Valid Combinations
Valid Combinations
VCC Voltage
AM29F004BT-55
AM29F004BB-55
5.0 V ± 5%
JI
AM29F004BT-70
AM29F004BB-70
AM29F004BT-90
AM29F004BB-90
Valid Combinations list configurations planned to be supported 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.
5.0 V ± 10%
JI, JE
AM29F004BT-120
AM29F004BB-120
Am29F004B
7
DEVICE BUS OPERATIONS
This section describes the requirements and use of the
device bus operations, which are initiated through the
internal command register. The command register
itself does not occupy any addressable memory location. The register is composed of latches that store the
commands, along with the address and data information needed to execute the command. The contents of
Table 1.
the register serve as inputs to the internal state
machine. The state machine outputs dictate the function of the device. The appropriate device bus
operations table lists the inputs and control levels
required, and the resulting output. The following subsections describe each of these operations in further
detail.
Am29F004B Device Bus Operations
Operation
CE#
OE#
WE#
A0–A18
DQ0–DQ7
DOUT
Read
L
L
H
AIN
Write
L
H
L
AIN
DIN
VCC ± 0.5 V
X
X
X
High-Z
CMOS Standby
TTL Standby
H
X
X
X
High-Z
Output Disable
L
H
H
X
High-Z
Temporary Sector Unprotect (See Note)
X
X
X
X
X
Legend:
L = Logic Low = VIL, H = Logic High = VIH, VID = 12.0 ± 0.5 V, X = Don’t Care, DIN = Data In, DOUT = Data Out, AIN = Address In
Note: See the sections on Sector Protection and Temporary Sector Unprotect for more information.
Requirements for Reading Array Data
To read array data from the outputs, the system must
drive the CE# and OE# pins to VIL. CE# is the power
control and selects the device. OE# is the output
control and gates array data to the output pins. WE#
should remain at VIH.
The internal state machine is set for reading array data
upon device power-up. This ensures that no spurious
alteration of the memory content occurs during the
power transition. No command is necessary in this
mode to obtain array data. Standard microprocessor
read cycles that assert valid addresses on the device
address inputs produce valid data on the device data
outputs. The device remains enabled for read access
until the command register contents are altered.
See “Reading Array Data” for more information. Refer
to the AC Read Operations table for timing specifications and to the Read Operations Timings diagram for
the timing waveforms. ICC1 in the DC Characteristics
table represents the active current specification for
reading array data.
Writing Commands/Command Sequences
To write a command or command sequence (which
includes programming data to the device and erasing
sectors of memory), the system must drive WE# and
CE# to VIL, and OE# to VIH.
An erase operation can erase one sector, multiple sectors, or the entire device. The Sector Address Tables
indicate the address space that each sector occupies.
8
A “sector address” consists of the address bits required
to uniquely select a sector. See the Command Definitions section for details on erasing a sector or the entire
chip, or suspending/resuming the erase operation.
After the system writes the autoselect command
sequence, the device enters the autoselect mode. The
system can then read autoselect codes from the
internal register (which is separate from the memory
array) on DQ7–DQ0. Standard read cycle timings apply
in this mode. Refer to the “Autoselect Mode” and
Autoselect Command Sequence sections for more
information.
ICC2 in the DC Characteristics table represents the
active current specification for the write mode. The “AC
Characteristics” section contains timing specification
tables and timing diagrams for write operations.
Program and Erase Operation Status
During an erase or program operation, the system may
check the status of the operation by reading the status
bits on DQ7–DQ0. Standard read cycle timings and ICC
read specifications apply. Refer to “Write Operation
Status” for more information, and to each AC Characteristics section for timing diagrams.
Standby Mode
When the system is not reading or writing to the device,
it can place the device in the standby mode. In this
mode, current consumption is greatly reduced, and the
Am29F004B
outputs are placed in the high impedance state, independent of the OE# input.
The device enters the CMOS standby mode when CE#
pin is held at VCC ± 0.5 V. (Note that this is a more
restricted voltage range than VIH.) The device enters
the TTL standby mode when CE# pin is held at VIH .
The device requires standard access time (tCE) for read
access when the device is in either of these standby
modes, before it is ready to read data.
Table 2.
If the device is deselected during erasure or programming, the device draws active current until the
operation is completed.
In the DC Characteristics tables, ICC3 represents the
standby current specification.
Output Disable Mode
When the OE# input is at VIH, output from the device is
disabled. The output pins are placed in the high impedance state.
Am29F004B Top Boot Block Sector Addresses
Sector
A18
A17
A16
A15
A14
A13
Sector Size
(Kbytes)
Address Range
(in hexadecimal)
SA0
0
0
0
X
X
X
64
00000h–0FFFFh
SA1
0
0
1
X
X
X
64
10000h–1FFFFh
SA2
0
1
0
X
X
X
64
20000h–2FFFFh
SA3
0
1
1
X
X
X
64
30000h–3FFFFh
SA4
1
0
0
X
X
X
64
40000h–4FFFFh
SA5
1
0
1
X
X
X
64
50000h–5FFFFh
SA6
1
1
0
X
X
X
64
60000h–6FFFFh
SA7
1
1
1
0
X
X
32
70000h–77FFFh
SA8
1
1
1
1
0
0
8
78000h–79FFFh
SA9
1
1
1
1
0
1
8
7A000h–7BFFFh
SA10
1
1
1
1
1
X
16
7C000h–7FFFFh
Table 3.
Am29F004B Bottom Boot Block Sector Addresses
Sector
A18
A17
A16
A15
A14
A13
Sector Size
(Kbytes)
Address Range
(in hexadecimal)
SA0
0
0
0
0
0
X
16
00000h–03FFFh
SA1
0
0
0
0
1
0
8
04000h–05FFFh
SA2
0
0
0
0
1
1
8
06000h–07FFFh
SA3
0
0
0
1
X
X
32
08000h–0FFFFh
SA4
0
0
1
X
X
X
64
10000h–1FFFFh
SA5
0
1
0
X
X
X
64
20000h–2FFFFh
SA6
0
1
1
X
X
X
64
30000h–3FFFFh
SA7
1
0
0
X
X
X
64
40000h–4FFFFh
SA8
1
0
1
X
X
0
64
50000h–5FFFFh
SA9
1
1
0
X
X
1
64
60000h–6FFFFh
SA10
1
1
1
X
X
X
64
70000h–7FFFFh
Am29F004B
9
Autoselect Mode
The autoselect mode provides manufacturer and
device identification, and sector protection verification,
through identifier codes output on DQ7–DQ0. This
mode is primarily intended for programming equipment
to automatically match a device to be programmed with
its corresponding programming algorithm. However,
the autoselect codes can also be accessed in-system
through the command register.
When using programming equipment, the autoselect
mode requires VID on address pin A9. Address pins A6,
A1, and A0 must be as shown in Autoselect Codes
(High Voltage Method) table. In addition, when verifying
Table 4.
sector protection, the sector address must appear on
the appropriate highest order address bits. Refer to the
corresponding Sector Address Tables. The Command
Definitions table shows the remaining address bits that
are don’t care. When all necessary bits have been set
as required, the programming equipment may then
read the corresponding identifier code on DQ7–DQ0.
To access the autoselect codes in-system, the host
system can issue the autoselect command via the
command register, as shown in the Command Definitions table. This method does not require VID. See
“Command Definitions” for details on using the autoselect mode.
Am29F004B Autoselect Codes (High Voltage Method)
CE#
OE#
WE#
A18
to
A13
Manufacturer ID: AMD
L
L
H
X
X
VID
X
L
X
L
L
01h
Device ID:
Am29F004B (Top Boot Block)
L
L
H
X
X
L
X
L
H
77h
L
H
VID
X
L
Device ID:
Am29F004B (Bottom Boot Block)
L
L
H
X
X
L
X
L
H
7Bh
L
H
VID
X
L
Description
A12
to
A10
A9
A8
to
A7
A6
A5
to
A2
A1
A0
DQ7
to
DQ0
01h
(protected)
Sector Protection Verification
L
L
H
SA
X
VID
X
L
X
H
L
00h
(unprotected)
L = Logic Low = VIL, H = Logic High = VIH, SA = Sector Address, X = Don’t care.
Sector Protection/Unprotection
The hardware sector protection feature disables both
program and erase operations in any sector. The hardware sector unprotection feature re-enables both
program and erase operations in previously protected
sectors.
The primary method requires VID on the OE# pin only,
and can be implemented either in-system or via programming equipment. Figures 1 and 2 show the
algorithms and Figures 16, 17, and 18 show the timing
diagrams. This method uses standard microprocessor
bus cycle timing in addition to the sector unlock and
sector relock sequences. For sector unprotect, all
unprotected sectors must first be protected prior to the
first sector unprotect write cycle.
10
The alternate method intended only for programming
equipment required VID on address pin A9 and OE#.
This method is compatible with programmer routines
written for earlier 5.0 volt-only AMD Flash devices.
Publication number 22289 contains further details;
contact an AMD representative to request a copy.
The device is shipped with all sectors unprotected.
AMD offers the option of programming and protecting
sectors at its factory prior to shipping the device
through AMD’s ExpressFlash™ Service. Contact an
AMD representative for details.
It is possible to determine whether a sector is protected
or unprotected. See “Autoselect Mode” for details.
Am29F004B
START
START
PLSCNT = 1
PLSCNT = 1
Set OE# = VID.
Write Sector
Unlock sequence
with command 24h
Set OE# = VID.
Write Sector
Unlock sequence
with command 24h
Protect all sectors:
The indicated portion
of the sector protect
algorithm must be
performed for all
unprotected sectors
prior to issuing the
first sector
unprotect address
Wait 1 µs
Write 60h to any
address with
A6 = 0, A5 = 1,
A1 = 1, A0 = 0
Set up sector
address
Wait 1 µs
Write 60h to
any address with
A6 = 1, A5 = 1,
A1 = 1, A0 = 0
No
All sectors
protected?
Sector Protect:
Write 60h to sector
address with
A6 = 0, A5 = 1,
A1 = 1, A0 = 0
Yes
Set up first sector
address
Wait 150 ± 15 µs
Sector Unprotect:
Write 60h to sector
address with
A6 = 1, A5 = 1,
A1 = 1, A0 = 0
Set OE# = VIH
Increment
PLSCNT
Verify Sector
Protect: Write 40h
to sector address
with A6 = 0,
A1 = 1, A0 = 0
Yes
Device failed
Wait 15 ± 1.5 ms
Set OE# = VIL
Read from
sector address
with A6 = 0,
A1 = 1, A0 = 0
(requires 1 µs
access time)
No
PLSCNT
= 25?
Set OE# = VIH
Reset
PLSCNT = 1
Verify Sector
Unprotect: Write
40h to sector
address with
A6 = 1, A1 = 1,
A0 = 0
Increment
PLSCNT
Set OE# = VIL
Read from
sector address
with A6 = 1,
A1 = 1, A0 = 0
(requires 1 µs
access time)
No
Data = 01h?
Yes
No
Protect another
sector?
Yes
PLSCNT
= 1000?
No
Yes
Set OE# = VID.
Write Sector
Relock sequence.
Set OE# = VIH.
Device failed
Set up
next sector
address
No
Data = 00h?
Yes
Last sector
verified?
No
Yes
Sector Protect
Algorithm
Sector Protect
complete
Sector Unprotect
Algorithm
Set OE# = VID.
Write Sector
Relock sequence.
Set OE# = VIH.
Sector Unprotect
complete
Figure 1.
In-System Sector Protect/Sector Unprotect Algorithms
Am29F004B
11
Temporary Sector Unprotect
This feature allows temporary unprotection of previously protected sectors to change data in-system. The
Sector Unprotect mode is activated by setting the OE#
pin to 12.0 Volts (VID). Figure 2 shows the algorithm,
and Figures 16 and 17 show the timing diagrams, for
this feature. While OE# is at V ID, the sector unlock
sequence is written to the device. After the sector
unlock sequence is written, the OE# pin is taken back
to V IH . The device is now in the temporary sector
unprotect mode.
START
OE# = VID
Write the three-cycle
Unlock sequence with
command 20h (Figure 16)
While in this mode, formerly protected sectors can be
programmed or erased by selecting the appropriate
sector address during programming or erase operations. Either sector erase or chip erase operations can
be performed in this mode. Byte program operations
require only two cycles, while sector and chip erase
operations only require four cycles. Refer to the
Command Definitions table.
OE# = VIH (Note 1)
Perform Erase or
Program Operations
OE# = VID
Exiting the temporary sector unprotect mode is accomplished by either removing VCC from the device or by
taking OE# back to VID and writing the sector relock
sequence.
Write the two-cycle
Sector Relock sequence
(Figure 17)
After writing the sector relock sequence, the OE# pin is
taken back to VIH and all previously protected sectors
will be protected again.
OE# = VIH
Temporary Sector
Unprotect
Completed (Note 2)
Notes:
1. All protected sectors unprotected.
2. All previously protected sectors are protected once
again.
Figure 2.
12
Am29F004B
Temporary Sector Unprotect Operation
Hardware Data Protection
The command sequence requirement of unlock cycles
for programming or erasing provides data protection
against inadvertent writes (refer to the Command Definitions table). In addition, the following hardware data
protection measures prevent accidental erasure or programming, which might otherwise be caused by
spurious system level signals during VCC power-up and
power-down transitions, or from system noise.
Low VCC Write Inhibit
When V CC is less than V LKO, the device does not
accept any write cycles. This protects data during VCC
power-up and power-down. The command register and
all internal program/erase circuits are disabled, and the
device resets. Subsequent writes are ignored until VCC
is greater than V LKO. The system must provide the
proper signals to the control pins to prevent unintentional writes when VCC is greater than VLKO.
Write Pulse “Glitch” Protection
Noise pulses of less than 5 ns (typical) on OE#, CE# or
WE# do not initiate a write cycle.
Logical Inhibit
Write cycles are inhibited by holding any one of OE# =
VIL, CE# = VIH or WE# = VIH. To initiate a write cycle,
CE# and WE# must be a logical zero while OE# is a
logical one.
Power-Up Write Inhibit
If WE# = CE# = VIL and OE# = VIH during power up, the
device does not accept commands on the rising edge
of WE#. The internal state machine is automatically
reset to reading array data on power-up.
Am29F004B
13
COMMAND DEFINITIONS
Writing specific address and data commands or
sequences into the command register initiates device
operations. The Command Definitions table defines the
valid register command sequences. Writing incorrect
address and data values or writing them in the
improper sequence resets the device to reading array
data.
All addresses are latched on the falling edge of WE# or
CE#, whichever happens later. All data is latched on
the rising edge of WE# or CE#, whichever happens
first. Refer to the appropriate timing diagrams in the
“AC Characteristics” section.
Reading Array Data
The reset command may be written between the
sequence cycles in an autoselect command sequence.
Once in the autoselect mode, the reset command must
be written to return to reading array data (also applies
to autoselect during Erase Suspend).
If DQ5 goes high during a program or erase operation,
writing the reset command returns the device to
reading array data (also applies dur ing Erase
Suspend).
Autoselect Command Sequence
The device is automatically set to reading array data
after device power-up. No commands are required to
retrieve data. The device is also ready to read array
data after completing an Embedded Program or
Embedded Erase algorithm.
After the device accepts an Erase Suspend command,
the device enters the Erase Suspend mode. The
system can read array data using the standard read
timings, except that if it reads at an address within
erase-suspended sectors, the device outputs status
data. After completing a programming operation in the
Erase Suspend mode, the system may once again
read array data with the same exception. See “Erase
Suspend/Erase Resume Commands” for more information on this mode.
The system must issue the reset command to reenable the device for reading array data if DQ5 goes
high, or while in the autoselect mode. See the “Reset
Command” section, next.
See also “Requirements for Reading Array Data” in the
“Device Bus Operations” section for more information.
The Read Operations table provides the read parameters, and Read Operation Timings diagram shows the
timing diagram.
Reset Command
Writing the reset command to the device resets the
device to reading array data. Address bits are don’t
care for this command.
The reset command may be written between the
sequence cycles in an erase command sequence
before erasing begins. This resets the device to reading
array data. Once erasure begins, however, the device
ignores reset commands until the operation is
complete.
The reset command may be written between the
sequence cycles in a program command sequence
before programming begins. This resets the device to
reading array data (also applies to programming in
14
Erase Suspend mode). Once programming begins,
however, the device ignores reset commands until the
operation is complete.
The autoselect command sequence allows the host
system to access the manufacturer and devices codes,
and determine whether or not a sector is protected.
The Command Definitions table shows the address
and data requirements. This method is an alternative to
that shown in the Autoselect Codes (High Voltage
Method) table, which is intended for PROM programmers and requires VID on address bit A9.
The autoselect command sequence is initiated by
writing two unlock cycles, followed by the autoselect
command. The device then enters the autoselect
mode, and the system may read at any address any
number of times, without initiating another command
sequence.
A read cycle at address XX00h or retrieves the manufacturer code. A read cycle at address XX01h returns
the device code. A read cycle containing a sector
address (SA) and the address 02h in returns 01h if that
sector is protected, or 00h if it is unprotected. Refer to
the Sector Address tables for valid sector addresses.
The system must write the reset command to exit the
autoselect mode and return to reading array data.
Byte Program Command Sequence
Programming is a four-bus-cycle operation. The
program command sequence is initiated by writing two
unlock write cycles, followed by the program set-up
command. The program address and data are written
next, which in turn initiate the Embedded Program
algorithm. The system is not required to provide further
controls or timings. The device automatically provides
internally generated program pulses and verify the programmed cell margin. (Note that if the device is in the
temporary sector unprotect mode, the byte program
command sequence only requires two cycles.) The
Command Definitions table shows the address and
data requirements for the byte program command
sequence.
Am29F004B
When the Embedded Program algorithm is complete,
the device then returns to reading array data and
addresses are no longer latched. The system can
determine the status of the program operation by using
DQ7 or DQ6. See “Write Operation Status” for information on these status bits.
Any commands written to the device during the
Embedded Program Algorithm are ignored. The Sector
Erase command sequence should be reinitiated once
the device has returned to reading array data, to
ensure data integrity.
Programming is allowed in any sequence and across
sector boundaries. A bit cannot be programmed
from a “0” back to a “1”. Attempting to do so may halt
the operation and set DQ5 to “1”, or cause the Data#
Polling algorithm to indicate the operation was successful. However, a succeeding read will show that the
data is still “0”. Only erase operations can convert a “0”
to a “1”.
START
Sector Erase Command Sequence
No
Yes
No
Last Address?
Yes
Programming
Completed
Note: See the appropriate Command Definitions table for
program command sequence.
Figure 3.
Any com mand s wr i tten to th e chip d ur ing th e
Embedded Erase algorithm are ignored. The Sector
Erase command sequence should be reinitiated once
the device has returned to reading array data, to
ensure data integrity.
Figure 4 illustrates the algorithm for the erase operation. See the Erase/Program Operations tables in “AC
Characteristics” for parameters, and to the Chip/Sector
Erase Operation Timings for timing waveforms.
Data Poll
from System
Verify Data?
Increment Address
Chip erase is a six-bus-cycle operation. The chip erase
command sequence is initiated by writing two unlock
cycles, followed by a set-up command. Two additional
unlock write cycles are then followed by the chip erase
command, which in turn invokes the Embedded Erase
algorithm. The device does not require the system to
preprogram prior to erase. The Embedded Erase algorithm automatically preprograms and verifies the entire
memory for an all zero data pattern prior to electrical
erase. The system is not required to provide any controls or timings during these operations. (Note that if the
device is in the temporary sector unprotect mode, the
chip erase command sequence only requires four
cycles.) The Command Definitions table shows the
address and data requirements for the chip erase
command sequence.
The system can determine the status of the erase operation by using DQ7, DQ6, or DQ2. See “Write
Operation Status” for information on these status bits.
When the Embedded Erase algorithm is complete, the
device returns to reading array data and addresses are
no longer latched.
Write Program
Command Sequence
Embedded
Program
algorithm
in progress
Chip Erase Command Sequence
Program Operation
Sector erase is a six-bus-cycle operation. The sector
erase command sequence is initiated by writing two
unlock cycles, followed by a set-up command. Two
additional unlock write cycles are then followed by the
address of the sector to be erased, and the sector
erase command. (Note that if the device is in the temporar y sector unprotect mode, the sector erase
command sequence only requires four cycles.) The
Command Definitions table shows the address and
data requirements for the sector erase command
sequence.
The device does not require the system to preprogram
the memory prior to erase. The Embedded Erase algorithm automatically programs and verifies the sector for
an all zero data pattern prior to electrical erase. The
system is not required to provide any controls or
timings during these operations.
After the command sequence is written, a sector erase
time-out of 50 µs begins. During the time-out period,
additional sector addresses and sector erase com-
Am29F004B
15
mands may be written. Loading the sector erase buffer
may be done in any sequence, and the number of
sectors may be from one sector to all sectors. The time
between these additional cycles must be less than 50
µs, otherwise the last address and command might not
be accepted, and erasure may begin. It is recommended that processor interrupts be disabled during
this time to ensure all commands are accepted. The
interrupts can be re-enabled after the last Sector Erase
command is written. If the time between additional
sector erase commands can be assumed to be less
than 50 µs, the system need not monitor DQ3. Any
command other than Sector Erase or Erase
Suspend during the time-out period resets the
device to reading array data. The system must
rewrite the command sequence and any additional
sector addresses and commands.
the “AC Characteristics” section for parameters, and to
the Sector Erase Operations Timing diagram for timing
waveforms.
START
Write Erase
Command Sequence
Data Poll
from System
The system can monitor DQ3 to determine if the sector
erase timer has timed out. (See the “DQ3: Sector Erase
Timer” section.) The time-out begins from the rising
edge of the final WE# pulse in the command sequence.
No
Once the sector erase operation has begun, only the
Erase Suspend command is valid. All other commands
are ignored. The Sector Erase command sequence
should be reinitiated once the device has returned to
reading array data, to ensure data integrity.
When the Embedded Erase algorithm is complete, the
device returns to reading array data and addresses are
no longer latched. The system can determine the
status of the erase operation by using DQ7, DQ6, or
DQ2. Refer to “Write Operation Status” for information
on these status bits.
Data = FFh?
Yes
Erasure Completed
Notes:
1. See the appropriate Command Definitions table for erase
command sequence.
2. See “DQ3: Sector Erase Timer” for more information.
Figure 4 illustrates the algorithm for the erase operation. Refer to the Erase/Program Operations tables in
16
Embedded
Erase
algorithm
in progress
Am29F004B
Figure 4.
Erase Operation
Erase Suspend/Erase Resume Commands
The Erase Suspend command allows the system to
interrupt a sector erase operation and then read data
from, or program data to, any sector not selected for
erasure. This command is valid only during the sector
erase operation, including the 50 µs time-out period
during the sector erase command sequence. The
Erase Suspend command is ignored if written during
the chip erase operation or Embedded Program algorithm. Writing the Erase Suspend command during the
Sector Erase time-out immediately terminates the
time-out period and suspends the erase operation.
Addresses are “don’t-cares” when writing the Erase
Suspend command.
When the Erase Suspend command is written during a
sector erase operation, the device requires a maximum
of 20 µs to suspend the erase operation. However,
when the Erase Suspend command is written during
the sector erase time-out, the device immediately terminates the time-out period and suspends the erase
operation.
After the erase operation has been suspended, the
system can read array data from or program data to
any sector not selected for erasure. (The device “erase
suspends” all sectors selected for erasure.) Normal
read and write timings and command definitions apply.
Reading at any address within erase-suspended
sectors produces status data on DQ7–DQ0. The
system can use DQ7, or DQ6 and DQ2 together, to
determine if a sector is actively erasing or is erase-suspended. See “Write Operation Status” for information
on these status bits.
After an erase-suspended program operation is complete, the system can once again read array data within
non-suspended sectors. The system can determine
the status of the program operation using the DQ7 or
DQ6 status bits, just as in the standard program opera tio n. See “Wr ite Operation S tatus” for m ore
information.
The system may also write the autoselect command
sequence when the device is in the Erase Suspend
mode. The device allows reading autoselect codes
even at addresses within erasing sectors, since the
codes are not stored in the memory array. When the
device exits the autoselect mode, the device reverts to
the Erase Suspend mode, and is ready for another
valid operation. See “Autoselect Command Sequence”
for more information.
The system must write the Erase Resume command
(address bits are “don’t care”) to exit the erase suspend
mode and continue the sector erase operation. Further
writes of the Resume command are ignored. Another
Erase Suspend command can be written after the
device has resumed erasing.
Am29F004B
17
Command Definitions
Command
Sequence
(Note 1)
Cycles
Table 5.
Am29F004B Command Definitions
Bus Cycles (Notes 2–4)
First
Second
Addr
Data
RD
Third
Addr
Data
Addr
Fourth
Data Addr
Data
Fifth
Sixth
Addr Data
Addr
Data
Read (Note 5)
1
RA
Reset (Note 6)
1
XXX
F0
Manufacturer ID
4
555
AA
2AA
55
555
90
X00
01
Device ID,
Top Boot Block
4
555
AA
2AA
55
555
90
X01
77
Device ID,
Bottom Boot Block
4
555
AA
2AA
55
555
90
X01
7B
Sector Protect Verify
(Note 8)
4
555
AA
2AA
55
555
90
(SA)
X02
00
Program
4
555
AA
2AA
55
555
A0
PA
PD
Chip Erase
6
555
AA
2AA
55
555
80
555
AA
2AA
55
555
10
Sector Erase
6
555
AA
2AA
55
555
80
555
AA
2AA
55
SA
30
Erase Suspend (Note 11)
1
XXX
B0
Erase Resume (Note 12)
1
XXX
30
Temporary
Sector
Unprotect
Mode
(Note 9)
Enter TSU Mode
3
555
AA
2AA
55
555
20
Program
2
XXX
A0
PA
PD
SA+
60
SA+
40
Autoselect
(Note 7)
01
Sector Erase
4
XXX
80
XXX
AA
XXX
55
SA
30
Chip Erase
4
XXX
80
XXX
AA
XXX
55
555
10
Sector Unlock (Note 9)
3
555
AA
2AA
55
555
24
SA+
60
Sector Relock (Notes 9, 10)
2
XXX
90
XXX
00
Legend:
X = Don’t care
PD = Data to be programmed at location PA. Data latches on the
rising edge of WE# or CE# pulse, whichever happens first.
RA = Address of the memory location to be read.
SA = Address of the sector to be verified (in autoselect mode) or
erased. Address bits A18–A13 uniquely select any sector.
RD = Data read from location RA during read operation.
PA = Address of the memory location to be programmed.
Addresses latch on the falling edge of the WE# or CE# pulse,
whichever happens later.
Notes:
1. See Table 1 for description of bus operations.
2. All values are in hexadecimal.
3. Except when reading array or autoselect data, all bus cycles
are write operations.
SA+ = The sector address must be asserted in combination with
A0 = 0, A1 = 1, A5 = 1, and A6 = 0 (for protect) or 1 (for
unprotect).
8. The data is 00h for an unprotected sector and 01h for a
protected sector. See “Autoselect Command Sequence” for
more information.
9. To activate the sequence, OE# must be at VID.
4. Address bits A18–A11 are don’t cares for unlock and
command cycles, except when PA or SA is required.
10. The sector relock command in the second cycle may be
written as either 00h or F0h.
5. No unlock or command cycles required when reading array
data.
11. The system may read and program in non-erasing sectors, or
enter the autoselect mode, when in the Erase Suspend
mode. The Erase Suspend command is valid only during a
sector erase operation.
6. The Reset command is required to return to reading array
data when device is in the autoselect mode, or if DQ5 goes
high (while the device is providing status data).
7. The fourth cycle of the autoselect command sequence is a
read cycle.
18
12. The Erase Resume command is valid only during the Erase
Suspend mode.
Am29F004B
WRITE OPERATION STATUS
The device provides several bits to determine the
status of a write operation: DQ2, DQ3, DQ5, DQ6, and
DQ7. Table 6 and the following subsections describe
the functions of these bits. DQ7 and DQ6 each offer a
method for determining whether a program or erase
operation is complete or in progress. These three bits
are discussed first.
Table 6 shows the outputs for Data# Polling on DQ7.
Figure 5 shows the Data# Polling algorithm.
START
DQ7: Data# Polling
The Data# Polling bit, DQ7, indicates to the host
system whether an Embedded Algorithm is in progress
or completed, or whether the device is in Erase Suspend. Data# Polling is valid after the rising edge of the
final WE# pulse in the program or erase command
sequence.
During the Embedded Program algorithm, the device
outputs on DQ7 the complement of the datum programmed to DQ7. This DQ7 status also applies to
programming during Erase Suspend. When the
Embedded Program algorithm is complete, the device
outputs the datum programmed to DQ7. The system
must provide the program address to read valid status
information on DQ7. If a program address falls within a
protected sector, Data# Polling on DQ7 is active for
approximately 2 µs, then the device returns to reading
array data.
Read DQ7–DQ0
Addr = VA
DQ7 = Data?
No
No
DQ5 = 1?
Yes
During the Embedded Erase algorithm, Data# Polling
produces a “0” on DQ7. When the Embedded Erase
algorithm is complete, or if the device enters the Erase
Suspend mode, Data# Polling produces a “1” on DQ7.
This is analogous to the complement/true datum output
described for the Embedded Program algorithm: the
erase function changes all the bits in a sector to “1”;
prior to this, the device outputs the “complement,” or
“0.” The system must provide an address within any of
the sectors selected for erasure to read valid status
information on DQ7.
Read DQ7–DQ0
Addr = VA
After an erase command sequence is written, if all
sectors selected for erasing are protected, Data#
Polling on DQ7 is active for approximately 100 µs, then
the device returns to reading array data. If not all
selected sectors are protected, the Embedded Erase
algorithm erases the unprotected sectors, and ignores
the selected sectors that are protected.
FAIL
When the system detects DQ7 has changed from the
complement to true data, it can read valid data at DQ7–
DQ0 on the following read cycles. This is because DQ7
may change asynchronously with DQ0–DQ6 while
Output Enable (OE#) is asserted low. The Data#
Polling Timings (During Embedded Algorithms) figure
in the “AC Characteristics” section illustrates this.
Yes
DQ7 = Data?
Yes
No
PASS
Notes:
1. VA = Valid address for programming. During a sector
erase operation, a valid address is an address within any
sector selected for erasure. During chip erase, a valid
address is any non-protected sector address.
2. DQ7 should be rechecked even if DQ5 = “1” because
DQ7 may change simultaneously with DQ5.
Am29F004B
Figure 5.
Data# Polling Algorithm
19
DQ6: Toggle Bit I
Toggle Bit I on DQ6 indicates whether an Embedded
Program or Erase algorithm is in progress or complete,
or whether the device has entered the Erase Suspend
mode. Toggle Bit I may be read at any address, and is
valid after the rising edge of the final WE# pulse in the
command sequence (prior to the program or erase
operation), and during the sector erase time-out.
During an Embedded Program or Erase algorithm
operation, successive read cycles to any address
cause DQ6 to toggle. (The system may use either OE#
or CE# to control the read cycles.) When the operation
is complete, DQ6 stops toggling.
After an erase command sequence is written, if all
sectors selected for erasing are protected, DQ6 toggles
for approximately 100 µs, then returns to reading array
data. If not all selected sectors are protected, the
Embedded Erase algorithm erases the unprotected
sectors, and ignores the selected sectors that are
protected.
The system can use DQ6 and DQ2 together to determine whether a sector is actively erasing or is erasesuspended. When the device is actively erasing (that is,
the Embedded Erase algorithm is in progress), DQ6
toggles. When the device enters the Erase Suspend
mode, DQ6 stops toggling. However, the system must
also use DQ2 to determine which sectors are erasing
or erase-suspended. Alternatively, the system can use
DQ7 (see the subsection on DQ7: Data# Polling).
If a program address falls within a protected sector,
DQ6 toggles for approximately 2 µs after the program
command sequence is written, then returns to reading
array data.
DQ6 also toggles during the erase-suspend-program
mode, and stops toggling once the Embedded
Program algorithm is complete.
The Write Operation Status table shows the outputs for
Toggle Bit I on DQ6. Refer to Figure 6 for the toggle bit
algorithm, and to the Toggle Bit Timings figure in the
“AC Characteristics” section for the timing diagram.
The DQ2 vs. DQ6 figure shows the differences
between DQ2 and DQ6 in graphical form. See also the
subsection on DQ2: Toggle Bit II.
DQ2: Toggle Bit II
The “Toggle Bit II” on DQ2, when used with DQ6, indicates whether a particular sector is actively erasing
(that is, the Embedded Erase algorithm is in progress),
or whether that sector is erase-suspended. Toggle Bit
II is valid after the rising edge of the final WE# pulse in
the command sequence.
DQ2 toggles when the system reads at addresses
within those sectors that have been selected for era-
20
sure. (The system may use either OE# or CE# to
control the read cycles.) But DQ2 cannot distinguish
whether the sector is actively erasing or is erase-suspended. DQ6, by comparison, indicates whether the
device is actively erasing, or is in Erase Suspend, but
cannot distinguish which sectors are selected for erasure. Thus, both status bits are required for sector and
mode information. Refer to Table 6 to compare outputs
for DQ2 and DQ6.
Figure 6 shows the toggle bit algorithm in flowchart
form, and the section “DQ2: Toggle Bit II” explains the
algorithm. See also the DQ6: Toggle Bit I subsection.
Refer to the Toggle Bit Timings figure for the toggle bit
timing diagram. The DQ2 vs. DQ6 figure shows the differences between DQ2 and DQ6 in graphical form.
Reading Toggle Bits DQ6/DQ2
Refer to Figure 6 for the following discussion. Whenever the system initially begins reading toggle bit
status, it must read DQ7–DQ0 at least twice in a row to
determine whether a toggle bit is toggling. Typically, a
system would note and store the value of the toggle bit
after the first read. After the second read, the system
would compare the new value of the toggle bit with the
first. If the toggle bit is not toggling, the device has completed the program or erase operation. The system can
read array data on DQ7–DQ0 on the following read
cycle.
However, if after the initial two read cycles, the system
determines that the toggle bit is still toggling, the
system also should note whether the value of DQ5 is
high (see the section on DQ5). If it is, the system
should then determine again whether the toggle bit is
toggling, since the toggle bit may have stopped toggling just as DQ5 went high. If the toggle bit is no longer
toggling, the device has successfully completed the
program or erase operation. If it is still toggling, the
device did not complete the operation successfully, and
the system must write the reset command to return to
reading array data.
The remaining scenario is that the system initially
determines that the toggle bit is toggling and DQ5 has
not gone high. The system may continue to monitor the
toggle bit and DQ5 through successive read cycles,
determining the status as described in the previous
paragraph. Alternatively, it may choose to perform
other system tasks. In this case, the system must start
at the beginning of the algorithm when it returns to
determine the status of the operation (top of Figure 6).
DQ5: Exceeded Timing Limits
DQ5 indicates whether the program or erase time has
exceeded a specified internal pulse count limit. Under
these conditions DQ5 produces a “1.” This is a failure
condition that indicates the program or erase cycle was
not successfully completed.
Am29F004B
The DQ5 failure condition may appear if the system
tries to program a “1” to a location that is previously programmed to “0.” Only an erase operation can change
a “0” back to a “1.” Under this condition, the device
halts the operation, and when the operation has
exceeded the timing limits, DQ5 produces a “1.”
START
Under both these conditions, the system must issue the
reset command to return the device to reading array
data.
Read DQ7–DQ0
DQ3: Sector Erase Timer
Read DQ7–DQ0
(Note 1)
Toggle Bit
= Toggle?
No
After writing a sector erase command sequence, the
system may read DQ3 to determine whether or not an
erase operation has begun. (The sector erase timer
does not apply to the chip erase command.) If additional sectors are selected for erasure, the entire timeout also applies after each additional sector erase command. When the time-out is complete, DQ3 switches
from “0” to “1.” The system may ignore DQ3 if the
system can guarantee that the time between additional
sector erase commands will always be less than 50 µs.
See also the “Sector Erase Command Sequence”
section.
Yes
No
DQ5 = 1?
Yes
After the sector erase command sequence is written,
the system should read the status on DQ7 (Data#
Polling) or DQ6 (Toggle Bit I) to ensure the device has
accepted the command sequence, and then read DQ3.
If DQ3 is “1”, the internally controlled erase cycle has
begun; all further commands (other than Erase Suspend) are ignored until the erase operation is complete.
If DQ3 is “0”, the device will accept additional sector
erase commands. To ensure the command has been
accepted, the system software should check the status
of DQ3 prior to and following each subsequent sector
erase command. If DQ3 is high on the second status
check, the last command might not have been
accepted. Table 6 shows the outputs for DQ3.
Read DQ7–DQ0
Twice
Toggle Bit
= Toggle?
(Notes
1, 2)
No
Yes
Program/Erase
Operation Not
Complete, Write
Reset Command
Program/Erase
Operation Complete
Notes:
1. Read toggle bit twice to determine whether or not it is
toggling. See text.
2. Recheck toggle bit because it may stop toggling as DQ5
changes to “1”. See text.
Figure 6.
Am29F004B
Toggle Bit Algorithm
21
Table 6.
Operation
Standard
Mode
Erase
Suspend
Mode
Embedded Program Algorithm
Write Operation Status
DQ7
(Note 1)
DQ6
DQ5
(Note 2)
DQ3
DQ2
(Note 1)
DQ7#
Toggle
0
N/A
No toggle
Embedded Erase Algorithm
0
Toggle
0
1
Toggle
Reading within Erase
Suspended Sector
1
No toggle
0
N/A
Toggle
Reading within Non-Erase
Suspended Sector
Data
Data
Data
Data
Data
Erase-Suspend-Program
DQ7#
Toggle
0
N/A
N/A
Notes:
1. DQ7 and DQ2 require a valid address when reading status information. Refer to the appropriate subsection for further details.
2. DQ5 switches to ‘1’ when an Embedded Program or Embedded Erase operation has exceeded the maximum timing limits.
See “DQ5: Exceeded Timing Limits” for more information.
22
Am29F004B
ABSOLUTE MAXIMUM RATINGS
Storage Temperature
Plastic Packages . . . . . . . . . . . . . . . –65°C to +150°C
Ambient Temperature
with Power Applied. . . . . . . . . . . . . . –55°C to +125°C
Voltage with Respect to Ground
20 ns
20 ns
+0.8 V
–0.5 V
VCC (Note 1) . . . . . . . . . . . . . . . .–2.0 V to +7.0 V
A9, OE# (Note 2) . . . . . . . . . . . . –2.0 V to +12.5 V
–2.0 V
All other pins (Note 1) . . . . . . . . . –0.5 V to +7.0 V
20 ns
Output Short Circuit Current (Note 3) . . . . . . 200 mA
Figure 7. Maximum Negative
Overshoot Waveform
Notes:
1. Minimum DC voltage on input or I/O pins is –0.5 V. During
voltage transitions, input or I/O pins may overshoot VSS to
–2.0 V for periods of up to 20 ns. See Figure 7. Maximum
DC voltage on input or I/O pins is VCC +0.5 V. During
voltage transitions, input or I/O pins may overshoot to VCC
+2.0 V for periods up to 20 ns. See Figure 8.
2. Minimum DC input voltage on pins A9 and OE# is –0.5 V.
During voltage transitions, A9 and OE# may overshoot
VSS to –2.0 V for periods of up to 20 ns. See Figure 7.
Maximum DC input voltage on pin A9 is +12.5 V which
may overshoot to +13.5 V for periods up to 20 ns.
3. No more than one output may be shorted to ground at a
time. Duration of the short circuit should not be greater
than one second.
20 ns
VCC
+2.0 V
VCC
+0.5 V
2.0 V
Stresses above those listed under “Absolute Maximum
Ratings” may cause permanent damage to the device. This is
a stress rating only; functional operation of the device at
these or any other conditions above those indicated in the
operational sections of this data sheet is not implied.
Exposure of the device to absolute maximum rating
conditions for extended periods may affect device reliability.
20 ns
20 ns
Figure 8. Maximum Positive
Overshoot Waveform
OPERATING RANGES
Industrial (I) Devices
Ambient Temperature (TA) . . . . . . . . . –40°C to +85°C
Extended (E) Devices
Ambient Temperature (TA) . . . . . . . . –55°C to +125°C
VCC Supply Voltages
VCC for ± 5% devices . . . . . . . . . . .+4.75 V to +5.25 V
VCC for ± 10% devices . . . . . . . . . . . .+4.5 V to +5.5 V
Operating ranges define those limits between which the functionality of the device is guaranteed.
Am29F004B
23
DC CHARACTERISTICS
TTL/NMOS Compatible
Parameter
Description
Test Conditions
Typ
Max
Unit
±1.0
µA
50
µA
±1.0
µA
ILI
Input Load Current
VIN = VSS to VCC, VCC = VCC max
ILIT
A9, OE# Input Load Current
(Note 4)
VCC = VCC max;
A9, OE# = 12.5 V
ILO
Output Leakage Current
VOUT = VSS to VCC, VCC = VCC max
ICC1
VCC Active Read Current (Notes 1, 2)
CE# = VIL, OE# = VIH
20
30
mA
ICC2
VCC Active Write Current (Notes 1, 3, 4) CE# = VIL, OE# = VIH
30
40
mA
ICC3
VCC Standby Current (Note 1)
0.4
1
mA
VIL
Input Low Voltage
–0.5
0.8
V
VIH
Input High Voltage
2.0
VCC
+ 0.5
V
VID
Voltage for Autoselect and Temporary
Sector Unprotect
VCC = 5.0 V
11.5
12.5
V
VOL
Output Low Voltage
IOL = 12 mA, VCC = VCC min
0.45
V
VOH
Output High Voltage
IOH = –2.5 mA, VCC = VCC min
VLKO
Low VCC Lock-Out Voltage
CE#, OE# = VIH
2.4
3.2
Notes:
1. Maximum ICC specifications are tested with VCC = VCCmax.
2. The ICC current listed is typically less than 2 mA/MHz, with OE# at VIH.
3. ICC active while Embedded Erase or Embedded Program is in progress.
4. Not 100% tested.
24
Min
Am29F004B
V
4.2
V
DC CHARACTERISTICS
CMOS Compatible
Parameter
Description
Test Conditions
Min
Typ
Max
Unit
ILI
Input Load Current
VIN = VSS to VCC,
VCC = VCC max
±1.0
µA
ILIT
A9, OE#, Input Load Current
(Note 4)
VCC = VCC max;
A9, OE# = 12.5 V
50
µA
ILO
Output Leakage Current
VOUT = VSS to VCC,
VCC = VCC max
±1.0
µA
ICC1
VCC Active Read Current
(Notes 1, 2)
CE# = VIL, OE# = VIH
20
30
mA
ICC2
VCC Active Write Current
(Notes 1, 3, 4)
CE# = VIL, OE# = VIH
30
40
mA
ICC3
VCC Standby Current
(Notes 1, 5)
CE# = VCC ± 0.5 V
0.3
5
µA
VIL
Input Low Voltage
–0.5
0.8
V
VIH
Input High Voltage
0.7 x VCC
VCC + 0.3
V
VID
Voltage for Autoselect and
Temporary Sector Unprotect
VCC = 5.0 V
11.5
12.5
V
VOL
Output Low Voltage
IOL = 12 mA, VCC = VCC min
0.45
V
VOH1
Output High Voltage
VOH2
VLKO
IOH = –2.5 mA, VCC = VCC min
0.85 VCC
IOH = –100 µA, VCC = VCC min
VCC–0.4
Low VCC Lock-Out Voltage
3.2
V
4.2
V
Notes:
1. Maximum ICC specifications are tested with VCC = VCCmax.
2. The ICC current listed is typically less than 2 mA/MHz, with OE# at VIH.
3. ICC active while Embedded Erase or Embedded Program is in progress.
4. Not 100% tested.
5. ICC3 = 20 µA max at extended temperature (>+85° C).
Am29F004B
25
TEST CONDITIONS
Table 7.
Test Specifications
5.0 V
Test Condition
2.7 kΩ
Device
Under
Test
CL
All
others
-55
Output Load
Unit
1 TTL gate
Output Load Capacitance, CL
(including jig capacitance)
30
100
pF
Input Rise and Fall Times
5
20
ns
0.0–3.0
0.45–2.4
V
Input timing measurement
reference levels
1.5
0.8, 2.0
V
Output timing measurement
reference levels
1.5
0.8, 2.0
V
6.2 kΩ
Input Pulse Levels
Note: Diodes are IN3064 or equivalent
Figure 9.
Test Setup
KEY TO SWITCHING WAVEFORMS
WAVEFORM
INPUTS
OUTPUTS
Steady
Changing from H to L
Changing from L to H
26
Don’t Care, Any Change Permitted
Changing, State Unknown
Does Not Apply
Center Line is High Impedance State (High Z)
Am29F004B
AC CHARACTERISTICS
Read Operations
Parameter
Speed Options
JEDEC
Std
Description
tAVAV
tRC
Read Cycle Time (Note 1)
tAVQV
tACC
Address to Output Delay
tELQV
tCE
Chip Enable to Output Delay
tGLQV
tOE
tEHQZ
tGHQZ
tAXQX
Test Setup
-55
-70
-90
-120
Unit
Min
55
70
90
120
ns
CE# = VIL
OE# = VIL
Max
55
70
90
120
ns
OE# = VIL
Max
55
70
90
120
ns
Output Enable to Output Delay
Max
25
30
35
45
ns
tDF
Chip Enable to Output High Z (Note 1)
Max
15
20
20
30
ns
tDF
Output Enable to Output High Z
(Note 1)
Max
15
20
20
30
ns
Read
Min
0
ns
Toggle and
Data# Polling
Min
10
ns
Min
0
ns
tOEH
Output Enable
Hold Time
(Note 1)
tOH
Output Hold Time From Addresses, CE#
or OE#, Whichever Occurs First (Note 1)
Notes:
1. Not 100% tested.
2. See Table 7 and Figure 9 for test specifications.
tRC
Addresses Stable
Addresses
tACC
CE#
tDF
tOE
OE#
tOEH
WE#
tCE
tOH
HIGH Z
HIGH Z
Output Valid
Outputs
Figure 10.
Read Operations Timings
Am29F004B
27
AC CHARACTERISTICS
Erase/Program Operations
Parameter
Speed Options
JEDEC
Std
Description
-55
-70
-90
-120
Unit
tAVAV
tWC
Write Cycle Time (Note 1)
Min
55
70
90
120
ns
tAVWL
tAS
Address Setup Time
Min
tWLAX
tAH
Address Hold Time
Min
45
45
45
50
ns
tDVWH
tDS
Data Setup Time
Min
30
30
45
50
ns
tWHDX
tDH
Data Hold Time
Min
0
ns
tOES
Output Enable Setup Time
Min
0
ns
Read Recovery Time Before Write
(OE# High to WE# Low)
Min
0
ns
0
ns
tGHWL
tGHWL
tELWL
tCS
CE# Setup Time
Min
0
ns
tWHEH
tCH
CE# Hold Time
Min
0
ns
tWLWH
tWP
Write Pulse Width
Min
tWHWL
tWPH
Write Pulse Width High
Min
20
ns
tWHWH1
tWHWH1 Programming Operation (Note 2)
Typ
7
µs
tWHWH2
tWHWH2 Sector Erase Operation (Note 2)
Typ
1
sec
Min
50
µs
tVCS
VCC Setup Time (Note 1)
Notes:
1. Not 100% tested.
2. See the “Erase and Programming Performance” section for more information.
28
Am29F004B
35
35
45
50
ns
AC CHARACTERISTICS
Program Command Sequence (last two cycles)
tAS
tWC
Addresses
Read Status Data (last two cycles)
555h
PA
PA
PA
tAH
CE#
tCH
OE#
tWHWH1
tWP
WE#
tWPH
tCS
tDS
tDH
PD
A0h
Data
Status
DOUT
VCC
tVCS
Notes:
1. PA = program address, PD = program data, DOUT is the true data at the program address.
Figure 11.
Program Operation Timings
Erase Command Sequence (last two cycles)
tAS
tWC
Addresses
Read Status Data
2AAh
VA
SA
VA
555h for chip erase
tAH
CE#
tCH
OE#
tWP
WE#
tWPH
tCS
tWHWH2
tDS
tDH
Data
55h
30h
In
Progress
Complete
10 for Chip Erase
tVCS
VCC
Notes:
1. SA = sector address (for Sector Erase), VA = Valid Address for reading status data (”see “Write Operation Status”).
Figure 12.
Chip/Sector Erase Operation Timings
Am29F004B
29
AC CHARACTERISTICS
tRC
Addresses
VA
VA
VA
tACC
tCE
CE#
tCH
tOE
OE#
tOEH
tDF
WE#
tOH
High Z
DQ7
Complement
Complement
DQ0–DQ6
Status Data
Status Data
Valid Data
True
High Z
Valid Data
True
Note: VA = Valid address. Illustration shows first status cycle after command sequence, last status read cycle, and array data
read cycle.
Figure 13.
Data# Polling Timings (During Embedded Algorithms)
tRC
Addresses
VA
VA
VA
VA
tACC
tCE
CE#
tCH
tOE
OE#
tOEH
tDF
WE#
tOH
DQ6/DQ2
High Z
Valid Status
Valid Status
(first read)
(second read)
Valid Status
Valid Data
(stops toggling)
Note: VA = Valid address; not required for DQ6. Illustration shows first two status cycle after command sequence, last status read
cycle, and array data read cycle.
Figure 14.
Enter
Embedded
Erasing
WE#
Erase
Suspend
Erase
Toggle Bit Timings (During Embedded Algorithms)
Enter Erase
Suspend Program
Erase
Suspend
Program
Erase Suspend
Read
Erase
Resume
Erase Suspend
Read
Erase
Erase
Complete
DQ6
DQ2
Note: The system may use CE# or OE# to toggle DQ2 and DQ6. DQ2 toggles only when read at an address within an
erase-suspended sector.
Figure 15.
30
DQ2 vs. DQ6
Am29F004B
AC CHARACTERISTICS
Parameter
JEDEC
Std.
Description
tVIDR
VID Rise and Fall Time (Not 100% tested)
All Speed Options
Unit
500
ns
Min
VID
OE#
VSS, VIL
or VIH
tVIDR
A18 – A0
D7 – D0
555h
2AAh
555h
AAh
55h
20h/24h
CE#
WE#
Device is ready to read from array.
Figure 16.
If 20h is written, Sector Unprotect mode
is enabled. If 24h is written, command mode
Sector Protect/Unprotect is enabled.
Sector Unlock Sequence Timing Diagram
VID
OE# VSS, VIL
or VIH
0 V or 5 V
tVIDR
A18 – A0
D7 – D0
tVIDR
XXXh
XXXh
90h
F0h or 00h
CE#
WE#
Device is in either Temporary Sector Unprotect
mode or command mode Sector Protect/Unprotect.
Figure 17.
Device exits Temporary Sector Unprotect mode
or command mode Sector Protect/Unprotect.
Returns to reading array data.
Sector Relock Timing Diagram
Am29F004B
31
AC CHARACTERISTICS
VID
VIH
OE#
A18 – A0
D7 – D0
VSS
XXXh
Valid (Note 2)
Valid (Note 2)
60h
60h
40h
Array Data
CE#
WE#
Sector Unlock sequence (three cycles)
Sector Relock sequence (two cycles)
Notes:
1. To enable the command mode sector protection/unprotection algorithm, the system must issue the command 24h in the
sector unlock sequence.
2. For sector protection, a valid address consists of the sector address with A6 = 0, A5 = 1, A1 = 1, A0 = 0. For sector
unprotection, a valid address consists of the sector address with A6 = 1, A5 = 1, A1 = 1, A0 = 0.
Figure 18.
32
Sector Protect/Unprotect Timing Diagram
Am29F004B
AC CHARACTERISTICS
Alternate CE# Controlled Erase/Program Operations
Parameter
Speed Options
JEDEC
Std.
Description
-55
-70
-90
-120
Unit
tAVAV
tWC
Write Cycle Time (Note 1)
Min
55
70
90
120
ns
tAVEL
tAS
Address Setup Time
Min
tELAX
tAH
Address Hold Time
Min
45
45
45
50
ns
tDVEH
tDS
Data Setup Time
Min
30
30
45
50
ns
tEHDX
tDH
Data Hold Time
Min
0
ns
tOES
Output Enable Setup Time
Min
0
ns
tGHEL
tGHEL
Read Recovery Time Before Write
(OE# High to WE# Low)
Min
0
ns
tWLEL
tWS
WE# Setup Time
Min
0
ns
tEHWH
tWH
WE# Hold Time
Min
0
ns
tELEH
tCP
CE# Pulse Width
Min
tEHEL
tCPH
CE# Pulse Width High
Min
20
ns
tWHWH1
tWHWH1
Programming Operation (Note 2)
Typ
7
µs
tWHWH2
tWHWH2
Sector Erase Operation (Note 2)
Typ
1
sec
0
35
35
ns
45
50
ns
1. Not 100% tested.
2. See the “Erase and Programming Performance” section for more information.
Am29F004B
33
AC CHARACTERISTICS
555 for program
2AA for erase
PA for program
SA for sector erase
555 for chip erase
Data# Polling
Addresses
PA
tWC
tAS
tAH
tWH
WE#
tGHEL
OE#
tWHWH1 or 2
tCP
CE#
tWS
tCPH
tDS
tDH
DQ7#
Data
A0 for program
55 for erase
DOUT
PD for program
30 for sector erase
10 for chip erase
Notes:
1. PA = Program Address, PD = Program Data, DQ7# = complement of data written to device, DOUT = data written to device.
2. Figure indicates the last two bus cycles of the command sequence.
Figure 19.
34
Alternate CE# Controlled Write Operation Timings
Am29F004B
ERASE AND PROGRAMMING PERFORMANCE
Parameter
Typ (Note 1)
Max (Note 2)
Unit
Sector Erase Time
1
8
s
Chip Erase Time
8
Byte Programming Time
7
300
µs
3.6
10.8
s
Chip Programming Time (Note 3)
s
Comments
Excludes 00h programming
prior to erasure (Note 4)
Excludes system level
overhead (Note 5)
Notes:
1. Typical program and erase times assume the following conditions: 25°C, 5.0 V VCC, 1,000,000 cycles. Additionally,
programming typicals assume checkerboard pattern.
2. Under worst case conditions of 90°C, VCC = 4.5 V (4.75 V for ±5% devices), 1,000,000 cycles.
3. The typical chip programming time is considerably less than the maximum chip programming time listed, since most bytes
program faster than the maximum program times listed.
4. In the pre-programming step of the Embedded Erase algorithm, all bytes are programmed to 00h before erasure.
5. System-level overhead is the time required to execute the four-bus-cycle sequence for the program command. See Table 5
for further information on command definitions.
6. The device has a minimum guaranteed erase and program cycle endurance of 1,000,000 cycles.
LATCHUP CHARACTERISTICS
Description
Min
Max
Input voltage with respect to VSS on all pins except I/O pins
(including A9 and OE#)
–1.0 V
12.5 V
Input voltage with respect to VSS on all I/O pins
–1.0 V
VCC + 1.0 V
–100 mA
+100 mA
VCC Current
Note: Includes all pins except VCC. Test conditions: VCC = 5.0 V, one pin at a time.
PLCC PIN CAPACITANCE
Parameter
Symbol
Parameter Description
Test Conditions
Typ
Max
Unit
Input Capacitance
VIN = 0
4
6
pF
COUT
Output Capacitance
VOUT = 0
8
12
pF
CIN2
Control Pin Capacitance
VPP = 0
8
12
pF
CIN
Notes:
1. Sampled, not 100% tested.
2. Test conditions TA = 25°C, f = 1.0 MHz.
DATA RETENTION
Parameter
Test Conditions
Min
Unit
150°C
10
Years
125°C
20
Years
Minimum Pattern Data Retention Time
Am29F004B
35
PHYSICAL DIMENSIONS
PL 032—32-Pin Plastic Leaded Chip Carrier
Dwg rev AH; 10/99
36
Am29F004B
REVISION SUMMARY
Revision A (January 1999)
Revision B+3 (July 12, 1999)
Initial release.
Global
Revision B (March 10, 1999)
Deleted all references to the PDIP package. Changed
data sheet status to Preliminary.
Global
In-System Sector Protect/Unprotect Algorithms
figure
Revised document into full data sheet.
In-System Sector Protect/Sector Unprotect
Algorithms figure
Added tolerance specifications to the 150 µs and 15 ms
waits. Clarified that reading from the sector address
during either sector protect or unprotect algorithm
requires an access time of 1 µs.
Added requirements for asserting address A5 and
setting OE# to VIH during both algorithms.
Revision C (November 12, 1999)
Revision B+1 (March 18, 1999)
Command Definitions table
Added A5 requirement to definition for SA+ in the
legend. In the four th cycle of the Sector Relock
sequence, changed address from XXX to SA+.
Sector Protect/Unprotect Timing Diagram
Modified drawing to indicate that OE# should be
dropped to VIH during the third cycle.
AC Characteristics—Figure 11. Program
Operations Timing and Figure 12. Chip/Sector
Erase Operations
Deleted tGHWL and changed OE# waveform to start at
high.
Physical Dimensions
Replaced figures with more detailed illustrations.
Revision B+2 (May 14, 1999)
Revision D (February 22, 2000)
Ordering Information
Global
Changed the temperature range in the example to I.
The “preliminary” designation has been removed from
the document. Parameters are now stable, and only
speed, package, and temperature range combinations
are expected to change in future data sheet revisions.
Device Bus Operation table
Corrected the highest bit in the address range column
header to A18.
Command Definitions table
In Note 4, changed the address range for bits that are
don’t care to A18–A12.
Revision E (November 29, 2000)
Added table of contents.
Ordering Information
DC Characteristics table
Deleted burn-in option.
In Note 5, deleted reference to ICC4.
Table 5, Command Definitions
Read Operations Timings and Alternate CE#
Controlled Write Operations figures
In Note 4, corrected lower address bit of don’t care
range to A11.
Deleted RESET# waveform.
Trademarks
Copyright © 2000 Advanced Micro Devices, Inc. All rights reserved.
AMD, the AMD logo, and combinations thereof are registered trademarks of Advanced Micro Devices, Inc.
ExpressFlash is a trademark of Advanced Micro Devices, Inc.
Product names used in this publication are for identification purposes only and may be trademarks of their respective companies
Am29F004B
37