ATMEL AT49F020

Features
• Single Voltage Operation
•
•
•
•
•
•
•
•
•
– 5V Read
– 5V Reprogramming
Fast Read Access Time - 55 ns
Internal Program Control and Timer
8K bytes Boot Block With Lockout
Fast Erase Cycle Time - 10 seconds
Byte By Byte Programming - 50 µs/Byte
Hardware Data Protection
DATA Polling For End Of Program Detection
Low Power Dissipation
– 50 mA Active Current
– 100 µA CMOS Standby Current
Typical 10,000 Write Cycles
Description
The AT49F020 is a 5-volt-only in-system Flash Memory. Its 2 megabits of memory is
organized as 262,144 words by 8 bits. Manufactured with Atmel’s advanced nonvolatile CMOS technology, the device offers access times to 55 ns with power dissipation
of just 275 mW over the commercial temperature range. When the device is deselected, the CMOS standby current is less than 100 µA.
To allow for simple in-system reprogrammability, the AT49F020 does not require high
input voltages for programming. Five-volt-only commands determine the read and
programming operation of the device. Reading data out of the device is similar to
reading from an EPROM. Reprogramming the AT49F020 is performed by erasing the
entire 2 megabits of memory and then programming on a byte by byte basis. The byte
programming time is a fast 50 µ s. The end of a program cycle can be optionally
detected by the DATA polling feature. Once the end of a byte program cycle has been
detected, a new access for a read or program can begin. The typical number of program and erase cycles is in excess of 10,000 cycles.
(continued)
Function
A0 - A17
Addresses
CE
Chip Enable
OE
Output Enable
WE
Write Enable
I/O0 - I/O7
Data Inputs/Outputs
NC
No Connect
AT49F020
DIP Top View
Pin Configurations
Pin Name
2-Megabit
(256K x 8)
5-volt Only
CMOS Flash
Memory
NC
A16
A15
A12
A7
A6
A5
A4
A3
A2
A1
A0
I/O0
I/O1
I/O2
GND
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
VCC
WE
A17
A14
A13
A8
A9
A11
OE
A10
CE
I/O7
I/O6
I/O5
I/O4
I/O3
TSOP Top View
Type 1
29
28
27
26
25
24
23
22
21
14
15
16
17
18
19
20
5
6
7
8
9
10
11
12
13
I/O1
I/O2
GND
I/O3
I/O4
I/O5
I/O6
A7
A6
A5
A4
A3
A2
A1
A0
I/O0
4
3
2
1
32
31
30
A12
A15
A16
NC
VCC
WE
A17
PLCC Top View
A14
A13
A8
A9
A11
OE
A10
CE
I/O7
A11
A9
A8
A13
A14
A17
WE
VCC
NC
A16
A15
A12
A7
A6
A5
A4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
OE
A10
CE
I/O7
I/O6
I/O5
I/O4
I/O3
GND
I/O2
I/O1
I/O0
A0
A1
A2
A3
0567B-A–8/97
1
The optional 8K bytes boot block section includes a reprogramming write lock out feature to provide data integrity.
The boot sector is designed to contain user secure code,
and when the feature is enabled, the boot sector is permanently protected from being reprogrammed.
Block Diagram
DATA INPUTS/OUTPUTS
I/O0 - I/O7
VCC
GND
OE
WE
CE
ADDRESS
INPUTS
OE, CE AND WE
LOGIC
DATA LATCH
INPUT/OUTPUT
BUFFERS
Y DECODER
Y-GATING
X DECODER
MAIN MEMORY
(248K BYTES)
OPTIONAL BOOT
BLOCK (8K BYTES)
Device Operation
READ: The AT49F020 is accessed like an EPROM. When
CE and OE are low and WE is high, the data stored at the
memory location determined by the address pins is
asserted on the outputs. The outputs are put in the high
impedance state whenever CE or OE is high. This dual-line
control gives designers flexibility in preventing bus contention.
ERASURE: Before a byte can be reprogrammed, the 256K
bytes memory array (or 248K bytes if the boot block featured is used) must be erased. The erased state of the
memory bits is a logical “1”. The entire device can be
erased at one time by using a 6-byte software code. The
software chip erase code consists of 6-byte load commands to specific address locations with a specific data
pattern (please refer to the Chip Erase Cycle Waveforms).
After the software chip erase has been initiated, the device
will internally time the erase operation so that no external
clocks are required. The maximum time needed to erase
the whole chip is tEC. If the boot block lockout feature has
been enabled, the data in the boot sector will not be
erased.
BYTE PROGRAMMING: Once the memory array is
erased, the device is programmed (to a logical “0”) on a
byte-by-byte basis. Please note that a data “0” cannot be
programmed back to a “1”; only erase operations can convert “0”s to “1”s. Programming is accomplished via the
internal device command register and is a 4 bus cycle operation (please refer to the Command Definitions table). The
device will automatically generate the required internal program pulses.
The program cycle has addresses latched on the falling
edge of WE or CE, whichever occurs last, and the data
latched on the rising edge of WE or CE, whichever occurs
first. Programming is completed after the specified tBP cycle
2
AT49F020
time. The DATA polling feature may also be used to indicate
the end of a program cycle.
BOOT BLOCK PROGRAMMING LOCKOUT: The device
has one designated block that has a programming lockout
feature. This feature prevents programming of data in the
designated block once the feature has been enabled. The
size of the block is 8K bytes. This block, referred to as the
boot block, can contain secure code that is used to bring up
the system. Enabling the lockout feature will allow the boot
code to stay in the device while data in the rest of the
device is updated. This feature does not have to be activated; the boot block's usage as a write protected region is
optional to the user. The address range of the boot block is
00000H to 01FFFH.
Once the feature is enabled, the data in the boot block can
no longer be erased or programmed. Data in the main
memory block can still be changed through the regular programming method. To activate the lockout feature, a series
of six program commands to specific addresses with specific data must be performed. Please refer to the Command
Definitions table.
BOOT BLOCK LOCKOUT DETECTION: A software
method is available to determine if programming of the boot
block section is locked out. When the device is in the software product identification mode (see Software Product
Identification Entry and Exit sections) a read from address
location 00002H will show if programming the boot block is
locked out. If the data on I/O0 is low, the boot block can be
programmed; if the data on I/O0 is high, the program lockout feature has been activated and the block cannot be
programmed. The software product identification code
should be used to return to standard operation.
AT49F020
PRODUCT IDENTIFICATION: The product identification
mode identifies the device and manufacturer as Atmel. It
may be accessed by hardware or software operation. The
hardware operation mode can be used by an external programmer to identify the correct programming algorithm for
the Atmel product.
For details, see Operating Modes (for hardware operation)
or Software Product Identification. The manufacturer and
device code is the same for both modes.
DATA POLLING: The AT49F020 features DATA polling to
indicate the end of a program cycle. During a program
cycle an attempted read of the last byte loaded will result in
the complement of the loaded data on I/O7. Once the program cycle has been completed, true data is valid on all
outputs and the next cycle may begin. DATA polling may
begin at any time during the program cycle.
TOGGLE BIT: In addition to DATA polling the AT49F020
provides another method for determining the end of a program or erase cycle. During a program or erase operation,
successive attempts to read data from the device will result
in I/O6 toggling between one and zero. Once the program
cycle has completed, I/O6 will stop toggling and valid data
will be read. Examining the toggle bit may begin at any time
during a program cycle.
HARDWARE DATA PROTECTION: Hardware features
protect against inadvertent programs to the AT49F020 in
the following ways: (a) VCC sense: if VCC is below 3.8V (typical), the program function is inhibited. (b) Program inhibit:
holding any one of OE low, CE high or WE high inhibits program cycles. (c) Noise filter: pulses of less than 15 ns (typical) on the WE or CE inputs will not initiate a program
cycle.
Command Definition (in Hex)
Command
Sequence
1st Bus
Cycle
Bus
Cycles
Addr
Data
Read
1
Addr
DOUT
Chip Erase
6
5555
Byte Program
4
Boot Block
Lockout (1)
Product ID
Entry
Product ID Exit
(2)
Product ID Exit
(2)
Notes:
2nd Bus
Cycle
3rd Bus
Cycle
4th Bus
Cycle
5th Bus
Cycle
6th Bus
Cycle
Addr
Data
Addr
Data
Addr
Data
Addr
Data
Addr
Data
AA
2AAA
55
5555
80
5555
AA
2AAA
55
5555
10
5555
AA
2AAA
55
5555
A0
Addr
DIN
6
5555
AA
2AAA
55
5555
80
5555
AA
2AAA
55
5555
40
3
5555
AA
2AAA
55
5555
90
3
5555
AA
2AAA
55
5555
F0
1
XXXX
F0
1.
The 8K byte boot sector has the address range 00000H to 01FFFH.
2.
Either one of the Product ID exit commands can be used.
Absolute Maximum Ratings*
Temperature Under Bias................................ -55°C to +125°C
Storage Temperature ..................................... -65°C to +150°C
All Input Voltages (including NC Pins)
with Respect to Ground ...................................-0.6V to +6.25V
All Output Voltages
with Respect to Ground .............................-0.6V to VCC + 0.6V
*NOTICE:
Stresses beyond those listed under “Absolute
Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and
functional operation of the device at these or any
other conditions beyond those indicated in the
operational sections of this specification is not
implied. Exposure to absolute maximum rating
conditions for extended periods may affect device
reliability.
Voltage on OE
with Respect to Ground ...................................-0.6V to +13.5V
3
DC and AC Operating Range
Operating
Temperature (Case)
Com.
Ind.
VCC Power Supply
AT49F020-55
AT49F020-70
AT49F020-90
0°C - 70°C
0°C - 70°C
0°C - 70°C
-40°C - 85°C
-40°C - 85°C
-40°C - 85°C
5V ± 10%
5V ± 10%
5V ± 10%
Operating Modes
Mode
CE
OE
WE
Ai
I/O
Read
VIL
VIL
VIH
Ai
DOUT
Program(2)
VIL
VIH
VIL
Ai
DIN
Standby/Write Inhibit
VIH
X(1)
X
X
High Z
Program Inhibit
X
X
VIH
Program Inhibit
X
VIL
X
Output Disable
X
VIH
X
High Z
Product Identification
Hardware
VIL
VIL
VIH
A1 - A17 = VIL, A9 = VH,(3)
A0 = VIL
Manufacturer Code(4)
A1 - A17 = VIL, A9 = VH,(3)
A0 = VIH
Device Code(4)
A0 = VIL, A1 - A17=VIL
Manufacturer Code(4)
A0 = VIH, A1 - A17=VIL
Device Code(4)
Software(5)
Notes:
1. X can be VIL or VIH.
2. Refer to AC Programming Waveforms.
3. VH = 12.0V ± 0.5V.
4. Manufacturer Code: 1FH, Device Code 0BH.
5. See details under Software Product Identification Entry/Exit.
DC Characteristics
Symbol
Parameter
Condition
ILI
Input Load Current
ILO
Max
Units
VIN = 0V to VCC
10
µA
Output Leakage Current
VI/O = 0V to VCC
10
µA
Com.
100
ISB1
VCC Standby Current CMOS
CE = VCC - 0.3V to VCC
µA
Ind.
300
µA
ISB2
VCC Standby Current TTL
CE = 2.0V to VCC
3
mA
VCC Active Current
f = 5 MHz; IOUT = 0 mA
50
mA
0.8
V
ICC
(1)
VIL
Input Low Voltage
VIH
Input High Voltage
VOL
Output Low Voltage
IOL = 2.1 mA
VOH1
Output High Voltage
IOH = -400 µA
2.4
V
VOH2
Output High Voltage CMOS
IOH = -100 µA; VCC = 4.5V
4.2
V
Note:
4
Min
In the erase mode, ICC is 90 mA.
AT49F020
2.0
V
.45
V
AT49F020
AC Read Characteristics
AT49F020-55
Symbol
Parameter
tACC
Address to Output Delay
55
CE to Output Delay
55
tCE
(1)
tOE(2)
tDF
(3)(4)
tOH
Min
Max
AT49F020-70
Min
AT49F020-90
Max
Min
Max
Units
70
90
ns
70
90
ns
OE to Output Delay
0
30
0
35
0
40
ns
CE or OE to Output Float
0
25
0
25
0
25
ns
Output Hold from OE, CE or
Address, whichever occurred first
0
0
0
ns
AC Read Waveforms(1)(2)(3)(4)
ADDRESS
ADDRESS VALID
CE
tCE
OE
tACC
HIGH Z
OUTPUT
Notes:
tDF
tOH
OUTPUT VALID
1. CE may be delayed up to tACC - tCE after the address transition without impact on tACC.
2. OE may be delayed up to tCE - tOE after the falling edge of CE without impact on tCE or by tACC - tOE after an address change
without impact on tACC.
3. tDF is specified from OE or CE whichever occurs first (CL = 5 pF).
4. This parameter is characterized and is not 100% tested.
Input Test Waveforms and Measurement Level
AC
DRIVING
LEVELS
3.0V
Output Test Load
AC
MEASUREMENT
LEVEL
1.5V
0.0V
5.0V
1.8K
OUTPUT
PIN
tR, tF < 5 ns
1.3K
100 pF
Pin Capacitance(1)
(f = 1 MHz, T = 25°C)
Typ
Max
Units
Conditions
CIN
4
6
pF
VIN = 0V
COUT
8
12
pF
VOUT = 0V
Note:
1. This parameter is characterized and is not 100% tested.
5
AC Byte Load Characteristics
Symbol
Parameter
Min
tAS, tOES
Address, OE Set-up Time
0
ns
tAH
Address Hold Time
50
ns
tCS
Chip Select Set-up Time
0
ns
tCH
Chip Select Hold Time
0
ns
tWP
Write Pulse Width (WE or CE)
90
ns
tDS
Data Set-up Time
50
ns
tDH, tOEH
Data, OE Hold Time
0
ns
tWPH
Write Pulse Width High
90
ns
AC Byte Load Waveforms
WE Controlled
OE
tOES
tOEH
ADDRESS
tAS
tAH
tCH
CE
tCS
WE
tWP
tDS
tWPH
tDH
DATA IN
CE Controlled
OE
tOES
tOEH
ADDRESS
tAS
tAH
tCH
WE
tCS
CE
tWP
tDS
DATA IN
6
AT49F020
tWPH
tDH
Max
Units
AT49F020
Program Cycle Characteristics
Symbol
Parameter
Min
Typ
Max
Units
tBP
Byte Programming Time
10
50
µs
tAS
Address Set-up Time
0
ns
tAH
Address Hold Time
50
ns
tDS
Data Set-up Time
50
ns
tDH
Data Hold Time
0
ns
tWP
Write Pulse Width
90
ns
tWPH
Write Pulse Width High
90
ns
tEC
Erase Cycle Time
10
seconds
Program Cycle Waveforms
PROGRAM CYCLE
OE
CE
tWP
tWPH
tBP
WE
tAS
tAH
5555
A0-A17
tDH
2AAA
5555
ADDRESS
tDS
AA
DATA
55
INPUT
DATA
A0
Chip Erase Cycle Waveforms
OE
CE
tWP
tWPH
WE
tAS
A0-A17
tAH
5555
tDH
2AAA
5555
5555
2AAA
5555
tDS
DATA
Note:
tEC
AA
55
80
AA
55
10
BYTE 0
BYTE 1
BYTE 2
BYTE 3
BYTE 4
BYTE 5
OE must be high only when WE and CE are both low.
7
Data Polling Characteristics (1)
Symbol
Parameter
Min
tDH
Data Hold Time
tOEH
OE Hold Time
Max
OE to Output Delay
tWR
Write Recovery Time
Units
10
ns
10
ns
(2)
tOE
Notes:
Typ
ns
0
ns
1. These parameters are characterized and not 100% tested.
2. See tOE spec in AC Read Characteristics
Data Polling Waveforms
WE
CE
tOEH
OE
tDH
tOE
tWR
I/O7
A0-A17
An
An
An
An
An
Toggle Bit Characteristics(1)
Symbol
Parameter
Min
tDH
Data Hold Time
tOEH
OE Hold Time
OE to Output Delay
tOEHP
OE High Pulse
tWR
Write Recovery Time
Max
Units
10
ns
10
ns
(2)
tOE
Notes:
Typ
ns
150
ns
0
ns
1. These parameters are characterized and not 100% tested.
2. See tOE spec in AC Read Characteristics.
Toggle Bit Waveforms(1)(2)(3)
WE
CE
tOEH
tOEHP
OE
tDH
I/O6
Notes:
8
tOE
tWR
HIGH Z
1.
Toggling either OE or CE or both OE and CE will operate toggle bit. The tOEHP specification must be met by the toggling
input(s).
2.
Beginning and ending state of I/O6 will vary.
3.
Any address location may be used but the address should not vary.
AT49F020
AT49F020
Software Product
Identification Entry(1)
Boot Block Lockout Feature
Enable Algorithm(1)
LOAD DATA AA
TO
ADDRESS 5555
LOAD DATA AA
TO
ADDRESS 5555
LOAD DATA 55
TO
ADDRESS 2AAA
LOAD DATA 55
TO
ADDRESS 2AAA
LOAD DATA 90
TO
ADDRESS 5555
LOAD DATA 80
TO
ADDRESS 5555
ENTER PRODUCT
IDENTIFICATION
MODE(2)(3)(5)
LOAD DATA AA
TO
ADDRESS 5555
LOAD DATA 55
TO
ADDRESS 2AAA
Software Product
Identification Exit(1)
LOAD DATA AA
TO
ADDRESS 5555
OR
LOAD DATA 55
TO
ADDRESS 2AAA
LOAD DATA AA
TO
ANY ADDRESS
LOAD DATA 40
TO
ADDRESS 5555
EXIT PRODUCT
IDENTIFICATION
MODE(4)
LOAD DATA F0
TO
ADDRESS 5555
PAUSE 1 second(2)
Notes:
1.
Data Format: I/O7 - I/O0 (Hex);
Address Format: A14 - A0 (Hex).
2.
Boot block lockout feature enabled.
EXIT PRODUCT
IDENTIFICATION
MODE(4)
Notes:
1.
Data Format: I/O7 - I/O0 (Hex);
Address Format: A14 - A0 (Hex).
2.
A1 - A17 = VIL.
Manufacture Code is read for A0 = VIL;
Device Code is read for A0 = VIH.
3.
The device does not remain in identification mode if
powered down.
4.
The device returns to standard operation mode.
5.
Manufacturers Code: 1FH
Device Code: 0BH.
9
Ordering Information (1)
ICC (mA)
tACC
(ns)
Active
Standby
Ordering Code
Package
55
50
0.1
AT49F020-55JC
32J
Commercial
AT49F020-55PC
32P6
(0° to 70°C)
AT49F020-55TC
32T
AT49F020-55JI
32J
AT49F020-55PI
32P6
AT49F020-55TI
32T
AT49F020-70JC
32J
Commercial
AT49F020-70PC
32P6
(0° to 70°C)
AT49F020-70TC
32T
50
70
50
50
90
50
50
Note:
0.3
0.1
0.3
0.1
0.3
Industrial
(-40° to 85°C)
AT49F020-70JI
32J
AT49F020-70PI
32P6
AT49F020-70TI
32T
AT49F020-90JC
32J
Commercial
AT49F020-90PC
32P6
(0° to 70°C)
AT49F020-90TC
32T
AT49F020-90JI
32J
AT49F020-90PI
32P6
AT49F020-90TI
32T
Industrial
(-40° to 85°C)
Industrial
(-40° to 85°C)
The AT49F020 has as optional boot block feature. The part number shown in the Ordering Information table is for devices with
the boot block in the lower address range (i.e., 00000H to 01FFFH). Users requiring the boot block to be in the higher address
range should contact Atmel.
Package Type
32J
32 Lead, Plastic, J-Leaded Chip Carrier Package (PLCC)
32P6
32 Lead, 0.600" Wide, Plastic Dual Inline Package (PDIP)
32T
32 Lead, Thin Small Outline Package (TSOP)
10
Operation Range
AT49F020