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AT49F020 Datasheet, PDF (1/10 Pages) ATMEL Corporation – 2-Megabit 256K x 8 5-volt Only CMOS Flash Memory
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 nonvola-
tile 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 dese-
lected, 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 µs. 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 pro-
gram and erase cycles is in excess of 10,000 cycles.
(continued)
Pin Configurations
Pin Name Function
A0 - A17
Addresses
CE
Chip Enable
OE
Output Enable
WE
Write Enable
I/O0 - I/O7 Data Inputs/Outputs
DIP Top View
NC 1
A16 2
A15 3
A12 4
A7 5
A6 6
A5 7
A4 8
A3 9
A2 10
A1 11
A0 12
I/O0 13
I/O1 14
I/O2 15
GND 16
32 VCC
31 WE
30 A17
29 A14
28 A13
27 A8
26 A9
25 A11
24 OE
23 A10
22 CE
21 I/O7
20 I/O6
19 I/O5
18 I/O4
17 I/O3
NC
No Connect
PLCC Top View
A7 5
A6 6
A5 7
A4 8
A3 9
A2 10
A1 11
A0 12
I/O0 13
29 A14
28 A13
27 A8
26 A9
25 A11
24 OE
23 A10
22 CE
21 I/O7
TSOP Top View
Type 1
A11 1
A9 2
A8 3
A13 4
A14 5
A17 6
WE 7
VCC 8
NC 9
A16 10
A15 11
A12 12
A7 13
A6 14
A5 15
A4 16
32 OE
31 A10
30 CE
29 I/O7
28 I/O6
27 I/O5
26 I/O4
25 I/O3
24 GND
23 I/O2
22 I/O1
21 I/O0
20 A0
19 A1
18 A2
17 A3
2-Megabit
(256K x 8)
5-volt Only
CMOS Flash
Memory
AT49F020
0567B-A–8/97
1