ATMEL AT27C020-70TC, AT27C020-70PI, AT27C020-70PC, AT27C020-70JI, AT27C020-70JC Datasheet

Features

• Fast Read Access Time - 55 ns

• Low Power CMOS Operation

– 100 µA max. Standby
– 25 mA max. Active at 5 MHz

• JEDEC Standard Packages

– 32-Lead 600-mil PDIP
– 32-Lead PLCC
– 32-Lead TSOP

• 5V ± 10% Supply

• High-Reliability CMOS Technology

– 2,000V ESD Protection
– 200 mA Latchup Immunity

™

• Rapid

• CMOS and TTL Compatible Inputs and Outputs

• Integrated Product Identification Code

• Commercial and Industrial Temperature Ranges

Programming Algorithm - 100 µs/byte (typical)

AT27C020

2-Megabit
(256K x 8)
OTP EPROM

Description

The AT27C020 is a low-power, high performance 2,097,152-bit one-time programma­ble read only memory (OTP EPROM) organized as 256K by 8 bits. It requires only
one 5V power su pply in normal re ad mode o peration. Any by te can b e acces sed in
less than 55 ns, elimi nating th e need for speed redu cing WA IT states on high perfo r­mance microprocessor systems.

In read mode, the AT27C020 typ ical ly con su mes 8 mA . Stan dby mode supply current

µ

is typically less than 10

Pin Configurations

Pin Name Function

A0 - A17 Addresses
O0 - O7 Outputs
CE
OE
PGM

VPP

A16
A15
A12

A7
A6
A5
A4
A3
A2
A1

A0
O0
O1
O2

GND

Chip Enable
Output Enable
Program Strobe

PDIP Top View

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16

A.

PLCC Top View

A12

A15

A16

VPP

VCC

PGM

A17

432

1

323130

29

A14

28

A13

27

A8

26

A9

25

A11

24

OE

23

A10

22

CE

21

07

02

030405

GND

06

O0

5

A7

6

A6

7

A5

8

A4

9

A3

10

A2

11

A1

12

A0

13

14151617181920

01

TSOP Top Vi ew

Type 1

32

VCC

31

PGM

30

A17

29

A14

28

A13

27

A8

26

A9

25

A11

24

OE

23

A10

22

CE

21

07

20

06

19

05

18

04
03

17

A11

A13
A14
A17

PGM

VCC

VPP

A16
A15
A12

1
2

A9

3

A8

4
5
6
7
8
9
10
11
12
13

A7

14

A6

15

A5

16

A4

OE

32

A10

31

CE

30

07

29

06

28

05

27

04

26

03

25

GND

24

02

23

01

22

O0

21

A0

20

A1

19

A2

18

A3

17

AT27C020

Rev. 0570C-B–12/97

1

The AT27C020 is available in a choice of industry standard
JEDEC-approved one -time program mable (OTP) plasti c
PDIP, PLCC, and TSOP packages. All devices feature two­line control (CE
vent bus contention.

With 256K byte storage capability, the AT27C020 allows
firmware to be stored reliably and to be accessed by the
system without the delays of mass storage media.

Atmel’s 27C020 have additional features to ensure high
quality and efficient production use. The Rapid
ming Algorithm reduces the time required to program the
part and guarantees reliable programming. Programming
time is typically only 100 µs/byte. The Integrated Product
Identification Code electronic ally identi fies the devic e and
manufacturer. This feature is used by industry standard
programmin g equip ment to se lect th e prope r prog rammi ng
algorithms and voltages.

, OE) to give desig ners the f lexib ility to pre-

™

Program-

Block Diagram

System Considerations

Switching between active and standby conditions via the
Chip Enable pin may prod uce tr ans ie nt v olt age excur sions.
Unless accommodated by the system design, these tran­sients may exceed data sheet limits, resulting in device
non-conformance. At a minimum, a 0.1 µF high frequ enc y,
low inherent inductance, ceramic capacitor should be uti­lized for each device. This capacitor shoul d be connected
between the V
close to the device as possible. Additionally, to stabilize the
supply voltage level on printed circuit boards with large
EPROM arrays, a 4.7 µF bulk electrolytic capacitor should
be utilized, again connected between the V
terminals. This capacitor should be positioned as close as
possible to the point where the power supply is connected
to the array.

and Ground terminals of the device, as

CC

and Ground

CC

2

AT27C020

Absolute Maximum Ratings*

AT27C020

Temperature Under Bias.......................-55°C to +125°C

*NOTICE: Stresses beyond those listed under “Absolute

Maximum Ratings” may cause permanent

Storage Temperature............................-65°C to +150°C

damage to the device. This is a stress rating
only and functional operation of the device at

Voltage on Any Pin with

Respect to Ground ...............................-2.0V to +7.0V

Voltage on A9 with

Respect to Ground ............................-2.0V to +14.0V

(1)

(1)

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.

Note: 1. Minimum vo lta ge is -0.6V DC which may

VPP Supply Voltage with

Respect to Ground .............................-2.0V to +14.0V

(1)

undershoot to -2.0V for pulses of less than 20
ns. Maximum output pin voltage is V

0.75V DC which may overshoot to +7.0V for
pulses of less than 20 ns.

Operating Modes

Mode/Pin CE OE PGM Ai V

Read V

IL

Output Disable X V
Standby V
Rapid Program

(2)

PGM Verify V
PGM Inhibit V

Product Identification

Notes: 1. X can be VIL or V

2. Refer to Programming Characteristics.

3. VH = 12.0 ± 0.5V.

4. Two identifier bytes may be selected. All Ai inputs are held low (VIL), except A9 which is set to VH and A0 which is toggled
low (V

(4)

IH.

) to select the Manufacturer’s Identification byte and high (VIH) to select the Device Code byte.

IL

IH

V

IL

IL

IH

V

IL

V

IL

IH

XXXXHigh Z

V

IH

V

IL

XX X V

V

IL

(1)

X

Ai X D

XXXHigh Z

V

IL

V

IH

X

Ai V
Ai V

A9 = V

(3)

H

A0 = VIH or V
A1 - A17 = V

IL
IL

+

CC

PP

PP

PP

PP

Outputs

OUT

D

IN

D

OUT

High Z

X Identification Code

3