 2004 Microchip Technology Inc.

DS11001N-page 1

27C256

FEATURES

• High speed performance

- 90 ns access time available

• CMOS Technology for low power consumption

- 20 mA Active current

- 100

µA Standby current

• Factory programming available

• Auto-insertion-compatible plastic packages

• Auto ID aids automated programming

• Separate chip enable and output enable controls

• High speed “express” programming algorithm

• Organized 32K x 8: JEDEC standard pinouts

- 28-pin Dual-in-line package

- 32-pin PLCC Package

- 28-pin SOIC package

- Tape and reel

• Data Retention > 200 years

• Available for the following temperature ranges:

- Commercial:

0°C to +70°C

- Industrial:

-40°C to +85°C

- Automotive:

-40°C to +125°C

DESCRIPTION

The Microchip Technology Inc. 27C256 is a CMOS

256K bit electrically Programmable Read Only Memory

(EPROM). The device is organized as 32K words by 8

bits (32K bytes). Accessing individual bytes from an

address transition or from power-up (chip enable pin

going low) is accomplished in less than 90 ns. This very

high speed device allows the most sophisticated micro-

processors to run at full speed without the need for

WAIT states. CMOS design and processing enables

this part to be used in systems where reduced power

consumption and reliability are requirements.

A complete family of packages is offered to provide the

most flexibility in applications. For surface mount appli-

cations, PLCC, or SOIC packaging is available. Tape

and reel packaging is also available for PLCC or SOIC

packages.

PACKAGE TYPES

1

2

3

4

5

6

7

8

9

10

11

12

13

14

28

27

26

25

24

23

22

21

20

19

18

17

16

15

A12

A7

A6

A5

A4

A3

A2

A1

A0

O0

O1

O2

A14

A13

A8

A9

A11

OE

A10

CE

O7

O6

O5

O4

O3

A6

A5

A4

A3

A2

A1

A0

NC

O0

A8

A9

A11

NC

OE

A10

CE

O7

O6

5

6

7

8

9

10

11

12

13

29

28

27

26

25

24

23

22

21

PLCC

DIP/SOIC

256K (32K x 8) CMOS EPROM

Obsolete Device