DS1225Y

64K Nonvolatile SRAM

DS1225Y

021998 1/8

FEATURES

external power

PROM

+85

°C, designated IND

PIN ASSIGNMENT

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

NC

A12

A7

A6

A5

A4

A3

A2

A1

A0

DQ0

DQ1

DQ2

GND

VCC

NC

A8

A9

A11

A10

DQ7

DQ6

DQ5

DQ4

DQ3

WE

OE

CE

28–PIN ENCAPSULATED PACKAGE

720 MIL EXTENDED

PIN DESCRIPTION

A0–A12

– Address Inputs

DQ0–DQ7

– Data In/Data Out

CE

– Chip Enable

WE

– Write Enable

OE

– Output Enable

– Power (+5V)

GND

– Ground

NC

– No Connect

DESCRIPTION

The DS1225Y 64K Nonvolatile SRAM is a 65,536–bit,

fully static, nonvolatile RAM organized as 8192 words

by 8 bits. Each NV SRAM has a self–contained lithium

energy source and control circuitry which constantly

such a condition occurs, the lithium energy source is

automatically switched on and write protection is uncon-

ditionally enabled to prevent data corruption. The NV

SRAM can be used in place of existing 8K x 8 SRAMs

directly conforming to the popular bytewide 28–pin DIP

standard. The DS1225Y also matches the pinout of the

2764 EPROM or the 2864 EEPROM, allowing direct

substitution while enhancing performance. There is no

limit on the number of write cycles that can be executed

and no additional support circuitry is required for micro-

processor interfacing.