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033004

FEATURES

10 years minimum data retention in the

absence of external power

Data is automatically protected during power

loss

Unlimited write cycles

Low-power CMOS operation

Read and write access times as fast as 70 ns

Lithium energy source is electrically

disconnected to retain freshness until power is

applied for the first time

Full

±=10% V

Optional

±=5% V

(DS1249AB)

Optional industrial temperature range of

-40

°C to +85°C, designated IND

JEDEC standard 32-pin DIP package

PIN ASSIGNMENT

PIN DESCRIPTION

A0 - A17

- 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 DS1249 2048k Nonvolatile SRAMs are 2,097,152-bit, fully static, nonvolatile SRAMs organized as

262,144 words by 8 bits. Each NV SRAM has a self-contained lithium energy source and control circuitry

lithium energy source is automatically switched on and write protection is unconditionally enabled to

prevent data corruption. There is no limit on the number of write cycles which can be executed and no

additional support circuitry is required for microprocessor interfacing.

DS1249Y/AB

2048k Nonvolatile SRAM

www.maxim-ic.com

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31

32-Pin ENCAPSULATED PACKAGE

740-mil EXTENDED

A14

A7

A5

A4

A3

A2

A1

A0

DQ1

DQ0

A15

A17

WE

A13

A8

A9

A11

OE

A10

CE

DQ7

DQ5

DQ6

32

30

29

28

27

26

25

24

23

22

21

19

20

A16

A12

A6

NC

DQ2

GND

15

16

18

17

DQ4

DQ3