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REV: 011204

Note: Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of any device

may be simultaneously available through various sales channels. For information about device errata, click here: www.maxim-ic.com/errata.

FEATURES

§ Integrated NV SRAM, Real-Time Clock,

Crystal, Power-Fail Control Circuit, and

Lithium Energy Source

§ Clock Registers are Accessed Identically to

the Static RAM. These Registers are Resident

in the Eight Top RAM Locations.

§ Century Byte Register (i.e., Y2K Compliant)

§ Totally Nonvolatile with Over 10 Years of

Operation in the Absence of Power

§ BCD-Coded Century, Year, Month, Date,

Day, Hours, Minutes, and Seconds with

Automatic Leap-Year Compensation Valid

Up to the Year 2100

§ Battery Voltage-Level Indicator Flag

§ Power-Fail Write Protection Allows for ±10%

§ Lithium Energy Source is Electrically

Disconnected to Retain Freshness Until

Power is Applied for the First Time

§ DIP Module Only

Standard JEDEC Byte-Wide 32k x 8 Static

RAM Pinout

Surface-Mountable Package for Direct

Connection to PowerCap Containing

Battery and Crystal

Replaceable Battery (PowerCap)

Power-On Reset Output

Pin-for-Pin Compatible with Other Densities

of DS174xP Timekeeping RAM

§ Also Available in Industrial Temperature

Range: -40°C to +85°C

PIN CONFIGURATIONS

PowerCap is a registered trademark of Dallas Semiconductor.

DS1744/DS1744P

Y2K-Compliant, Nonvolatile Timekeeping RAMs

www.maxim-ic.com

PDIP Module

(700-mil Extended)

WE

A13

A8

A9

A11

OE

A10

CE

DQ7

DQ6

DQ5

DQ4

DQ3

1

2

3

4

5

6

7

8

9

10

11

12

13

14

A14

A12

A7

A6

A5

A4

A3

A2

A1

A0

DQ0

DQ1

DQ2

GND

28

27

26

25

24

23

22

21

20

19

18

17

16

15

Dallas

Semiconductor

DS1744

1

N.C.

2

3

N.C.

N.C.

RST

WE

OE

CE

DQ7

DQ6

DQ5

DQ4

DQ3

DQ2

DQ1

DQ0

GND

4

5

6

7

8

9

10

11

12

13

14

15

16

17

N.C.

A14

33

32

31

30

29

28

27

26

25

24

23

22

21

20

19

18

A13

A12

A11

A10

A9

A8

A7

A6

A5

A4

A3

A2

A1

A0

34

N.C.

X1

GND

X2

PowerCap Module Board

(Uses DS9034PCX PowerCap)

Dallas

Semiconductor

DS1744P

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