SN54HC259, SN74HC259

8-BIT ADDRESSABLE LATCHES

SCLS134B – DECEMBER 1982 – REVISED MAY 1997

1

POST OFFICE BOX 655303

Performs Serial-to-Parallel Conversion With

Storage

Small-Outline (D), Thin Shrink

Small-Outline (PW), and Ceramic Flat (W)

Packages, Ceramic Chip Carriers (FK), and

Standard Plastic (N) and Ceramic (J)

300-mil DIPs

description

These 8-bit addressable latches are designed for

general-purpose storage applications in digital

systems. Specific uses include working registers,

serial-holding registers, and active-high decoders

or

demultiplexers.

They

are

multifunctional

devices capable of storing single-line data in eight

addressable latches, and being a 1-of-8 decoder

or demultiplexer with active-high outputs.

Four distinct modes of operation are selectable by

controlling the clear (CLR) and enable (G) inputs.

In the addressable-latch mode, data at the data-in

terminal is written into the addressed latch. The

addressed latch follows the data input with all

unaddressed latches remaining in their previous

states. In the memory mode, all latches remain in

their previous states and are unaffected by the

data or address inputs. To eliminate the possibility

of entering erroneous data in the latches, G

should be held high (inactive) while the address

lines are changing. In the 1-of-8 decoding or

demultiplexing mode, the addressed output

follows the level of the D input with all other

outputs low. In the clear mode, all outputs are low

and unaffected by the address and data inputs.

The SN54HC259 is characterized for operation over the full military temperature range of –55

°C to 125°C. The

SN74HC259 is characterized for operation from –40

°C to 85°C.

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

SN54HC259 ...J OR W PACKAGE

SN74HC259 . . . D, N, OR PW PACKAGE

(TOP VIEW)

32

1 20 19

910 11 12 13

4

5

6

7

8

18

17

16

15

14

G

D

NC

Q7

Q6

S2

Q0

NC

Q1

Q2

SN54HC259 . . . FK PACKAGE

(TOP VIEW)

1

2

3

4

5

6

7

8

16

15

14

13

12

11

10

9

S0

S1

S2

Q0

Q1

Q2

Q3

GND

CLR

G

D

Q7

Q6

Q5

Q4

NC – No internal connection

Copyright

© 1997, Texas Instruments Incorporated

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of Texas Instruments

standard warranty. Production processing does not necessarily include

testing of all parameters.