SN54F242, SN74F242

QUADRUPLE BUS TRANSCEIVERS

WITH 3STATE OUTPUTS

SDFS062A − D2932, MARCH 1987 − REVISED OCTOBER 1993

Copyright

2−1

POST OFFICE BOX 655303

POST OFFICE BOX 1443

Data Buses

Small-Outline Packages, Ceramic Chip

Carriers, and Standard Plastic and Ceramic

300-mil DIPs

description

These quadruple bus transceivers are designed

for asynchronous communications between data

buses. The control function implementation allows

for maximum flexibility in timing. These devices

allow data transmission from the A bus to the

B bus or from the B bus to the A bus depending

upon the logic levels at the output-enable (OEBA

and OEAB) inputs. The output-enable inputs can

be used to disable the device so that the buses are

effectively isolated.

The

dual-enable

configuration

gives

the

quadruple bus transceivers the capability to store

data by simultaneous enabling of OEBA and

OEAB. Each output reinforces its input in this

transceiver configuration. Thus, when both control

inputs are enabled and all other data sources to

the two sets of bus lines are at high impedance,

both sets of bus lines (eight in all) remain at their

states. The 4-bit codes appearing on the two sets

of buses will be complementary for the

′F242.

The SN54F242 is characterized for operation over the full military temperature range of − 55

°C to 125°C. The

SN74F242 is characterized for operation from 0

°C to 70°C.

FUNCTION TABLE

INPUTS

FUNCTION

OEAB

OEBA

FUNCTION

L

L

A to B

H

HB to A

H

L

Isolation

L

H

Latch A and B

(A = B)

SN54F242 ...J PACKAGE

SN74F242 ...D OR N PACKAGE

(TOP VIEW)

SN54F242 . . . FK PACKAGE

(TOP VIEW)

32

1 20 19

910 11 12 13

4

5

6

7

8

18

17

16

15

14

NC

NC

B1

NC

B2

A1

NC

A2

NC

A3

NC − No internal connection

1

2

3

4

5

6

7

14

13

12

11

10

9

8

OEAB

NC

A1

A2

A3

A4

GND

OEBA

NC

B1

B2

B3

B4

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.